Merge branch 'outputRefactoring' into next

58 files changed, 2953 insertions, 2531 deletions

diff --git a/src/BlockPartitioner.cpp b/src/BlockPartitioner.cpp
index 9e9f80b..5767650 100644
--- a/src/BlockPartitioner.cpp
+++ b/src/BlockPartitioner.cpp
@@ -1,6 +1,11 @@
 /*
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
  */
 /*
    This file is part of ODR-DabMod.
@@ -21,6 +26,7 @@
 
 #include "BlockPartitioner.h"
 #include "PcDebug.h"
+#include "Log.h"
 
 #include <stdio.h>
 #include <stdexcept>
@@ -31,6 +37,7 @@
 
 BlockPartitioner::BlockPartitioner(unsigned mode, unsigned phase) :
     ModMux(),
+    ModMetadata(),
     d_mode(mode)
 {
     PDEBUG("BlockPartitioner::BlockPartitioner(%i)\n", mode);
@@ -68,17 +75,11 @@ BlockPartitioner::BlockPartitioner(unsigned mode, unsigned phase) :
     d_cifNb = 0;
     // For Synchronisation purpose, count nb of CIF to drop
     d_cifPhase = phase % d_cifCount;
+    d_metaPhase = phase % d_cifCount;
     d_cifSize = 864 * 8;
 }
 
 
-BlockPartitioner::~BlockPartitioner()
-{
-    PDEBUG("BlockPartitioner::~BlockPartitioner()\n");
-
-}
-
-
 // dataIn[0] -> FIC
 // dataIn[1] -> CIF
 int BlockPartitioner::process(std::vector<Buffer*> dataIn, Buffer* dataOut)
@@ -124,10 +125,10 @@ int BlockPartitioner::process(std::vector<Buffer*> dataIn, Buffer* dataOut)
     uint8_t* out = reinterpret_cast<uint8_t*>(dataOut->getData());
 
     // Copy FIC data
-    PDEBUG("Writting FIC %zu bytes to %zu\n", d_ficSize, d_cifNb * d_ficSize);
+    PDEBUG("Writing FIC %zu bytes to %zu\n", d_ficSize, d_cifNb * d_ficSize);
     memcpy(out + (d_cifNb * d_ficSize), fic, d_ficSize);
     // Copy CIF data
-    PDEBUG("Writting CIF %u bytes to %zu\n", 864 * 8,
+    PDEBUG("Writing CIF %u bytes to %zu\n", 864 * 8,
             (d_cifCount * d_ficSize) + (d_cifNb * 864 * 8));
     memcpy(out + (d_cifCount * d_ficSize) + (d_cifNb * 864 * 8), cif, 864 * 8);
 
@@ -137,3 +138,28 @@ int BlockPartitioner::process(std::vector<Buffer*> dataIn, Buffer* dataOut)
 
     return d_cifNb == 0;
 }
+
+meta_vec_t BlockPartitioner::process_metadata(const meta_vec_t& metadataIn)
+{
+    // Synchronize CIF phase
+    if (d_metaPhase != 0) {
+        if (++d_metaPhase == d_cifCount) {
+            d_metaPhase = 0;
+        }
+        // Drop this metadata
+        return {};
+    }
+
+    if (d_cifNb == 1) {
+        d_meta.clear();
+    }
+
+    std::copy(metadataIn.begin(), metadataIn.end(), std::back_inserter(d_meta));
+
+    if (d_cifNb == 0) {
+        return d_meta;
+    }
+    else {
+        return {};
+    }
+}
diff --git a/src/BlockPartitioner.h b/src/BlockPartitioner.h
index 90cffa3..a4656a1 100644
--- a/src/BlockPartitioner.h
+++ b/src/BlockPartitioner.h
@@ -1,6 +1,11 @@
 /*
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
  */
 /*
    This file is part of ODR-DabMod.
@@ -25,32 +30,32 @@
 #   include <config.h>
 #endif
 
-
 #include "ModPlugin.h"
 #include <vector>
+#include <cstddef>
 
-#include <sys/types.h>
-
-
-class BlockPartitioner : public ModMux
+class BlockPartitioner : public ModMux, public ModMetadata
 {
 public:
     BlockPartitioner(unsigned mode, unsigned phase);
-    virtual ~BlockPartitioner();
-    BlockPartitioner(const BlockPartitioner&);
-    BlockPartitioner& operator=(const BlockPartitioner&);
 
     int process(std::vector<Buffer*> dataIn, Buffer* dataOut);
     const char* name() { return "BlockPartitioner"; }
 
+    // The implementation assumes process_metadata is always called after process
+    virtual meta_vec_t process_metadata(const meta_vec_t& metadataIn);
+
 protected:
     int d_mode;
     size_t d_ficSize;
     size_t d_cifCount;
     size_t d_cifNb;
     size_t d_cifPhase;
+    size_t d_metaPhase;
     size_t d_cifSize;
     size_t d_outputFramesize;
     size_t d_outputFramecount;
+
+    meta_vec_t d_meta;
 };
 
diff --git a/src/ConfigParser.cpp b/src/ConfigParser.cpp
index 2c93a57..7603c1e 100644
--- a/src/ConfigParser.cpp
+++ b/src/ConfigParser.cpp
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -29,15 +29,17 @@
 #   include "config.h"
 #endif
 
+#include <cstdint>
+#include <boost/property_tree/ptree.hpp>
+#include <boost/property_tree/ini_parser.hpp>
+
 #include "ConfigParser.h"
 #include "porting.h"
 #include "Utils.h"
 #include "Log.h"
 #include "DabModulator.h"
+#include "output/SDR.h"
 
-#include <unistd.h>
-#include <boost/property_tree/ptree.hpp>
-#include <boost/property_tree/ini_parser.hpp>
 
 using namespace std;
 
@@ -202,87 +204,101 @@ static void parse_configfile(
     if (output_selected == "file") {
         try {
             mod_settings.outputName = pt.get<std::string>("fileoutput.filename");
+            mod_settings.fileOutputShowMetadata =
+                (pt.get("fileoutput.show_metadata", 0) > 0);
         }
         catch (std::exception &e) {
             std::cerr << "Error: " << e.what() << "\n";
             std::cerr << "       Configuration does not specify file name for file output\n";
             throw std::runtime_error("Configuration error");
         }
-        mod_settings.useFileOutput = 1;
+        mod_settings.useFileOutput = true;
 
         mod_settings.fileOutputFormat = pt.get("fileoutput.format", mod_settings.fileOutputFormat);
     }
 #if defined(HAVE_OUTPUT_UHD)
     else if (output_selected == "uhd") {
-        OutputUHDConfig outputuhd_conf;
+        Output::SDRDeviceConfig sdr_device_config;
 
-        outputuhd_conf.device = pt.get("uhdoutput.device", "");
-        outputuhd_conf.usrpType = pt.get("uhdoutput.type", "");
-        outputuhd_conf.subDevice = pt.get("uhdoutput.subdevice", "");
-        outputuhd_conf.masterClockRate = pt.get<long>("uhdoutput.master_clock_rate", 0);
+        string device = pt.get("uhdoutput.device", "");
+        const auto usrpType = pt.get("uhdoutput.type", "");
+        if (usrpType != "") {
+            if (not device.empty()) {
+                device += ",";
+            }
+            device += "type=" + usrpType;
+        }
+        sdr_device_config.device = device;
+
+        sdr_device_config.subDevice = pt.get("uhdoutput.subdevice", "");
+        sdr_device_config.masterClockRate = pt.get<long>("uhdoutput.master_clock_rate", 0);
 
-        if (outputuhd_conf.device.find("master_clock_rate") != std::string::npos) {
+        if (sdr_device_config.device.find("master_clock_rate") != std::string::npos) {
             std::cerr << "Warning:"
                 "setting master_clock_rate in [uhd] device is deprecated !\n";
         }
 
-        if (outputuhd_conf.device.find("type=") != std::string::npos) {
+        if (sdr_device_config.device.find("type=") != std::string::npos) {
             std::cerr << "Warning:"
                 "setting type in [uhd] device is deprecated !\n";
         }
 
-        outputuhd_conf.txgain = pt.get("uhdoutput.txgain", 0.0);
-        outputuhd_conf.rxgain = pt.get("uhdoutput.rxgain", 0.0);
-        outputuhd_conf.frequency = pt.get<double>("uhdoutput.frequency", 0);
+        sdr_device_config.txgain = pt.get("uhdoutput.txgain", 0.0);
+        sdr_device_config.tx_antenna = pt.get("uhdoutput.tx_antenna", "");
+        sdr_device_config.rx_antenna = pt.get("uhdoutput.rx_antenna", "RX2");
+        sdr_device_config.rxgain = pt.get("uhdoutput.rxgain", 0.0);
+        sdr_device_config.frequency = pt.get<double>("uhdoutput.frequency", 0);
         std::string chan = pt.get<std::string>("uhdoutput.channel", "");
-        outputuhd_conf.dabMode = mod_settings.dabMode;
+        sdr_device_config.dabMode = mod_settings.dabMode;
 
-        if (outputuhd_conf.frequency == 0 && chan == "") {
+        if (sdr_device_config.frequency == 0 && chan == "") {
             std::cerr << "       UHD output enabled, but neither frequency nor channel defined.\n";
             throw std::runtime_error("Configuration error");
         }
-        else if (outputuhd_conf.frequency == 0) {
-            outputuhd_conf.frequency = parseChannel(chan);
+        else if (sdr_device_config.frequency == 0) {
+            sdr_device_config.frequency = parseChannel(chan);
         }
-        else if (outputuhd_conf.frequency != 0 && chan != "") {
+        else if (sdr_device_config.frequency != 0 && chan != "") {
             std::cerr << "       UHD output: cannot define both frequency and channel.\n";
             throw std::runtime_error("Configuration error");
         }
 
-        outputuhd_conf.lo_offset = pt.get<double>("uhdoutput.lo_offset", 0);
+        sdr_device_config.lo_offset = pt.get<double>("uhdoutput.lo_offset", 0);
 
-        outputuhd_conf.refclk_src = pt.get("uhdoutput.refclk_source", "internal");
-        outputuhd_conf.pps_src = pt.get("uhdoutput.pps_source", "none");
-        outputuhd_conf.pps_polarity = pt.get("uhdoutput.pps_polarity", "pos");
+        sdr_device_config.refclk_src = pt.get("uhdoutput.refclk_source", "internal");
+        sdr_device_config.pps_src = pt.get("uhdoutput.pps_source", "none");
+        sdr_device_config.pps_polarity = pt.get("uhdoutput.pps_polarity", "pos");
 
         std::string behave = pt.get("uhdoutput.behaviour_refclk_lock_lost", "ignore");
 
         if (behave == "crash") {
-            outputuhd_conf.refclk_lock_loss_behaviour = CRASH;
+            sdr_device_config.refclk_lock_loss_behaviour = Output::CRASH;
         }
         else if (behave == "ignore") {
-            outputuhd_conf.refclk_lock_loss_behaviour = IGNORE;
+            sdr_device_config.refclk_lock_loss_behaviour = Output::IGNORE;
         }
         else {
             std::cerr << "Error: UHD output: behaviour_refclk_lock_lost invalid." << std::endl;
             throw std::runtime_error("Configuration error");
         }
 
-        outputuhd_conf.maxGPSHoldoverTime = pt.get("uhdoutput.max_gps_holdover_time", 0);
+        sdr_device_config.maxGPSHoldoverTime = pt.get("uhdoutput.max_gps_holdover_time", 0);
 
-        outputuhd_conf.dpdFeedbackServerPort = pt.get<long>("uhdoutput.dpd_port", 0);
+        sdr_device_config.dpdFeedbackServerPort = pt.get<long>("uhdoutput.dpd_port", 0);
 
-        mod_settings.outputuhd_conf = outputuhd_conf;
-        mod_settings.useUHDOutput = 1;
+        mod_settings.sdr_device_config = sdr_device_config;
+        mod_settings.useUHDOutput = true;
     }
 #endif
 #if defined(HAVE_SOAPYSDR)
     else if (output_selected == "soapysdr") {
-        auto& outputsoapy_conf = mod_settings.outputsoapy_conf;
+        auto& outputsoapy_conf = mod_settings.sdr_device_config;
         outputsoapy_conf.device = pt.get("soapyoutput.device", "");
         outputsoapy_conf.masterClockRate = pt.get<long>("soapyoutput.master_clock_rate", 0);
 
         outputsoapy_conf.txgain = pt.get("soapyoutput.txgain", 0.0);
+        outputsoapy_conf.tx_antenna = pt.get("soapyoutput.tx_antenna", "");
+        outputsoapy_conf.lo_offset = pt.get<double>("soapyoutput.lo_offset", 0.0);
         outputsoapy_conf.frequency = pt.get<double>("soapyoutput.frequency", 0);
         std::string chan = pt.get<std::string>("soapyoutput.channel", "");
         outputsoapy_conf.dabMode = mod_settings.dabMode;
@@ -299,14 +315,16 @@ static void parse_configfile(
             throw std::runtime_error("Configuration error");
         }
 
-        mod_settings.useSoapyOutput = 1;
+        outputsoapy_conf.dpdFeedbackServerPort = pt.get<long>("soapyoutput.dpd_port", 0);
+
+        mod_settings.useSoapyOutput = true;
     }
 #endif
 #if defined(HAVE_ZEROMQ)
     else if (output_selected == "zmq") {
         mod_settings.outputName = pt.get<std::string>("zmqoutput.listen");
         mod_settings.zmqOutputSocketType = pt.get<std::string>("zmqoutput.socket_type");
-        mod_settings.useZeroMQOutput = 1;
+        mod_settings.useZeroMQOutput = true;
     }
 #endif
     else {
@@ -315,9 +333,9 @@ static void parse_configfile(
     }
 
 #if defined(HAVE_OUTPUT_UHD)
-    mod_settings.outputuhd_conf.enableSync = (pt.get("delaymanagement.synchronous", 0) == 1);
-    mod_settings.outputuhd_conf.muteNoTimestamps = (pt.get("delaymanagement.mutenotimestamps", 0) == 1);
-    if (mod_settings.outputuhd_conf.enableSync) {
+    mod_settings.sdr_device_config.enableSync = (pt.get("delaymanagement.synchronous", 0) == 1);
+    mod_settings.sdr_device_config.muteNoTimestamps = (pt.get("delaymanagement.mutenotimestamps", 0) == 1);
+    if (mod_settings.sdr_device_config.enableSync) {
         std::string delay_mgmt = pt.get<std::string>("delaymanagement.management", "");
         std::string fixedoffset = pt.get<std::string>("delaymanagement.fixedoffset", "");
         std::string offset_filename = pt.get<std::string>("delaymanagement.dynamicoffsetfile", "");
@@ -388,11 +406,11 @@ void parse_args(int argc, char **argv, mod_settings_t& mod_settings)
             }
 #endif
             mod_settings.outputName = optarg;
-            mod_settings.useFileOutput = 1;
+            mod_settings.useFileOutput = true;
             break;
         case 'F':
 #if defined(HAVE_OUTPUT_UHD)
-            mod_settings.outputuhd_conf.frequency = strtof(optarg, NULL);
+            mod_settings.sdr_device_config.frequency = strtof(optarg, NULL);
 #endif
             break;
         case 'g':
@@ -400,7 +418,7 @@ void parse_args(int argc, char **argv, mod_settings_t& mod_settings)
             break;
         case 'G':
 #if defined(HAVE_OUTPUT_UHD)
-            mod_settings.outputuhd_conf.txgain = strtod(optarg, NULL);
+            mod_settings.sdr_device_config.txgain = strtod(optarg, NULL);
 #endif
             break;
         case 'l':
@@ -408,9 +426,7 @@ void parse_args(int argc, char **argv, mod_settings_t& mod_settings)
             break;
         case 'o':
             mod_settings.tist_offset_s = strtod(optarg, NULL);
-#if defined(HAVE_OUTPUT_UHD)
-            mod_settings.outputuhd_conf.enableSync = true;
-#endif
+            mod_settings.sdr_device_config.enableSync = true;
             break;
         case 'm':
             mod_settings.dabMode = strtol(optarg, NULL, 0);
@@ -427,11 +443,13 @@ void parse_args(int argc, char **argv, mod_settings_t& mod_settings)
                 fprintf(stderr, "Options -u and -f are mutually exclusive\n");
                 throw std::invalid_argument("Invalid command line options");
             }
-            mod_settings.outputuhd_conf.device = optarg;
-            mod_settings.outputuhd_conf.refclk_src = "internal";
-            mod_settings.outputuhd_conf.pps_src = "none";
-            mod_settings.outputuhd_conf.pps_polarity = "pos";
-            mod_settings.useUHDOutput = 1;
+            mod_settings.sdr_device_config.device = optarg;
+            mod_settings.sdr_device_config.refclk_src = "internal";
+            mod_settings.sdr_device_config.pps_src = "none";
+            mod_settings.sdr_device_config.pps_polarity = "pos";
+            mod_settings.useUHDOutput = true;
+#else
+            throw std::invalid_argument("Cannot select UHD output, not compiled in!");
 #endif
             break;
         case 'V':
diff --git a/src/ConfigParser.h b/src/ConfigParser.h
index 0be3558..dc5ac4f 100644
--- a/src/ConfigParser.h
+++ b/src/ConfigParser.h
@@ -34,23 +34,21 @@
 #include <string>
 #include "GainControl.h"
 #include "TII.h"
-#if defined(HAVE_OUTPUT_UHD)
-#   include "OutputUHD.h"
-#endif
-#if defined(HAVE_SOAPYSDR)
-#   include "OutputSoapy.h"
-#endif
+#include "output/SDR.h"
+#include "output/UHD.h"
+#include "output/Soapy.h"
 
 #define ZMQ_INPUT_MAX_FRAME_QUEUE 500
 
 struct mod_settings_t {
     std::string outputName;
-    int useZeroMQOutput = 0;
+    bool useZeroMQOutput = false;
     std::string zmqOutputSocketType = "";
-    int useFileOutput = 0;
+    bool useFileOutput = false;
     std::string fileOutputFormat = "complexf";
-    int useUHDOutput = 0;
-    int useSoapyOutput = 0;
+    bool fileOutputShowMetadata = false;
+    bool useUHDOutput = false;
+    bool useSoapyOutput = false;
 
     size_t outputRate = 2048000;
     size_t clockRate = 0;
@@ -61,7 +59,6 @@ struct mod_settings_t {
     float gainmodeVariance = 4.0f;
 
     // To handle the timestamp offset of the modulator
-    unsigned tist_delay_stages = 1; // because GainControl is pipelined
     double tist_offset_s = 0.0;
 
     bool loop = false;
@@ -85,12 +82,8 @@ struct mod_settings_t {
     // Settings for the OFDM windowing
     unsigned ofdmWindowOverlap = 0;
 
-#if defined(HAVE_OUTPUT_UHD)
-    OutputUHDConfig outputuhd_conf;
-#endif
-
-#if defined(HAVE_SOAPYSDR)
-    OutputSoapyConfig outputsoapy_conf;
+#if defined(HAVE_OUTPUT_UHD) || defined(HAVE_SOAPYSDR)
+    Output::SDRDeviceConfig sdr_device_config;
 #endif
 
 };
diff --git a/src/DabMod.cpp b/src/DabMod.cpp
index 25a93bf..8a0ee03 100644
--- a/src/DabMod.cpp
+++ b/src/DabMod.cpp
@@ -37,12 +37,9 @@
 #include "OutputFile.h"
 #include "FormatConverter.h"
 #include "FrameMultiplexer.h"
-#if defined(HAVE_OUTPUT_UHD)
-#   include "OutputUHD.h"
-#endif
-#if defined(HAVE_SOAPYSDR)
-#   include "OutputSoapy.h"
-#endif
+#include "output/SDR.h"
+#include "output/UHD.h"
+#include "output/Soapy.h"
 #include "OutputZeroMQ.h"
 #include "InputReader.h"
 #include "PcDebug.h"
@@ -95,18 +92,12 @@ void signalHandler(int signalNb)
 
 struct modulator_data
 {
-    modulator_data() :
-        inputReader(nullptr),
-        framecount(0),
-        flowgraph(nullptr),
-        etiReader(nullptr) {}
-
-    InputReader* inputReader;
+    std::shared_ptr<InputReader> inputReader;
     Buffer data;
-    uint64_t framecount;
+    uint64_t framecount = 0;
 
-    Flowgraph* flowgraph;
-    EtiReader* etiReader;
+    Flowgraph* flowgraph = nullptr;
+    EtiReader* etiReader = nullptr;
 };
 
 enum class run_modulator_state_t {
@@ -116,7 +107,7 @@ enum class run_modulator_state_t {
     reconfigure // Some sort of change of configuration we cannot handle happened
 };
 
-run_modulator_state_t run_modulator(modulator_data& m);
+static run_modulator_state_t run_modulator(modulator_data& m);
 
 static void printModSettings(const mod_settings_t& mod_settings)
 {
@@ -133,15 +124,15 @@ static void printModSettings(const mod_settings_t& mod_settings)
     else if (mod_settings.useUHDOutput) {
         fprintf(stderr, " UHD\n"
                         "  Device: %s\n"
-                        "  Type: %s\n"
+                        "  Subdevice: %s\n"
                         "  master_clock_rate: %ld\n"
                         "  refclk: %s\n"
                         "  pps source: %s\n",
-                mod_settings.outputuhd_conf.device.c_str(),
-                mod_settings.outputuhd_conf.usrpType.c_str(),
-                mod_settings.outputuhd_conf.masterClockRate,
-                mod_settings.outputuhd_conf.refclk_src.c_str(),
-                mod_settings.outputuhd_conf.pps_src.c_str());
+                mod_settings.sdr_device_config.device.c_str(),
+                mod_settings.sdr_device_config.subDevice.c_str(),
+                mod_settings.sdr_device_config.masterClockRate,
+                mod_settings.sdr_device_config.refclk_src.c_str(),
+                mod_settings.sdr_device_config.pps_src.c_str());
     }
 #endif
 #if defined(HAVE_SOAPYSDR)
@@ -149,8 +140,8 @@ static void printModSettings(const mod_settings_t& mod_settings)
         fprintf(stderr, " SoapySDR\n"
                         "  Device: %s\n"
                         "  master_clock_rate: %ld\n",
-                mod_settings.outputsoapy_conf.device.c_str(),
-                mod_settings.outputsoapy_conf.masterClockRate);
+                mod_settings.sdr_device_config.device.c_str(),
+                mod_settings.sdr_device_config.masterClockRate);
     }
 #endif
     else if (mod_settings.useZeroMQOutput) {
@@ -180,7 +171,7 @@ static shared_ptr<ModOutput> prepare_output(
 
     if (s.useFileOutput) {
         if (s.fileOutputFormat == "complexf") {
-            output = make_shared<OutputFile>(s.outputName);
+            output = make_shared<OutputFile>(s.outputName, s.fileOutputShowMetadata);
         }
         else if (s.fileOutputFormat == "complexf_normalised") {
             if (s.gainMode == GainMode::GAIN_FIX)
@@ -189,7 +180,7 @@ static shared_ptr<ModOutput> prepare_output(
                 s.normalise = 1.0f / normalise_factor_file_max;
             else if (s.gainMode == GainMode::GAIN_VAR)
                 s.normalise = 1.0f / normalise_factor_file_var;
-            output = make_shared<OutputFile>(s.outputName);
+            output = make_shared<OutputFile>(s.outputName, s.fileOutputShowMetadata);
         }
         else if (s.fileOutputFormat == "s8" or
                 s.fileOutputFormat == "u8") {
@@ -198,7 +189,7 @@ static shared_ptr<ModOutput> prepare_output(
             // [0; 255]
             s.normalise = 127.0f / normalise_factor;
 
-            output = make_shared<OutputFile>(s.outputName);
+            output = make_shared<OutputFile>(s.outputName, s.fileOutputShowMetadata);
         }
         else {
             throw runtime_error("File output format " + s.fileOutputFormat +
@@ -208,18 +199,20 @@ static shared_ptr<ModOutput> prepare_output(
 #if defined(HAVE_OUTPUT_UHD)
     else if (s.useUHDOutput) {
         s.normalise = 1.0f / normalise_factor;
-        s.outputuhd_conf.sampleRate = s.outputRate;
-        output = make_shared<OutputUHD>(s.outputuhd_conf);
-        rcs.enrol((OutputUHD*)output.get());
+        s.sdr_device_config.sampleRate = s.outputRate;
+        auto uhddevice = make_shared<Output::UHD>(s.sdr_device_config);
+        output = make_shared<Output::SDR>(s.sdr_device_config, uhddevice);
+        rcs.enrol((Output::SDR*)output.get());
     }
 #endif
 #if defined(HAVE_SOAPYSDR)
     else if (s.useSoapyOutput) {
         /* We normalise the same way as for the UHD output */
         s.normalise = 1.0f / normalise_factor;
-        s.outputsoapy_conf.sampleRate = s.outputRate;
-        output = make_shared<OutputSoapy>(s.outputsoapy_conf);
-        rcs.enrol((OutputSoapy*)output.get());
+        s.sdr_device_config.sampleRate = s.outputRate;
+        auto soapydevice = make_shared<Output::Soapy>(s.sdr_device_config);
+        output = make_shared<Output::SDR>(s.sdr_device_config, soapydevice);
+        rcs.enrol((Output::SDR*)output.get());
     }
 #endif
 #if defined(HAVE_ZEROMQ)
@@ -270,16 +263,8 @@ int launch_modulator(int argc, char* argv[])
         throw std::runtime_error("Configuration error");
     }
 
-    // When using the FIRFilter, increase the modulator offset pipelining delay
-    // by the correct amount
-    if (not mod_settings.filterTapsFilename.empty()) {
-        mod_settings.tist_delay_stages += FIRFILTER_PIPELINE_DELAY;
-    }
-
     printModSettings(mod_settings);
 
-    modulator_data m;
-
     shared_ptr<FormatConverter> format_converter;
     if (mod_settings.useFileOutput and
             (mod_settings.fileOutputFormat == "s8" or
@@ -296,7 +281,7 @@ int launch_modulator(int argc, char* argv[])
     set_thread_name("modulator");
 
     if (mod_settings.inputTransport == "edi") {
-        EdiReader ediReader(mod_settings.tist_offset_s, mod_settings.tist_delay_stages);
+        EdiReader ediReader(mod_settings.tist_offset_s);
         EdiDecoder::ETIDecoder ediInput(ediReader, false);
         if (mod_settings.edi_max_delay_ms > 0.0f) {
             // setMaxDelay wants number of AF packets, which correspond to 24ms ETI frames
@@ -321,17 +306,6 @@ int launch_modulator(int argc, char* argv[])
             flowgraph.connect(modulator, output);
         }
 
-#if defined(HAVE_OUTPUT_UHD)
-        if (mod_settings.useUHDOutput) {
-            ((OutputUHD*)output.get())->setETISource(modulator->getEtiSource());
-        }
-#endif
-#if defined(HAVE_SOAPYSDR)
-        if (mod_settings.useSoapyOutput) {
-            ((OutputSoapy*)output.get())->setETISource(modulator->getEtiSource());
-        }
-#endif
-
         size_t framecount = 0;
 
         while (running) {
@@ -397,11 +371,12 @@ int launch_modulator(int argc, char* argv[])
         while (run_again) {
             Flowgraph flowgraph;
 
-            m.inputReader = inputReader.get();
+            modulator_data m;
+            m.inputReader = inputReader;
             m.flowgraph = &flowgraph;
             m.data.setLength(6144);
 
-            EtiReader etiReader(mod_settings.tist_offset_s, mod_settings.tist_delay_stages);
+            EtiReader etiReader(mod_settings.tist_offset_s);
             m.etiReader = &etiReader;
 
             auto input = make_shared<InputMemory>(&m.data);
@@ -415,17 +390,6 @@ int launch_modulator(int argc, char* argv[])
                 flowgraph.connect(modulator, output);
             }
 
-#if defined(HAVE_OUTPUT_UHD)
-            if (mod_settings.useUHDOutput) {
-                ((OutputUHD*)output.get())->setETISource(modulator->getEtiSource());
-            }
-#endif
-#if defined(HAVE_SOAPYSDR)
-            if (mod_settings.useSoapyOutput) {
-                ((OutputSoapy*)output.get())->setETISource(modulator->getEtiSource());
-            }
-#endif
-
             inputReader->PrintInfo();
 
             run_modulator_state_t st = run_modulator(m);
@@ -490,7 +454,7 @@ int launch_modulator(int argc, char* argv[])
     return ret;
 }
 
-run_modulator_state_t run_modulator(modulator_data& m)
+static run_modulator_state_t run_modulator(modulator_data& m)
 {
     auto ret = run_modulator_state_t::failure;
     try {
@@ -527,13 +491,26 @@ run_modulator_state_t run_modulator(modulator_data& m)
                 }
             }
             if (framesize == 0) {
-                etiLog.level(info) << "End of file reached.";
+                if (dynamic_pointer_cast<InputFileReader>(m.inputReader)) {
+                    etiLog.level(info) << "End of file reached.";
+                    running = 0;
+                    ret = run_modulator_state_t::normal_end;
+                }
+#if defined(HAVE_ZEROMQ)
+                else if (dynamic_pointer_cast<InputZeroMQReader>(m.inputReader)) {
+                    /* An empty frame marks a timeout. We ignore it, but we are
+                     * now able to handle SIGINT properly.
+                     */
+                }
+#endif // defined(HAVE_ZEROMQ)
+                // No need to handle the TCP input in a special way to get SIGINT working,
+                // because recv() will return with EINTR.
             }
             else {
                 etiLog.level(error) << "Input read error.";
+                running = 0;
+                ret = run_modulator_state_t::normal_end;
             }
-            running = 0;
-            ret = run_modulator_state_t::normal_end;
         }
     }
     catch (const zmq_input_overflow& e) {
diff --git a/src/DabModulator.cpp b/src/DabModulator.cpp
index 8ba8af6..5b77d18 100644
--- a/src/DabModulator.cpp
+++ b/src/DabModulator.cpp
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -162,10 +162,13 @@ int DabModulator::process(Buffer* dataOut)
             }
         }
 
-        auto cifCicEq = make_shared<CicEqualizer>(
+        shared_ptr<CicEqualizer> cifCicEq;
+        if (useCicEq) {
+            cifCicEq = make_shared<CicEqualizer>(
                 myNbCarriers,
                 (float)mySpacing * (float)m_settings.outputRate / 2048000.0f,
                 cic_ratio);
+        }
 
         shared_ptr<TII> tii;
         shared_ptr<PhaseReference> tiiRef;
@@ -218,7 +221,7 @@ int DabModulator::process(Buffer* dataOut)
             rcs.enrol(cifPoly.get());
         }
 
-        auto myOutput = make_shared<OutputMemory>(dataOut);
+        myOutput = make_shared<OutputMemory>(dataOut);
 
         shared_ptr<Resampler> cifRes;
         if (m_settings.outputRate != 2048000) {
@@ -347,43 +350,24 @@ int DabModulator::process(Buffer* dataOut)
             myFlowgraph->connect(tii, cifSig);
         }
 
-        if (useCicEq) {
-            myFlowgraph->connect(cifSig, cifCicEq);
-            myFlowgraph->connect(cifCicEq, cifOfdm);
-        }
-        else {
-            myFlowgraph->connect(cifSig, cifOfdm);
-        }
-        myFlowgraph->connect(cifOfdm, cifGain);
-        myFlowgraph->connect(cifGain, cifGuard);
-
-        auto cifOut = cifPoly ?
-            static_pointer_cast<ModPlugin>(cifPoly) :
-            static_pointer_cast<ModPlugin>(myOutput);
-
-        if (cifFilter) {
-            myFlowgraph->connect(cifGuard, cifFilter);
-            if (cifRes) {
-                myFlowgraph->connect(cifFilter, cifRes);
-                myFlowgraph->connect(cifRes, cifOut);
-            }
-            else {
-                myFlowgraph->connect(cifFilter, cifOut);
-            }
-        }
-        else {
-            if (cifRes) {
-                myFlowgraph->connect(cifGuard, cifRes);
-                myFlowgraph->connect(cifRes, cifOut);
-            }
-            else {
-                myFlowgraph->connect(cifGuard, cifOut);
+        shared_ptr<ModPlugin> prev_plugin = static_pointer_cast<ModPlugin>(cifSig);
+        const std::list<shared_ptr<ModPlugin> > plugins({
+                static_pointer_cast<ModPlugin>(cifCicEq),
+                static_pointer_cast<ModPlugin>(cifOfdm),
+                static_pointer_cast<ModPlugin>(cifGain),
+                static_pointer_cast<ModPlugin>(cifGuard),
+                static_pointer_cast<ModPlugin>(cifFilter), // optional block
+                static_pointer_cast<ModPlugin>(cifRes),    // optional block
+                static_pointer_cast<ModPlugin>(cifPoly),   // optional block
+                static_pointer_cast<ModPlugin>(myOutput),
+                });
+
+        for (auto& p : plugins) {
+            if (p) {
+                myFlowgraph->connect(prev_plugin, p);
+                prev_plugin = p;
             }
         }
-
-        if (cifPoly) {
-            myFlowgraph->connect(cifPoly, myOutput);
-        }
     }
 
     ////////////////////////////////////////////////////////////////////
@@ -392,3 +376,12 @@ int DabModulator::process(Buffer* dataOut)
     return myFlowgraph->run();
 }
 
+meta_vec_t DabModulator::process_metadata(const meta_vec_t& metadataIn)
+{
+    if (myOutput) {
+        return myOutput->get_latest_metadata();
+    }
+
+    return {};
+}
+
diff --git a/src/DabModulator.h b/src/DabModulator.h
index 2d7bc35..e84ce96 100644
--- a/src/DabModulator.h
+++ b/src/DabModulator.h
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -46,7 +46,7 @@
 #include "TII.h"
 
 
-class DabModulator : public ModInput
+class DabModulator : public ModInput, public ModMetadata
 {
 public:
     DabModulator(EtiSource& etiSource,
@@ -55,6 +55,9 @@ public:
     int process(Buffer* dataOut);
     const char* name() { return "DabModulator"; }
 
+    virtual meta_vec_t process_metadata(
+            const meta_vec_t& metadataIn);
+
     /* Required to get the timestamp */
     EtiSource* getEtiSource() { return &myEtiSource; }
 
diff --git a/src/EtiReader.cpp b/src/EtiReader.cpp
index d84ed1f..17f4953 100644
--- a/src/EtiReader.cpp
+++ b/src/EtiReader.cpp
@@ -54,10 +54,9 @@ enum ETI_READER_STATE {
 
 
 EtiReader::EtiReader(
-        double& tist_offset_s,
-        unsigned tist_delay_stages) :
+        double& tist_offset_s) :
     state(EtiReaderStateSync),
-    myTimestampDecoder(tist_offset_s, tist_delay_stages),
+    myTimestampDecoder(tist_offset_s),
     eti_fc_valid(false)
 {
     rcs.enrol(&myTimestampDecoder);
@@ -281,6 +280,8 @@ int EtiReader::loadEtiData(const Buffer& dataIn)
     myTimestampDecoder.updateTimestampEti(eti_fc.FP & 0x3,
             eti_eoh.MNSC, getPPSOffset(), eti_fc.FCT);
 
+    myFicSource->loadTimestamp(myTimestampDecoder.getTimestamp());
+
     return dataIn.getLength() - input_size;
 }
 
@@ -290,11 +291,6 @@ bool EtiReader::sourceContainsTimestamp()
     /* See ETS 300 799, Annex C.2.2 */
 }
 
-void EtiReader::calculateTimestamp(struct frame_timestamp& ts)
-{
-    myTimestampDecoder.calculateTimestamp(ts);
-}
-
 uint32_t EtiReader::getPPSOffset()
 {
     if (!sourceContainsTimestamp()) {
@@ -309,9 +305,8 @@ uint32_t EtiReader::getPPSOffset()
 }
 
 EdiReader::EdiReader(
-        double& tist_offset_s,
-        unsigned tist_delay_stages) :
-    m_timestamp_decoder(tist_offset_s, tist_delay_stages)
+        double& tist_offset_s) :
+    m_timestamp_decoder(tist_offset_s)
 {
     rcs.enrol(&m_timestamp_decoder);
 }
@@ -359,11 +354,6 @@ bool EdiReader::sourceContainsTimestamp()
     return m_fc.tsta != 0xFFFFFF;
 }
 
-void EdiReader::calculateTimestamp(struct frame_timestamp& ts)
-{
-    m_timestamp_decoder.calculateTimestamp(ts);
-}
-
 bool EdiReader::isFrameReady()
 {
     return m_frameReady;
@@ -533,8 +523,9 @@ void EdiReader::assemble()
     const std::time_t posix_timestamp_1_jan_2000 = 946684800;
     auto utc_ts = posix_timestamp_1_jan_2000 + m_seconds - m_utco;
 
-    m_timestamp_decoder.updateTimestampEdi(
-            utc_ts, m_fc.tsta, m_fc.fct());
+    m_timestamp_decoder.updateTimestampEdi(utc_ts, m_fc.tsta, m_fc.fct(), m_fc.fp);
+
+    myFicSource->loadTimestamp(m_timestamp_decoder.getTimestamp());
 
     m_frameReady = true;
 }
diff --git a/src/EtiReader.h b/src/EtiReader.h
index f3a9764..8270592 100644
--- a/src/EtiReader.h
+++ b/src/EtiReader.h
@@ -59,7 +59,6 @@ public:
 
     /* Returns true if we have valid time stamps in the ETI*/
     virtual bool sourceContainsTimestamp() = 0;
-    virtual void calculateTimestamp(struct frame_timestamp& ts) = 0;
 
     /* Return the FIC source to be used for modulation */
     virtual std::shared_ptr<FicSource>& getFic(void);
@@ -75,9 +74,7 @@ protected:
 class EtiReader : public EtiSource
 {
 public:
-    EtiReader(
-            double& tist_offset_s,
-            unsigned tist_delay_stages);
+    EtiReader(double& tist_offset_s);
 
     virtual unsigned getMode();
     virtual unsigned getFp();
@@ -88,7 +85,6 @@ public:
     int loadEtiData(const Buffer& dataIn);
 
     virtual bool sourceContainsTimestamp();
-    virtual void calculateTimestamp(struct frame_timestamp& ts);
 
     virtual const std::vector<std::shared_ptr<SubchannelSource> > getSubchannels() const;
 
@@ -118,14 +114,11 @@ private:
 class EdiReader : public EtiSource, public EdiDecoder::DataCollector
 {
 public:
-    EdiReader(
-            double& tist_offset_s,
-            unsigned tist_delay_stages);
+    EdiReader(double& tist_offset_s);
 
     virtual unsigned getMode();
     virtual unsigned getFp();
     virtual bool sourceContainsTimestamp();
-    virtual void calculateTimestamp(struct frame_timestamp& ts);
     virtual const std::vector<std::shared_ptr<SubchannelSource> > getSubchannels() const;
 
     virtual bool isFrameReady(void);
diff --git a/src/FIRFilter.cpp b/src/FIRFilter.cpp
index bc2314a..96ad1b9 100644
--- a/src/FIRFilter.cpp
+++ b/src/FIRFilter.cpp
@@ -87,6 +87,11 @@ FIRFilter::FIRFilter(const std::string& taps_file) :
     start_pipeline_thread();
 }
 
+FIRFilter::~FIRFilter()
+{
+    stop_pipeline_thread();
+}
+
 void FIRFilter::load_filter_taps(const std::string &tapsFile)
 {
     std::vector<float> filter_taps;
diff --git a/src/FIRFilter.h b/src/FIRFilter.h
index a63bfb9..d04c456 100644
--- a/src/FIRFilter.h
+++ b/src/FIRFilter.h
@@ -53,20 +53,21 @@ class FIRFilter : public PipelinedModCodec, public RemoteControllable
 {
 public:
     FIRFilter(const std::string& taps_file);
-    virtual ~FIRFilter() = default;
+    FIRFilter(const FIRFilter& other) = delete;
+    FIRFilter& operator=(const FIRFilter& other) = delete;
+    virtual ~FIRFilter();
 
-    const char* name() { return "FIRFilter"; }
+    const char* name() override { return "FIRFilter"; }
 
     /******* REMOTE CONTROL ********/
     virtual void set_parameter(const std::string& parameter,
-            const std::string& value);
+            const std::string& value) override;
 
     virtual const std::string get_parameter(
-            const std::string& parameter) const;
-
+            const std::string& parameter) const override;
 
 protected:
-    virtual int internal_process(Buffer* const dataIn, Buffer* dataOut);
+    virtual int internal_process(Buffer* const dataIn, Buffer* dataOut) override;
     void load_filter_taps(const std::string &tapsFile);
 
     std::string m_taps_file;
diff --git a/src/FicSource.cpp b/src/FicSource.cpp
index 04197db..2b95085 100644
--- a/src/FicSource.cpp
+++ b/src/FicSource.cpp
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -26,6 +26,8 @@
 
 #include "FicSource.h"
 #include "PcDebug.h"
+#include "Log.h"
+#include "TimestampDecoder.h"
 
 #include <stdexcept>
 #include <string>
@@ -92,3 +94,23 @@ int FicSource::process(Buffer* outputData)
     return outputData->getLength();
 }
 
+void FicSource::loadTimestamp(const std::shared_ptr<struct frame_timestamp>& ts)
+{
+    d_ts = ts;
+}
+
+
+meta_vec_t FicSource::process_metadata(const meta_vec_t& metadataIn)
+{
+    if (not d_ts) {
+        return {};
+    }
+
+    using namespace std;
+    meta_vec_t md_vec;
+    flowgraph_metadata meta;
+    meta.ts = d_ts;
+    md_vec.push_back(meta);
+    return md_vec;
+}
+
diff --git a/src/FicSource.h b/src/FicSource.h
index 77ac741..93c1a7f 100644
--- a/src/FicSource.h
+++ b/src/FicSource.h
@@ -36,7 +36,7 @@
 #include <vector>
 #include <sys/types.h>
 
-class FicSource : public ModInput
+class FicSource : public ModInput, public ModMetadata
 {
 public:
     FicSource(unsigned ficf, unsigned mid);
@@ -45,12 +45,17 @@ public:
     const std::vector<PuncturingRule>& get_rules();
 
     void loadFicData(const Buffer& fic);
-    int process(Buffer* outputData);
-    const char* name() { return "FicSource"; }
+    int process(Buffer* outputData) override;
+    const char* name() override { return "FicSource"; }
+
+    void loadTimestamp(const std::shared_ptr<struct frame_timestamp>& ts);
+    virtual meta_vec_t process_metadata(
+            const meta_vec_t& metadataIn) override;
 
 private:
     size_t d_framesize;
     Buffer d_buffer;
+    std::shared_ptr<struct frame_timestamp> d_ts;
     std::vector<PuncturingRule> d_puncturing_rules;
 };
 
diff --git a/src/Flowgraph.cpp b/src/Flowgraph.cpp
index 465ef41..506832c 100644
--- a/src/Flowgraph.cpp
+++ b/src/Flowgraph.cpp
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -26,6 +26,7 @@
 
 #include "Flowgraph.h"
 #include "PcDebug.h"
+#include "Log.h"
 #include <string>
 #include <memory>
 #include <algorithm>
@@ -57,9 +58,10 @@ Node::~Node()
     assert(myOutputBuffers.size() == 0);
 }
 
-void Node::addOutputBuffer(Buffer::sptr& buffer)
+void Node::addOutputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md)
 {
     myOutputBuffers.push_back(buffer);
+    myOutputMetadata.push_back(md);
 #if DEBUG
     std::string fname = string(myPlugin->name()) +
         "-" + to_string(myDebugFiles.size()) +
@@ -71,7 +73,7 @@ void Node::addOutputBuffer(Buffer::sptr& buffer)
 #endif
 }
 
-void Node::removeOutputBuffer(Buffer::sptr& buffer)
+void Node::removeOutputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md)
 {
     auto it = std::find(
             myOutputBuffers.begin(),
@@ -89,14 +91,23 @@ void Node::removeOutputBuffer(Buffer::sptr& buffer)
 #endif
         myOutputBuffers.erase(it);
     }
+
+    auto mdit = std::find(
+            myOutputMetadata.begin(),
+            myOutputMetadata.end(),
+            md);
+    if (mdit != myOutputMetadata.end()) {
+        myOutputMetadata.erase(mdit);
+    }
 }
 
-void Node::addInputBuffer(Buffer::sptr& buffer)
+void Node::addInputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md)
 {
     myInputBuffers.push_back(buffer);
+    myInputMetadata.push_back(md);
 }
 
-void Node::removeInputBuffer(Buffer::sptr& buffer)
+void Node::removeInputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md)
 {
     auto it = std::find(
             myInputBuffers.begin(),
@@ -105,6 +116,14 @@ void Node::removeInputBuffer(Buffer::sptr& buffer)
     if (it != myInputBuffers.end()) {
         myInputBuffers.erase(it);
     }
+
+    auto mdit = std::find(
+            myInputMetadata.begin(),
+            myInputMetadata.end(),
+            md);
+    if (mdit != myInputMetadata.end()) {
+        myInputMetadata.erase(mdit);
+    }
 }
 
 int Node::process()
@@ -127,6 +146,37 @@ int Node::process()
     }
 
     int ret = myPlugin->process(inBuffers, outBuffers);
+
+    // Collect all incoming metadata into a single vector
+    meta_vec_t all_input_mds;
+    for (auto& md_vec_sp : myInputMetadata) {
+        if (md_vec_sp) {
+            move(md_vec_sp->begin(), md_vec_sp->end(),
+                    back_inserter(all_input_mds));
+            md_vec_sp->clear();
+        }
+    }
+
+    auto mod_meta = dynamic_pointer_cast<ModMetadata>(myPlugin);
+    if (mod_meta) {
+        auto outputMetadata = mod_meta->process_metadata(all_input_mds);
+        // Distribute the result metadata to all outputs
+        for (auto& out_md : myOutputMetadata) {
+            out_md->clear();
+            std::move(outputMetadata.begin(), outputMetadata.end(),
+                    std::back_inserter(*out_md));
+        }
+    }
+    else {
+        // Propagate the unmodified input metadata to all outputs
+        for (auto& out_md : myOutputMetadata) {
+            out_md->clear();
+            std::move(all_input_mds.begin(), all_input_mds.end(),
+                    std::back_inserter(*out_md));
+        }
+    }
+
+
 #if DEBUG
     assert(myDebugFiles.size() == myOutputBuffers.size());
 
@@ -158,8 +208,10 @@ Edge::Edge(shared_ptr<Node>& srcNode, shared_ptr<Node>& dstNode) :
             this);
 
     myBuffer = make_shared<Buffer>();
-    srcNode->addOutputBuffer(myBuffer);
-    dstNode->addInputBuffer(myBuffer);
+    myMetadata = make_shared<vector<flowgraph_metadata> >();
+
+    srcNode->addOutputBuffer(myBuffer, myMetadata);
+    dstNode->addInputBuffer(myBuffer, myMetadata);
 }
 
 
@@ -168,8 +220,8 @@ Edge::~Edge()
     PDEBUG("Edge::~Edge() @ %p\n", this);
 
     if (myBuffer) {
-        mySrcNode->removeOutputBuffer(myBuffer);
-        myDstNode->removeInputBuffer(myBuffer);
+        mySrcNode->removeOutputBuffer(myBuffer, myMetadata);
+        myDstNode->removeInputBuffer(myBuffer, myMetadata);
     }
 }
 
@@ -186,9 +238,8 @@ Flowgraph::~Flowgraph()
 {
     PDEBUG("Flowgraph::~Flowgraph() @ %p\n", this);
 
-    stringstream ss;
-
     if (myProcessTime) {
+        stringstream ss;
         ss << "Process time:\n";
 
         char node_time_sz[1024] = {};
diff --git a/src/Flowgraph.h b/src/Flowgraph.h
index ebb7314..b074ee6 100644
--- a/src/Flowgraph.h
+++ b/src/Flowgraph.h
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -39,6 +39,8 @@
 #include <list>
 #include <cstdio>
 
+using Metadata_vec_sptr = std::shared_ptr<std::vector<flowgraph_metadata> >;
+
 class Node
 {
 public:
@@ -55,15 +57,18 @@ public:
         myProcessTime += processTime;
     }
 
-    void addOutputBuffer(Buffer::sptr& buffer);
-    void removeOutputBuffer(Buffer::sptr& buffer);
+    void addOutputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md);
+    void removeOutputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md);
 
-    void addInputBuffer(Buffer::sptr& buffer);
-    void removeInputBuffer(Buffer::sptr& buffer);
+    void addInputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md);
+    void removeInputBuffer(Buffer::sptr& buffer, Metadata_vec_sptr& md);
 
 protected:
     std::list<Buffer::sptr> myInputBuffers;
     std::list<Buffer::sptr> myOutputBuffers;
+    std::list<Metadata_vec_sptr> myInputMetadata;
+    std::list<Metadata_vec_sptr> myOutputMetadata;
+
 #if DEBUG
     std::list<FILE*> myDebugFiles;
 #endif
@@ -85,6 +90,7 @@ protected:
     std::shared_ptr<Node> mySrcNode;
     std::shared_ptr<Node> myDstNode;
     std::shared_ptr<Buffer> myBuffer;
+    std::shared_ptr<std::vector<flowgraph_metadata> > myMetadata;
 };
 
 
diff --git a/src/GainControl.cpp b/src/GainControl.cpp
index 0411482..5657fc2 100644
--- a/src/GainControl.cpp
+++ b/src/GainControl.cpp
@@ -75,7 +75,7 @@ GainControl::GainControl(size_t framesize,
 
 GainControl::~GainControl()
 {
-    PDEBUG("GainControl::~GainControl() @ %p\n", this);
+    stop_pipeline_thread();
 }
 
 int GainControl::internal_process(Buffer* const dataIn, Buffer* dataOut)
diff --git a/src/GainControl.h b/src/GainControl.h
index e9eaa8c..b4579cd 100644
--- a/src/GainControl.h
+++ b/src/GainControl.h
@@ -57,8 +57,8 @@ class GainControl : public PipelinedModCodec, public RemoteControllable
                     float varVariance);
 
         virtual ~GainControl();
-        GainControl(const GainControl&);
-        GainControl& operator=(const GainControl&);
+        GainControl(const GainControl&) = delete;
+        GainControl& operator=(const GainControl&) = delete;
 
         const char* name() override { return "GainControl"; }
 
diff --git a/src/GuardIntervalInserter.cpp b/src/GuardIntervalInserter.cpp
index afb9213..79692f5 100644
--- a/src/GuardIntervalInserter.cpp
+++ b/src/GuardIntervalInserter.cpp
@@ -97,8 +97,6 @@ void GuardIntervalInserter::update_window(size_t new_window_overlap)
     }
 }
 
-#pragma GCC optimize ("O0")
-
 int GuardIntervalInserter::process(Buffer* const dataIn, Buffer* dataOut)
 {
     PDEBUG("GuardIntervalInserter::process(dataIn: %p, dataOut: %p)\n",
diff --git a/src/InputFileReader.cpp b/src/InputFileReader.cpp
index 84f0be4..5e93477 100644
--- a/src/InputFileReader.cpp
+++ b/src/InputFileReader.cpp
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyrigth (C) 2013
+   Copyrigth (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
 
@@ -47,28 +47,29 @@ int InputFileReader::Open(std::string filename, bool loop)
 {
     filename_ = filename;
     loop_ = loop;
-    inputfile_ = fopen(filename_.c_str(), "r");
-    if (inputfile_ == NULL) {
+    FILE* fd = fopen(filename_.c_str(), "r");
+    if (fd == nullptr) {
         etiLog.level(error) << "Unable to open input file!";
         perror(filename_.c_str());
         return -1;
     }
+    inputfile_.reset(fd);
 
     return IdentifyType();
 }
 
 int InputFileReader::Rewind()
 {
-    rewind(inputfile_); // Also clears the EOF flag
+    rewind(inputfile_.get()); // Also clears the EOF flag
     return IdentifyType();
 }
 
 int InputFileReader::IdentifyType()
 {
-    EtiStreamType streamType = ETI_STREAM_TYPE_NONE;
+    EtiStreamType streamType = EtiStreamType::None;
 
     struct stat inputFileStat;
-    fstat(fileno(inputfile_), &inputFileStat);
+    fstat(fileno(inputfile_.get()), &inputFileStat);
     inputfilelength_ = inputFileStat.st_size;
 
     uint32_t sync;
@@ -77,22 +78,22 @@ int InputFileReader::IdentifyType()
 
     char discard_buffer[6144];
 
-    if (fread(&sync, sizeof(sync), 1, inputfile_) != 1) {
+    if (fread(&sync, sizeof(sync), 1, inputfile_.get()) != 1) {
         etiLog.level(error) << "Unable to read sync in input file!";
         perror(filename_.c_str());
         return -1;
     }
     if ((sync == 0x49c5f8ff) || (sync == 0xb63a07ff)) {
-        streamType = ETI_STREAM_TYPE_RAW;
+        streamType = EtiStreamType::Raw;
         if (inputfilelength_ > 0) {
             nbframes_ = inputfilelength_ / 6144;
         }
         else {
             nbframes_ = ~0;
         }
-        if (fseek(inputfile_, -sizeof(sync), SEEK_CUR) != 0) {
+        if (fseek(inputfile_.get(), -sizeof(sync), SEEK_CUR) != 0) {
             // if the seek fails, consume the rest of the frame
-            if (fread(discard_buffer, 6144 - sizeof(sync), 1, inputfile_)
+            if (fread(discard_buffer, 6144 - sizeof(sync), 1, inputfile_.get())
                     != 1) {
                 etiLog.level(error) << "Unable to read from input file!";
                 perror(filename_.c_str());
@@ -104,7 +105,7 @@ int InputFileReader::IdentifyType()
     }
 
     nbFrames = sync;
-    if (fread(&frameSize, sizeof(frameSize), 1, inputfile_) != 1) {
+    if (fread(&frameSize, sizeof(frameSize), 1, inputfile_.get()) != 1) {
         etiLog.level(error) << "Unable to read frame size in input file!";
         perror(filename_.c_str());
         return -1;
@@ -114,7 +115,7 @@ int InputFileReader::IdentifyType()
     sync |= ((uint32_t)frameSize) << 16;
 
     if ((sync == 0x49c5f8ff) || (sync == 0xb63a07ff)) {
-        streamType = ETI_STREAM_TYPE_STREAMED;
+        streamType = EtiStreamType::Streamed;
         frameSize = nbFrames & 0xffff;
         if (inputfilelength_ > 0) {
             nbframes_ = inputfilelength_ / (frameSize + 2);
@@ -122,9 +123,9 @@ int InputFileReader::IdentifyType()
         else {
             nbframes_ = ~0;
         }
-        if (fseek(inputfile_, -6, SEEK_CUR) != 0) {
+        if (fseek(inputfile_.get(), -6, SEEK_CUR) != 0) {
             // if the seek fails, consume the rest of the frame
-            if (fread(discard_buffer, frameSize - 4, 1, inputfile_)
+            if (fread(discard_buffer, frameSize - 4, 1, inputfile_.get())
                     != 1) {
                 etiLog.level(error) << "Unable to read from input file!";
                 perror(filename_.c_str());
@@ -135,16 +136,16 @@ int InputFileReader::IdentifyType()
         return 0;
     }
 
-    if (fread(&sync, sizeof(sync), 1, inputfile_) != 1) {
+    if (fread(&sync, sizeof(sync), 1, inputfile_.get()) != 1) {
         etiLog.level(error) << "Unable to read nb frame in input file!";
         perror(filename_.c_str());
         return -1;
     }
     if ((sync == 0x49c5f8ff) || (sync == 0xb63a07ff)) {
-        streamType = ETI_STREAM_TYPE_FRAMED;
-        if (fseek(inputfile_, -6, SEEK_CUR) != 0) {
+        streamType = EtiStreamType::Framed;
+        if (fseek(inputfile_.get(), -6, SEEK_CUR) != 0) {
             // if the seek fails, consume the rest of the frame
-            if (fread(discard_buffer, frameSize - 4, 1, inputfile_)
+            if (fread(discard_buffer, frameSize - 4, 1, inputfile_.get())
                     != 1) {
                 etiLog.level(error) << "Unable to read from input file!";
                 perror(filename_.c_str());
@@ -160,21 +161,21 @@ int InputFileReader::IdentifyType()
     for (size_t i = 10; i < 6144 + 10; ++i) {
         sync >>= 8;
         sync &= 0xffffff;
-        if (fread((uint8_t*)&sync + 3, 1, 1, inputfile_) != 1) {
+        if (fread((uint8_t*)&sync + 3, 1, 1, inputfile_.get()) != 1) {
             etiLog.level(error) << "Unable to read from input file!";
             perror(filename_.c_str());
             return -1;
         }
         if ((sync == 0x49c5f8ff) || (sync == 0xb63a07ff)) {
-            streamType = ETI_STREAM_TYPE_RAW;
+            streamType = EtiStreamType::Raw;
             if (inputfilelength_ > 0) {
                 nbframes_ = (inputfilelength_ - i) / 6144;
             }
             else {
                 nbframes_ = ~0;
             }
-            if (fseek(inputfile_, -sizeof(sync), SEEK_CUR) != 0) {
-                if (fread(discard_buffer, 6144 - sizeof(sync), 1, inputfile_)
+            if (fseek(inputfile_.get(), -sizeof(sync), SEEK_CUR) != 0) {
+                if (fread(discard_buffer, 6144 - sizeof(sync), 1, inputfile_.get())
                         != 1) {
                     etiLog.level(error) << "Unable to read from input file!";
                     perror(filename_.c_str());
@@ -190,17 +191,17 @@ int InputFileReader::IdentifyType()
     return -1;
 }
 
-void InputFileReader::PrintInfo()
+void InputFileReader::PrintInfo() const
 {
     fprintf(stderr, "Input file format: ");
     switch (streamtype_) {
-        case ETI_STREAM_TYPE_RAW:
+        case EtiStreamType::Raw:
             fprintf(stderr, "raw");
             break;
-        case ETI_STREAM_TYPE_STREAMED:
+        case EtiStreamType::Streamed:
             fprintf(stderr, "streamed");
             break;
-        case ETI_STREAM_TYPE_FRAMED:
+        case EtiStreamType::Framed:
             fprintf(stderr, "framed");
             break;
         default:
@@ -221,15 +222,15 @@ int InputFileReader::GetNextFrame(void* buffer)
 {
     uint16_t frameSize;
 
-    if (streamtype_ == ETI_STREAM_TYPE_RAW) {
+    if (streamtype_ == EtiStreamType::Raw) {
         frameSize = 6144;
     }
     else {
-        if (fread(&frameSize, sizeof(frameSize), 1, inputfile_) != 1) {
+        if (fread(&frameSize, sizeof(frameSize), 1, inputfile_.get()) != 1) {
             etiLog.level(error) << "Reached end of file.";
             if (loop_) {
                 if (Rewind() == 0) {
-                    if (fread(&frameSize, sizeof(frameSize), 1, inputfile_) != 1) {
+                    if (fread(&frameSize, sizeof(frameSize), 1, inputfile_.get()) != 1) {
                         PDEBUG("Error after rewinding file!\n");
                         etiLog.level(error) << "Error after rewinding file!";
                         return -1;
@@ -252,15 +253,15 @@ int InputFileReader::GetNextFrame(void* buffer)
     }
 
     PDEBUG("Frame size: %u\n", frameSize);
-    size_t read_bytes = fread(buffer, 1, frameSize, inputfile_);
+    size_t read_bytes = fread(buffer, 1, frameSize, inputfile_.get());
     if (    loop_ &&
-            streamtype_ == ETI_STREAM_TYPE_RAW && //implies frameSize == 6144
-            read_bytes == 0 && feof(inputfile_)) {
+            streamtype_ == EtiStreamType::Raw && //implies frameSize == 6144
+            read_bytes == 0 && feof(inputfile_.get())) {
         // in case of an EOF from a RAW that we loop, rewind
         // otherwise, we won't tolerate it
 
         if (Rewind() == 0) {
-            read_bytes = fread(buffer, 1, frameSize, inputfile_);
+            read_bytes = fread(buffer, 1, frameSize, inputfile_.get());
         }
         else {
             PDEBUG("Impossible to rewind file!\n");
diff --git a/src/InputReader.h b/src/InputReader.h
index 7d6b373..07326cf 100644
--- a/src/InputReader.h
+++ b/src/InputReader.h
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://www.opendigitalradio.org
@@ -33,6 +33,7 @@
 
 #include <cstdio>
 #include <vector>
+#include <atomic>
 #include <memory>
 #if defined(HAVE_ZEROMQ)
 #  include "zmq.hpp"
@@ -40,47 +41,8 @@
 #endif
 #include "porting.h"
 #include "Log.h"
-#include "lib/UdpSocket.h"
-#include <sys/socket.h>
-#include <netinet/in.h>
 #include <unistd.h>
-#include <netdb.h>
-#include <arpa/inet.h>
-#define SOCKET           int
 #define INVALID_SOCKET   -1
-#define SOCKET_ERROR     -1
-
-/* Known types of input streams. Description taken from the CRC mmbTools forum.
-
-    All numbers are little-endian.
-
-    Framed format is used for file recording. It is the default format. The
-    padding can be removed from data. Format:
-        uint32_t nbFrames
-        for each frame
-          uint16_t frameSize
-          uint8_t data[frameSize]
-
-    Streamed format is used for streamed applications. As the total number of
-    frames is unknown before end of transmission, the corresponding field is
-    removed. The padding can be removed from data. Format:
-        for each frame
-          uint16_t frameSize
-          uint8_t data[frameSize]
-
-    Raw format is a bit-by-bit (but byte aligned on sync) recording of a G.703
-    data stream. The padding is always present. Format:
-        for each frame
-          uint8_t data[6144]
-
-    Please note that our raw format can also be referred to as ETI(NI, G.703) or ETI(NI).
-*/
-enum EtiStreamType {
-    ETI_STREAM_TYPE_NONE = 0,
-    ETI_STREAM_TYPE_RAW,
-    ETI_STREAM_TYPE_STREAMED,
-    ETI_STREAM_TYPE_FRAMED,
-};
 
 class InputReader
 {
@@ -91,43 +53,25 @@ class InputReader
         virtual int GetNextFrame(void* buffer) = 0;
 
         // Print some information
-        virtual void PrintInfo() = 0;
+        virtual void PrintInfo() const = 0;
 };
 
 class InputFileReader : public InputReader
 {
     public:
-        InputFileReader() :
-            streamtype_(ETI_STREAM_TYPE_NONE),
-            inputfile_(NULL) { }
-
-        ~InputFileReader()
-        {
-            if (inputfile_ != NULL) {
-                fprintf(stderr, "\nClosing input file...\n");
-
-                fclose(inputfile_);
-            }
-        }
+        InputFileReader() = default;
+        InputFileReader(const InputFileReader& other) = delete;
+        InputFileReader& operator=(const InputFileReader& other) = delete;
 
         // open file and determine stream type
         // When loop=1, GetNextFrame will never return 0
         int Open(std::string filename, bool loop);
 
         // Print information about the file opened
-        void PrintInfo();
-
+        void PrintInfo() const;
         int GetNextFrame(void* buffer);
 
-        EtiStreamType GetStreamType()
-        {
-            return streamtype_;
-        }
-
     private:
-        InputFileReader(const InputFileReader& other) = delete;
-        InputFileReader& operator=(const InputFileReader& other) = delete;
-
         int IdentifyType();
 
         // Rewind the file, and replay anew
@@ -136,19 +80,60 @@ class InputFileReader : public InputReader
 
         bool loop_; // if shall we loop the file over and over
         std::string filename_;
-        EtiStreamType streamtype_;
-        FILE* inputfile_;
 
-        size_t inputfilelength_;
-        uint64_t nbframes_; // 64-bit because 32-bit overflow is
-                            // after 2**32 * 24ms ~= 3.3 years
+        /* Known types of input streams. Description taken from the CRC
+         * mmbTools forum. All values are are little-endian.  */
+        enum class EtiStreamType {
+            /* Not yet identified */
+            None,
+
+            /* Raw format is a bit-by-bit (but byte aligned on sync) recording
+             * of a G.703 data stream. The padding is always present.
+             * The raw format can also be referred to as ETI(NI, G.703) or ETI(NI).
+             * Format:
+                 for each frame:
+                   uint8_t data[6144]
+             */
+            Raw,
+
+            /* Streamed format is used for streamed applications. As the total
+             * number of frames is unknown before end of transmission, the
+             * corresponding field is removed. The padding can be removed from
+             * data.
+             * Format:
+                 for each frame:
+                   uint16_t frameSize
+                   uint8_t data[frameSize]
+             */
+            Streamed,
+
+            /* Framed format is used for file recording. It is the default format.
+             * The padding can be removed from data.
+             * Format:
+                 uint32_t nbFrames
+                 for each frame:
+                   uint16_t frameSize
+                   uint8_t data[frameSize]
+             */
+            Framed,
+        };
+
+        EtiStreamType streamtype_ = EtiStreamType::None;
+        struct FILEDeleter{ void operator()(FILE* fd){ if(fd) fclose(fd);}};
+        std::unique_ptr<FILE, FILEDeleter> inputfile_;
+
+        size_t inputfilelength_ = 0;
+        uint64_t nbframes_ = 0; // 64-bit because 32-bit overflow is
+        // after 2**32 * 24ms ~= 3.3 years
 };
 
 class InputTcpReader : public InputReader
 {
     public:
         InputTcpReader();
-        ~InputTcpReader();
+        InputTcpReader(const InputTcpReader& other) = delete;
+        InputTcpReader& operator=(const InputTcpReader& other) = delete;
+        virtual ~InputTcpReader();
 
         // Endpoint is either host:port or tcp://host:port
         void Open(const std::string& endpoint);
@@ -159,89 +144,54 @@ class InputTcpReader : public InputReader
         virtual int GetNextFrame(void* buffer);
 
         // Print some information
-        virtual void PrintInfo();
+        virtual void PrintInfo() const;
 
     private:
-        InputTcpReader(const InputTcpReader& other) = delete;
-        InputTcpReader& operator=(const InputTcpReader& other) = delete;
-        SOCKET m_sock;
+        int m_sock = INVALID_SOCKET;
         std::string m_uri;
 };
 
 struct zmq_input_overflow : public std::exception
 {
-  const char* what () const throw ()
-  {
-    return "InputZMQ buffer overflow";
-  }
+    const char* what () const throw ()
+    {
+        return "InputZMQ buffer overflow";
+    }
 };
 
 #if defined(HAVE_ZEROMQ)
 /* A ZeroMQ input. See www.zeromq.org for more info */
 
-struct InputZeroMQThreadData
-{
-    ThreadsafeQueue<std::shared_ptr<std::vector<uint8_t> > > *in_messages;
-    std::string uri;
-    size_t max_queued_frames;
-};
-
-class InputZeroMQWorker
+class InputZeroMQReader : public InputReader
 {
     public:
-        InputZeroMQWorker() :
-            running(false),
-            zmqcontext(1),
-            m_to_drop(0) { }
+        InputZeroMQReader() = default;
+        InputZeroMQReader(const InputZeroMQReader& other) = delete;
+        InputZeroMQReader& operator=(const InputZeroMQReader& other) = delete;
+        ~InputZeroMQReader();
 
-        void Start(struct InputZeroMQThreadData* workerdata);
-        void Stop();
+        int Open(const std::string& uri, size_t max_queued_frames);
+        int GetNextFrame(void* buffer);
+        void PrintInfo() const;
 
-        bool is_running(void) { return running; }
     private:
-        bool running;
+        std::atomic<bool> m_running = ATOMIC_VAR_INIT(false);
+        std::string m_uri;
+        size_t m_max_queued_frames = 0;
+        ThreadsafeQueue<std::shared_ptr<std::vector<uint8_t> > > m_in_messages;
 
-        void RecvProcess(struct InputZeroMQThreadData* workerdata);
+        void RecvProcess(void);
 
-        zmq::context_t zmqcontext; // is thread-safe
-        boost::thread recv_thread;
+        zmq::context_t m_zmqcontext; // is thread-safe
+        boost::thread m_recv_thread;
 
         /* We must be careful to keep frame phase consistent. If we
          * drop a single ETI frame, we will break the transmission
          * frame vs. ETI frame phase.
          *
-         * Here we keep track of how many ETI frames we must drop
+         * Here we keep track of how many ETI frames we must drop.
          */
-        int m_to_drop;
-};
-
-class InputZeroMQReader : public InputReader
-{
-    public:
-        InputZeroMQReader()
-        {
-            workerdata_.in_messages = &in_messages_;
-        }
-
-        ~InputZeroMQReader()
-        {
-            worker_.Stop();
-        }
-
-        int Open(const std::string& uri, size_t max_queued_frames);
-
-        int GetNextFrame(void* buffer);
-
-        void PrintInfo();
-
-    private:
-        InputZeroMQReader(const InputZeroMQReader& other) = delete;
-        InputZeroMQReader& operator=(const InputZeroMQReader& other) = delete;
-        std::string uri_;
-
-        InputZeroMQWorker worker_;
-        ThreadsafeQueue<std::shared_ptr<std::vector<uint8_t> > > in_messages_;
-        struct InputZeroMQThreadData workerdata_;
+        int m_to_drop = 0;
 };
 
 #endif
diff --git a/src/InputTcpReader.cpp b/src/InputTcpReader.cpp
index 94ec0ad..9a93ad1 100644
--- a/src/InputTcpReader.cpp
+++ b/src/InputTcpReader.cpp
@@ -32,9 +32,12 @@
 #include "InputReader.h"
 #include "PcDebug.h"
 #include "Utils.h"
-#include <sys/socket.h>
 #include <unistd.h>
 #include <errno.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <arpa/inet.h>
 
 InputTcpReader::InputTcpReader()
 {
@@ -126,7 +129,7 @@ int InputTcpReader::GetNextFrame(void* buffer)
     return r;
 }
 
-void InputTcpReader::PrintInfo()
+void InputTcpReader::PrintInfo() const
 {
     fprintf(stderr, "Input TCP:\n");
     fprintf(stderr, "  Receiving from %s\n\n", m_uri.c_str());
diff --git a/src/InputZeroMQReader.cpp b/src/InputZeroMQReader.cpp
index 783f0f5..f6a816a 100644
--- a/src/InputZeroMQReader.cpp
+++ b/src/InputZeroMQReader.cpp
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -68,29 +68,35 @@ struct zmq_dab_message_t
 #define ZMQ_DAB_MESSAGE_T_HEADERSIZE \
     (sizeof(uint32_t) + NUM_FRAMES_PER_ZMQ_MESSAGE*sizeof(uint16_t))
 
+InputZeroMQReader::~InputZeroMQReader()
+{
+    m_running = false;
+    m_zmqcontext.close();
+    if (m_recv_thread.joinable()) {
+            m_recv_thread.join();
+    }
+}
+
 int InputZeroMQReader::Open(const string& uri, size_t max_queued_frames)
 {
     // The URL might start with zmq+tcp://
     if (uri.substr(0, 4) == "zmq+") {
-        uri_ = uri.substr(4);
+        m_uri = uri.substr(4);
     }
     else {
-        uri_ = uri;
+        m_uri = uri;
     }
 
-    workerdata_.uri = uri_;
-    workerdata_.max_queued_frames = max_queued_frames;
-    // launch receiver thread
-    worker_.Start(&workerdata_);
+    m_max_queued_frames = max_queued_frames;
+
+    m_recv_thread = boost::thread(&InputZeroMQReader::RecvProcess, this);
 
     return 0;
 }
 
 int InputZeroMQReader::GetNextFrame(void* buffer)
 {
-    const size_t framesize = 6144;
-
-    if (not worker_.is_running()) {
+    if (not m_running) {
         return 0;
     }
 
@@ -100,77 +106,100 @@ int InputZeroMQReader::GetNextFrame(void* buffer)
      * (4 ETI frames in TM1) and we should make sure that
      * we can serve the data required for a full transmission frame.
      */
-    if (in_messages_.size() < 4) {
+    if (m_in_messages.size() < 4) {
         const size_t prebuffering = 10;
         etiLog.log(trace, "ZMQ,wait1");
-        in_messages_.wait_and_pop(incoming, prebuffering);
+        m_in_messages.wait_and_pop(incoming, prebuffering);
     }
     else {
         etiLog.log(trace, "ZMQ,wait2");
-        in_messages_.wait_and_pop(incoming);
+        m_in_messages.wait_and_pop(incoming);
     }
     etiLog.log(trace, "ZMQ,pop");
 
-    if (not worker_.is_running()) {
+    if (not m_running) {
         throw zmq_input_overflow();
     }
 
-    memcpy(buffer, &incoming->front(), framesize);
+
+    const size_t framesize = 6144;
+    if (incoming->empty()) {
+        return 0;
+    }
+    else if (incoming->size() == framesize) {
+        memcpy(buffer, &incoming->front(), framesize);
+    }
+    else {
+        throw logic_error("ZMQ ETI not 6144");
+    }
 
     return framesize;
 }
 
-void InputZeroMQReader::PrintInfo()
+void InputZeroMQReader::PrintInfo() const
 {
     fprintf(stderr, "Input ZeroMQ:\n");
-    fprintf(stderr, "  Receiving from %s\n\n", uri_.c_str());
+    fprintf(stderr, "  Receiving from %s\n\n", m_uri.c_str());
 }
 
-// ------------- Worker functions
-
-void InputZeroMQWorker::RecvProcess(struct InputZeroMQThreadData* workerdata)
+void InputZeroMQReader::RecvProcess()
 {
     set_thread_name("zmqinput");
-    size_t queue_size = 0;
+    m_running = true;
 
+    size_t queue_size = 0;
     bool buffer_full = false;
 
-    zmq::socket_t subscriber(zmqcontext, ZMQ_SUB);
+    zmq::socket_t subscriber(m_zmqcontext, ZMQ_SUB);
     // zmq sockets are not thread safe. That's why
     // we create it here, and not at object creation.
 
     bool success = true;
 
     try {
-        subscriber.connect(workerdata->uri.c_str());
+        subscriber.connect(m_uri.c_str());
     }
     catch (zmq::error_t& err) {
-        etiLog.level(error) << "Failed to connect ZeroMQ socket to '" << workerdata->uri << "': '" << err.what() << "'";
+        etiLog.level(error) << "Failed to connect ZeroMQ socket to '" <<
+            m_uri << "': '" << err.what() << "'";
         success = false;
     }
 
     if (success) try {
-        subscriber.setsockopt(ZMQ_SUBSCRIBE, NULL, 0); // subscribe to all messages
+        // subscribe to all messages
+        subscriber.setsockopt(ZMQ_SUBSCRIBE, NULL, 0);
     }
     catch (zmq::error_t& err) {
-        etiLog.level(error) << "Failed to subscribe ZeroMQ socket to messages: '" << err.what() << "'";
+        etiLog.level(error) << "Failed to subscribe ZeroMQ socket to messages: '" <<
+            err.what() << "'";
         success = false;
     }
 
     if (success) try {
-        while (running)
-        {
+        while (m_running) {
             zmq::message_t incoming;
+            zmq::pollitem_t items[1];
+            items[0].socket = subscriber;
+            items[0].events = ZMQ_POLLIN;
+            const int zmq_timeout_ms = 100;
+            const int num_events = zmq::poll(items, 1, zmq_timeout_ms);
+            if (num_events == 0) {
+                // timeout is signalled by an empty buffer
+                auto buf = make_shared<vector<uint8_t> >();
+                m_in_messages.push(buf);
+                continue;
+            }
+
             subscriber.recv(&incoming);
 
             if (m_to_drop) {
-                queue_size = workerdata->in_messages->size();
+                queue_size = m_in_messages.size();
                 if (queue_size > 4) {
-                    workerdata->in_messages->notify();
+                    m_in_messages.notify();
                 }
                 m_to_drop--;
             }
-            else if (queue_size < workerdata->max_queued_frames) {
+            else if (queue_size < m_max_queued_frames) {
                 if (buffer_full) {
                     etiLog.level(info) << "ZeroMQ buffer recovered: " <<
                         queue_size << " elements";
@@ -214,14 +243,14 @@ void InputZeroMQWorker::RecvProcess(struct InputZeroMQThreadData* workerdata)
 
                             offset += framesize;
 
-                            queue_size = workerdata->in_messages->push(buf);
+                            queue_size = m_in_messages.push(buf);
                             etiLog.log(trace, "ZMQ,push %zu", queue_size);
                         }
                     }
                 }
             }
             else {
-                workerdata->in_messages->notify();
+                m_in_messages.notify();
 
                 if (!buffer_full) {
                     etiLog.level(warn) << "ZeroMQ buffer overfull !";
@@ -230,7 +259,7 @@ void InputZeroMQWorker::RecvProcess(struct InputZeroMQThreadData* workerdata)
                     throw runtime_error("ZMQ input full");
                 }
 
-                queue_size = workerdata->in_messages->size();
+                queue_size = m_in_messages.size();
 
                 /* Drop three more incoming ETI frames before
                  * we start accepting them again, to guarantee
@@ -256,21 +285,8 @@ void InputZeroMQWorker::RecvProcess(struct InputZeroMQThreadData* workerdata)
 
     subscriber.close();
 
-    running = false;
-    workerdata->in_messages->notify();
-}
-
-void InputZeroMQWorker::Start(struct InputZeroMQThreadData* workerdata)
-{
-    running = true;
-    recv_thread = boost::thread(&InputZeroMQWorker::RecvProcess, this, workerdata);
-}
-
-void InputZeroMQWorker::Stop()
-{
-    running = false;
-    zmqcontext.close();
-    recv_thread.join();
+    m_running = false;
+    m_in_messages.notify();
 }
 
 #endif
diff --git a/src/Log.cpp b/src/Log.cpp
index 0792fcf..f2219eb 100644
--- a/src/Log.cpp
+++ b/src/Log.cpp
@@ -109,6 +109,17 @@ LogLine Logger::level(log_level_t level)
     return LogLine(this, level);
 }
 
+LogToFile::LogToFile(const std::string& filename) : name("FILE")
+{
+    FILE* fd = fopen(filename.c_str(), "a");
+    if (fd == nullptr) {
+        fprintf(stderr, "Cannot open log file !");
+        throw std::runtime_error("Cannot open log file !");
+    }
+
+    log_file.reset(fd);
+}
+
 void LogToFile::log(log_level_t level, const std::string& message)
 {
     if (level != log_level_t::trace) {
@@ -116,9 +127,9 @@ void LogToFile::log(log_level_t level, const std::string& message)
             "DEBUG", "INFO", "WARN", "ERROR", "ALERT", "EMERG"};
 
         // fprintf is thread-safe
-        fprintf(log_file, SYSLOG_IDENT ": %s: %s\n",
+        fprintf(log_file.get(), SYSLOG_IDENT ": %s: %s\n",
                 log_level_text[(size_t)level], message.c_str());
-        fflush(log_file);
+        fflush(log_file.get());
     }
 }
 
@@ -142,31 +153,33 @@ void LogToSyslog::log(log_level_t level, const std::string& message)
     }
 }
 
-LogTracer::LogTracer(const string& trace_filename)
+LogTracer::LogTracer(const string& trace_filename) : name("TRACE")
 {
-    name = "TRACE";
     etiLog.level(info) << "Setting up TRACE to " << trace_filename;
 
-    m_trace_file = fopen(trace_filename.c_str(), "a");
-    if (m_trace_file == NULL) {
+    FILE* fd = fopen(trace_filename.c_str(), "a");
+    if (fd == nullptr) {
         fprintf(stderr, "Cannot open trace file !");
         throw std::runtime_error("Cannot open trace file !");
     }
+    m_trace_file.reset(fd);
 
-    auto now = chrono::steady_clock::now().time_since_epoch();
-    m_trace_micros_startup =
-        chrono::duration_cast<chrono::microseconds>(now).count();
+    using namespace std::chrono;
+    auto now = steady_clock::now().time_since_epoch();
+    m_trace_micros_startup = duration_cast<microseconds>(now).count();
 
-    fprintf(m_trace_file, "0,TRACER,startup at %ld\n", m_trace_micros_startup);
+    fprintf(m_trace_file.get(),
+            "0,TRACER,startup at %ld\n", m_trace_micros_startup);
 }
 
 void LogTracer::log(log_level_t level, const std::string& message)
 {
     if (level == log_level_t::trace) {
-        const auto now = chrono::steady_clock::now().time_since_epoch();
-        const auto micros = chrono::duration_cast<chrono::microseconds>(now).count();
+        using namespace std::chrono;
+        const auto now = steady_clock::now().time_since_epoch();
+        const auto micros = duration_cast<microseconds>(now).count();
 
-        fprintf(m_trace_file, "%ld,%s\n",
+        fprintf(m_trace_file.get(), "%ld,%s\n",
                 micros - m_trace_micros_startup,
                 message.c_str());
     }
diff --git a/src/Log.h b/src/Log.h
index ae252a6..0e09bc9 100644
--- a/src/Log.h
+++ b/src/Log.h
@@ -57,7 +57,7 @@ static const std::string levels_as_str[] =
 class LogBackend {
     public:
         virtual void log(log_level_t level, const std::string& message) = 0;
-        virtual std::string get_name() = 0;
+        virtual std::string get_name() const = 0;
 };
 
 /** A Logging backend for Syslog */
@@ -73,7 +73,7 @@ class LogToSyslog : public LogBackend {
 
         void log(log_level_t level, const std::string& message);
 
-        std::string get_name() { return name; }
+        std::string get_name() const { return name; }
 
     private:
         const std::string name;
@@ -84,27 +84,15 @@ class LogToSyslog : public LogBackend {
 
 class LogToFile : public LogBackend {
     public:
-        LogToFile(const std::string& filename) : name("FILE") {
-            log_file = fopen(filename.c_str(), "a");
-            if (log_file == NULL) {
-                fprintf(stderr, "Cannot open log file !");
-                throw std::runtime_error("Cannot open log file !");
-            }
-        }
-
-        ~LogToFile() {
-            if (log_file != NULL) {
-                fclose(log_file);
-            }
-        }
-
+        LogToFile(const std::string& filename);
         void log(log_level_t level, const std::string& message);
-
-        std::string get_name() { return name; }
+        std::string get_name() const { return name; }
 
     private:
         const std::string name;
-        FILE* log_file;
+
+        struct FILEDeleter{ void operator()(FILE* fd){ if(fd) fclose(fd);}};
+        std::unique_ptr<FILE, FILEDeleter> log_file;
 
         LogToFile(const LogToFile& other) = delete;
         const LogToFile& operator=(const LogToFile& other) = delete;
@@ -113,19 +101,14 @@ class LogToFile : public LogBackend {
 class LogTracer : public LogBackend {
     public:
         LogTracer(const std::string& filename);
-
-        ~LogTracer() {
-            if (m_trace_file != NULL) {
-                fclose(m_trace_file);
-            }
-        }
-
         void log(log_level_t level, const std::string& message);
-        std::string get_name() { return name; }
+        std::string get_name() const { return name; }
     private:
         std::string name;
-        uint64_t m_trace_micros_startup;
-        FILE* m_trace_file;
+        uint64_t m_trace_micros_startup = 0;
+
+        struct FILEDeleter{ void operator()(FILE* fd){ if(fd) fclose(fd);}};
+        std::unique_ptr<FILE, FILEDeleter> m_trace_file;
 
         LogTracer(const LogTracer& other) = delete;
         const LogTracer& operator=(const LogTracer& other) = delete;
diff --git a/src/MemlessPoly.cpp b/src/MemlessPoly.cpp
index ae097c9..5d1c02d 100644
--- a/src/MemlessPoly.cpp
+++ b/src/MemlessPoly.cpp
@@ -99,6 +99,11 @@ MemlessPoly::MemlessPoly(const std::string& coefs_file, unsigned int num_threads
     start_pipeline_thread();
 }
 
+MemlessPoly::~MemlessPoly()
+{
+    stop_pipeline_thread();
+}
+
 void MemlessPoly::load_coefficients(const std::string &coefFile)
 {
     std::ifstream coef_fstream(coefFile.c_str());
diff --git a/src/MemlessPoly.h b/src/MemlessPoly.h
index 612934f..4c67d46 100644
--- a/src/MemlessPoly.h
+++ b/src/MemlessPoly.h
@@ -59,6 +59,9 @@ class MemlessPoly : public PipelinedModCodec, public RemoteControllable
 {
 public:
     MemlessPoly(const std::string& coefs_file, unsigned int num_threads);
+    MemlessPoly(const MemlessPoly& other) = delete;
+    MemlessPoly& operator=(const MemlessPoly& other) = delete;
+    virtual ~MemlessPoly();
 
     virtual const char* name() { return "MemlessPoly"; }
 
diff --git a/src/ModPlugin.cpp b/src/ModPlugin.cpp
index c39d883..d567a90 100644
--- a/src/ModPlugin.cpp
+++ b/src/ModPlugin.cpp
@@ -72,17 +72,7 @@ int ModOutput::process(
     return process(dataIn[0]);
 }
 
-PipelinedModCodec::PipelinedModCodec() :
-    ModCodec(),
-    m_number_of_runs(0),
-    m_input_queue(),
-    m_output_queue(),
-    m_running(false),
-    m_thread()
-{
-}
-
-PipelinedModCodec::~PipelinedModCodec()
+void PipelinedModCodec::stop_pipeline_thread()
 {
     m_input_queue.push({});
     if (m_thread.joinable()) {
@@ -107,7 +97,7 @@ int PipelinedModCodec::process(Buffer* dataIn, Buffer* dataOut)
 
     m_input_queue.push(inbuffer);
 
-    if (m_number_of_runs > 0) {
+    if (m_ready_to_output_data) {
         std::shared_ptr<Buffer> outbuffer;
         m_output_queue.wait_and_pop(outbuffer);
 
@@ -116,13 +106,26 @@ int PipelinedModCodec::process(Buffer* dataIn, Buffer* dataOut)
     else {
         dataOut->setLength(dataIn->getLength());
         memset(dataOut->getData(), 0, dataOut->getLength());
-        m_number_of_runs++;
+        m_ready_to_output_data = true;
     }
 
     return dataOut->getLength();
 
 }
 
+meta_vec_t PipelinedModCodec::process_metadata(const meta_vec_t& metadataIn)
+{
+    m_metadata_fifo.push_back(metadataIn);
+    if (m_metadata_fifo.size() == 2) {
+        auto r = std::move(m_metadata_fifo.front());
+        m_metadata_fifo.pop_front();
+        return r;
+    }
+    else {
+        return {};
+    }
+}
+
 void PipelinedModCodec::process_thread()
 {
     set_thread_name(name());
diff --git a/src/ModPlugin.h b/src/ModPlugin.h
index d3aa780..e9cfa21 100644
--- a/src/ModPlugin.h
+++ b/src/ModPlugin.h
@@ -30,16 +30,34 @@
 #   include <config.h>
 #endif
 
-
 #include "Buffer.h"
 #include "ThreadsafeQueue.h"
-
-#include <sys/types.h>
+#include <cstddef>
 #include <vector>
 #include <memory>
 #include <thread>
 #include <atomic>
 
+// All flowgraph elements derive from ModPlugin, or a variant of it.
+// Some ModPlugins also support handling metadata.
+
+struct frame_timestamp;
+struct flowgraph_metadata {
+    std::shared_ptr<struct frame_timestamp> ts;
+};
+
+using meta_vec_t = std::vector<flowgraph_metadata>;
+
+/* ModPlugins that support metadata derive from ModMetadata */
+class ModMetadata {
+    public:
+        // Receives metadata from all inputs, and process them, and output
+        // a sequence of metadata.
+        virtual meta_vec_t process_metadata(const meta_vec_t& metadataIn) = 0;
+};
+
+
+/* Abstract base class for all flowgraph elements */
 class ModPlugin
 {
 public:
@@ -47,6 +65,7 @@ public:
             std::vector<Buffer*> dataIn,
             std::vector<Buffer*> dataOut) = 0;
     virtual const char* name() = 0;
+    virtual ~ModPlugin() = default;
 };
 
 /* Inputs are sources, the output buffers without reading any */
@@ -69,32 +88,38 @@ public:
     virtual int process(Buffer* const dataIn, Buffer* dataOut) = 0;
 };
 
-class PipelinedModCodec : public ModCodec
+/* Pipelined ModCodecs run their processing in a separate thread, and
+ * have a one-call-to-process() latency. Because of this latency, they
+ * must also handle the metadata
+ */
+class PipelinedModCodec : public ModCodec, public ModMetadata
 {
 public:
-    PipelinedModCodec();
-    PipelinedModCodec(const PipelinedModCodec&) = delete;
-    PipelinedModCodec& operator=(const PipelinedModCodec&) = delete;
-    PipelinedModCodec(PipelinedModCodec&&) = delete;
-    PipelinedModCodec& operator=(PipelinedModCodec&&) = delete;
-    ~PipelinedModCodec();
-
     virtual int process(Buffer* const dataIn, Buffer* dataOut) final;
     virtual const char* name() = 0;
 
+    virtual meta_vec_t process_metadata(const meta_vec_t& metadataIn) final;
+
 protected:
     // Once the instance implementing PipelinedModCodec has been constructed,
     // it must call start_pipeline_thread()
     void start_pipeline_thread(void);
+    // To avoid race conditions on teardown, plugins must call
+    // stop_pipeline_thread in their destructor.
+    void stop_pipeline_thread(void);
+
+    // The real processing must be implemented in internal_process
     virtual int internal_process(Buffer* const dataIn, Buffer* dataOut) = 0;
 
 private:
-    size_t m_number_of_runs;
+    bool m_ready_to_output_data = false;
 
     ThreadsafeQueue<std::shared_ptr<Buffer> > m_input_queue;
     ThreadsafeQueue<std::shared_ptr<Buffer> > m_output_queue;
 
-    std::atomic<bool> m_running;
+    std::deque<meta_vec_t> m_metadata_fifo;
+
+    std::atomic<bool> m_running = ATOMIC_VAR_INIT(false);
     std::thread m_thread;
     void process_thread(void);
 };
@@ -119,3 +144,4 @@ public:
             std::vector<Buffer*> dataOut);
     virtual int process(Buffer* dataIn) = 0;
 };
+
diff --git a/src/OfdmGenerator.cpp b/src/OfdmGenerator.cpp
index b00d66b..57e0e0e 100644
--- a/src/OfdmGenerator.cpp
+++ b/src/OfdmGenerator.cpp
@@ -139,6 +139,14 @@ OfdmGenerator::~OfdmGenerator()
         fftwf_destroy_plan(myFftPlan);
     }
 
+    if (myCfrPostClip) {
+        fftwf_free(myCfrPostClip);
+    }
+
+    if (myCfrPostFft) {
+        fftwf_free(myCfrPostFft);
+    }
+
     if (myCfrFft) {
         fftwf_destroy_plan(myCfrFft);
     }
diff --git a/src/OutputFile.cpp b/src/OutputFile.cpp
index 23d5523..46a9ec9 100644
--- a/src/OutputFile.cpp
+++ b/src/OutputFile.cpp
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -26,47 +26,78 @@
 
 #include "OutputFile.h"
 #include "PcDebug.h"
+#include "Log.h"
+#include "TimestampDecoder.h"
 
 #include <string>
 #include <assert.h>
 #include <stdexcept>
 
 
-OutputFile::OutputFile(std::string filename) :
-    ModOutput(),
+using namespace std;
+
+OutputFile::OutputFile(const std::string& filename, bool show_metadata) :
+    ModOutput(), ModMetadata(),
+    myShowMetadata(show_metadata),
     myFilename(filename)
 {
     PDEBUG("OutputFile::OutputFile(filename: %s) @ %p\n",
             filename.c_str(), this);
 
-    myFile = fopen(filename.c_str(), "w");
-    if (myFile == NULL) {
+    FILE* fd = fopen(filename.c_str(), "w");
+    if (fd == nullptr) {
         perror(filename.c_str());
         throw std::runtime_error(
                 "OutputFile::OutputFile() unable to open file!");
     }
-}
-
-
-OutputFile::~OutputFile()
-{
-    PDEBUG("OutputFile::~OutputFile() @ %p\n", this);
-
-    if (myFile != NULL) {
-        fclose(myFile);
-    }
+    myFile.reset(fd);
 }
 
 
 int OutputFile::process(Buffer* dataIn)
 {
     PDEBUG("OutputFile::process(%p)\n", dataIn);
-    assert(dataIn != NULL);
+    assert(dataIn != nullptr);
 
-    if (fwrite(dataIn->getData(), dataIn->getLength(), 1, myFile) == 0) {
+    if (fwrite(dataIn->getData(), dataIn->getLength(), 1, myFile.get()) == 0) {
         throw std::runtime_error(
                 "OutputFile::process() unable to write to file!");
     }
 
     return dataIn->getLength();
 }
+
+meta_vec_t OutputFile::process_metadata(const meta_vec_t& metadataIn)
+{
+    if (myShowMetadata) {
+        stringstream ss;
+
+        for (const auto& md : metadataIn) {
+            if (md.ts) {
+                ss << " FCT=" << md.ts->fct <<
+                    " FP=" << (int)md.ts->fp;
+                if (md.ts->timestamp_valid) {
+                    ss << " TS=" << md.ts->timestamp_sec << " + " <<
+                        std::fixed
+                        << (double)md.ts->timestamp_pps / 163840000.0 << ";";
+                }
+                else {
+                    ss << " TS invalid;";
+                }
+            }
+            else {
+                ss << " void, ";
+            }
+        }
+
+        if (metadataIn.empty()) {
+            etiLog.level(debug) << "Output File got no mdIn";
+        }
+        else {
+            etiLog.level(debug) << "Output File got metadata: " << ss.str();
+        }
+
+    }
+    return {};
+}
+
diff --git a/src/OutputFile.h b/src/OutputFile.h
index 7121ef3..745e672 100644
--- a/src/OutputFile.h
+++ b/src/OutputFile.h
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -32,23 +32,29 @@
 
 
 #include "ModPlugin.h"
+#include "EtiReader.h"
 
 #include <string>
 #include <stdio.h>
 #include <sys/types.h>
+#include <memory>
 
-
-class OutputFile : public ModOutput
+class OutputFile : public ModOutput, public ModMetadata
 {
 public:
-    OutputFile(std::string filename);
-    virtual ~OutputFile();
+    OutputFile(const std::string& filename, bool show_metadata);
+
+    virtual int process(Buffer* dataIn) override;
+    const char* name() override { return "OutputFile"; }
 
-    virtual int process(Buffer* dataIn);
-    const char* name() { return "OutputFile"; }
+    virtual meta_vec_t process_metadata(
+            const meta_vec_t& metadataIn) override;
 
 protected:
+    bool myShowMetadata = false;
     std::string myFilename;
-    FILE* myFile;
+
+    struct FILEDeleter{ void operator()(FILE* fd){ if (fd) fclose(fd); }};
+    std::unique_ptr<FILE, FILEDeleter> myFile;
 };
 
diff --git a/src/OutputMemory.cpp b/src/OutputMemory.cpp
index 6e2fd49..5f24095 100644
--- a/src/OutputMemory.cpp
+++ b/src/OutputMemory.cpp
@@ -2,7 +2,7 @@
    Copyright (C) 2007, 2008, 2009, 2010, 2011 Her Majesty the Queen in
    Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -26,6 +26,7 @@
 
 #include "OutputMemory.h"
 #include "PcDebug.h"
+#include "Log.h"
 
 #include <stdexcept>
 #include <string.h>
@@ -94,3 +95,14 @@ int OutputMemory::process(Buffer* dataIn)
     return myDataOut->getLength();
 }
 
+meta_vec_t OutputMemory::process_metadata(const meta_vec_t& metadataIn)
+{
+    myMetadata = metadataIn;
+    return {};
+}
+
+meta_vec_t OutputMemory::get_latest_metadata()
+{
+    return myMetadata;
+}
+
diff --git a/src/OutputMemory.h b/src/OutputMemory.h
index 715cb2d..f0a5fbb 100644
--- a/src/OutputMemory.h
+++ b/src/OutputMemory.h
@@ -2,7 +2,7 @@
    Copyright (C) 2007, 2008, 2009, 2010, 2011 Her Majesty the Queen in
    Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2016
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -46,18 +46,26 @@
 #include "ModPlugin.h"
 
 
-class OutputMemory : public ModOutput
+class OutputMemory : public ModOutput, public ModMetadata
 {
 public:
     OutputMemory(Buffer* dataOut);
     virtual ~OutputMemory();
-    virtual int process(Buffer* dataIn);
-    const char* name() { return "OutputMemory"; }
+    OutputMemory(OutputMemory& other) = delete;
+    OutputMemory& operator=(OutputMemory& other) = delete;
+
+    virtual int process(Buffer* dataIn) override;
+    const char* name() override { return "OutputMemory"; }
+    virtual meta_vec_t process_metadata(
+            const meta_vec_t& metadataIn) override;
+
+    meta_vec_t get_latest_metadata(void);
 
     void setOutput(Buffer* dataOut);
 
 protected:
     Buffer* myDataOut;
+    meta_vec_t myMetadata;
 
 #if OUTPUT_MEM_HISTOGRAM
     // keep track of max value
diff --git a/src/OutputSoapy.cpp b/src/OutputSoapy.cpp
deleted file mode 100644
index 699501c..0000000
--- a/src/OutputSoapy.cpp
+++ /dev/null
@@ -1,287 +0,0 @@
-/*
-   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
-   Queen in Right of Canada (Communications Research Center Canada)
-
-   Copyright (C) 2017
-   Matthias P. Braendli, matthias.braendli@mpb.li
-
-    http://opendigitalradio.org
-
-DESCRIPTION:
-   It is an output driver using the SoapySDR library that can output to
-   many devices.
-*/
-
-/*
-   This file is part of ODR-DabMod.
-
-   ODR-DabMod is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as
-   published by the Free Software Foundation, either version 3 of the
-   License, or (at your option) any later version.
-
-   ODR-DabMod is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include "OutputSoapy.h"
-#ifdef HAVE_SOAPYSDR
-
-#include <SoapySDR/Errors.hpp>
-#include <deque>
-#include <chrono>
-
-#include "Log.h"
-#include "Utils.h"
-
-#include <stdio.h>
-
-static const size_t FRAMES_MAX_SIZE = 2;
-
-
-using namespace std;
-
-
-
-OutputSoapy::OutputSoapy(OutputSoapyConfig& config) :
-    ModOutput(),
-    RemoteControllable("soapy"),
-    m_conf(config),
-    m_device(nullptr)
-{
-    RC_ADD_PARAMETER(txgain, "SoapySDR analog daughterboard TX gain");
-    RC_ADD_PARAMETER(freq,   "SoapySDR transmission frequency");
-    RC_ADD_PARAMETER(overflows, "SoapySDR overflow count [r/o]");
-    RC_ADD_PARAMETER(underflows, "SoapySDR underflow count [r/o]");
-
-    etiLog.level(info) <<
-        "OutputSoapy:Creating the device with: " <<
-        config.device;
-    try
-    {
-        m_device = SoapySDR::Device::make(config.device);
-        stringstream ss;
-        ss << "SoapySDR driver=" << m_device->getDriverKey();
-        ss << " hardware=" << m_device->getHardwareKey();
-        for (const auto &it : m_device->getHardwareInfo())
-        {
-            ss << "  " << it.first << "=" << it.second;
-        }
-    }
-    catch (const std::exception &ex)
-    {
-        etiLog.level(error) << "Error making SoapySDR device: " <<
-            ex.what();
-        throw std::runtime_error("Cannot create SoapySDR output");
-    }
-
-    m_device->setMasterClockRate(config.masterClockRate);
-    etiLog.level(info) << "SoapySDR master clock rate set to " <<
-        m_device->getMasterClockRate()/1000.0 << " kHz";
-
-    m_device->setSampleRate(SOAPY_SDR_TX, 0, m_conf.sampleRate);
-    etiLog.level(info) << "OutputSoapySDR:Actual TX rate: " <<
-        m_device->getSampleRate(SOAPY_SDR_TX, 0) / 1000.0 <<
-        " ksps.";
-
-    m_device->setFrequency(SOAPY_SDR_TX, 0, m_conf.frequency);
-    m_conf.frequency = m_device->getFrequency(SOAPY_SDR_TX, 0);
-    etiLog.level(info) << "OutputSoapySDR:Actual frequency: " <<
-        m_conf.frequency / 1000.0 <<
-        " kHz.";
-
-    m_device->setGain(SOAPY_SDR_TX, 0, m_conf.txgain);
-    etiLog.level(info) << "OutputSoapySDR:Actual tx gain: " <<
-        m_device->getGain(SOAPY_SDR_TX, 0);
-
-}
-
-OutputSoapy::~OutputSoapy()
-{
-    m_worker.stop();
-    if (m_device != nullptr) {
-        SoapySDR::Device::unmake(m_device);
-    }
-}
-
-void SoapyWorker::stop()
-{
-    running = false;
-    queue.push({});
-    if (m_thread.joinable()) {
-        m_thread.join();
-    }
-}
-
-void SoapyWorker::start(SoapySDR::Device *device)
-{
-    m_device = device;
-    underflows = 0;
-    overflows = 0;
-    running = true;
-    m_thread = std::thread(&SoapyWorker::process_start, this);
-}
-
-void SoapyWorker::process_start()
-{
-    // Set thread priority to realtime
-    if (int ret = set_realtime_prio(1)) {
-        etiLog.level(error) << "Could not set priority for SoapySDR worker:" << ret;
-    }
-
-    set_thread_name("soapyworker");
-
-    std::vector<size_t> channels;
-    channels.push_back(0);
-    auto stream = m_device->setupStream(SOAPY_SDR_TX, "CF32", channels);
-    m_device->activateStream(stream);
-    process(stream);
-    m_device->closeStream(stream);
-    running = false;
-    etiLog.level(warn) << "SoapySDR worker terminated";
-}
-
-void SoapyWorker::process(SoapySDR::Stream *stream)
-{
-    while (running) {
-        struct SoapyWorkerFrameData frame;
-        queue.wait_and_pop(frame);
-
-        // The frame buffer contains bytes representing FC32 samples
-        const complexf *buf = reinterpret_cast<complexf*>(frame.buf.data());
-        const size_t numSamples = frame.buf.size() / sizeof(complexf);
-        if ((frame.buf.size() % sizeof(complexf)) != 0) {
-            throw std::runtime_error("OutputSoapy: invalid buffer size");
-        }
-
-        // Stream MTU is in samples, not bytes.
-        const size_t mtu = m_device->getStreamMTU(stream);
-
-        size_t num_acc_samps = 0;
-        while (running && (num_acc_samps < numSamples)) {
-            const void *buffs[1];
-            buffs[0] = buf + num_acc_samps;
-
-            const size_t samps_to_send = std::min(numSamples - num_acc_samps, mtu);
-
-            int flags = 0;
-
-            auto ret = m_device->writeStream(stream, buffs, samps_to_send, flags);
-
-            if (ret == SOAPY_SDR_TIMEOUT) {
-                continue;
-            }
-            else if (ret == SOAPY_SDR_OVERFLOW) {
-                overflows++;
-                continue;
-            }
-            else if (ret == SOAPY_SDR_UNDERFLOW) {
-                underflows++;
-                continue;
-            }
-
-            if (ret < 0) {
-                etiLog.level(error) << "Unexpected stream error " <<
-                    SoapySDR::errToStr(ret);
-                running = false;
-            }
-
-            num_acc_samps += ret;
-        }
-    }
-}
-
-int OutputSoapy::process(Buffer* dataIn)
-{
-    if (first_run) {
-        m_worker.start(m_device);
-        first_run = false;
-    }
-    else if (!m_worker.running) {
-        etiLog.level(error) << "OutputSoapy: worker thread died";
-        throw std::runtime_error("Fault in OutputSoapy");
-    }
-
-    SoapyWorkerFrameData frame;
-    m_eti_source->calculateTimestamp(frame.ts);
-
-
-    if (frame.ts.fct == -1) {
-        etiLog.level(info) <<
-            "OutputSoapy: dropping one frame with invalid FCT";
-    }
-    else {
-        const uint8_t* pInData = reinterpret_cast<uint8_t*>(dataIn->getData());
-        frame.buf.resize(dataIn->getLength());
-        std::copy(pInData, pInData + dataIn->getLength(),
-                frame.buf.begin());
-        m_worker.queue.push_wait_if_full(frame, FRAMES_MAX_SIZE);
-    }
-
-    return dataIn->getLength();
-}
-
-
-void OutputSoapy::setETISource(EtiSource *etiSource)
-{
-    m_eti_source = etiSource;
-}
-
-void OutputSoapy::set_parameter(const string& parameter, const string& value)
-{
-    stringstream ss(value);
-    ss.exceptions ( stringstream::failbit | stringstream::badbit );
-
-    if (parameter == "txgain") {
-        ss >> m_conf.txgain;
-        m_device->setGain(SOAPY_SDR_TX, 0, m_conf.txgain);
-    }
-    else if (parameter == "freq") {
-        ss >> m_conf.frequency;
-        m_device->setFrequency(SOAPY_SDR_TX, 0, m_conf.frequency);
-    m_conf.frequency = m_device->getFrequency(SOAPY_SDR_TX, 0);
-    }
-    else if (parameter == "underflows") {
-        throw ParameterError("Parameter 'underflows' is read-only");
-    }
-    else if (parameter == "overflows") {
-        throw ParameterError("Parameter 'overflows' is read-only");
-    }
-    else {
-        stringstream ss_err;
-        ss_err << "Parameter '" << parameter
-            << "' is not exported by controllable " << get_rc_name();
-        throw ParameterError(ss_err.str());
-    }
-}
-
-const string OutputSoapy::get_parameter(const string& parameter) const
-{
-    stringstream ss;
-    if (parameter == "txgain") {
-        ss << m_conf.txgain;
-    }
-    else if (parameter == "freq") {
-        ss << m_conf.frequency;
-    }
-    else if (parameter == "underflows") {
-        ss << m_worker.underflows;
-    }
-    else if (parameter == "overflows") {
-        ss << m_worker.overflows;
-    }
-    else {
-        ss << "Parameter '" << parameter <<
-            "' is not exported by controllable " << get_rc_name();
-        throw ParameterError(ss.str());
-    }
-    return ss.str();
-}
-
-#endif // HAVE_SOAPYSDR
-
diff --git a/src/OutputSoapy.h b/src/OutputSoapy.h
deleted file mode 100644
index 230f11b..0000000
--- a/src/OutputSoapy.h
+++ /dev/null
@@ -1,138 +0,0 @@
-/*
-   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
-   Queen in Right of Canada (Communications Research Center Canada)
-
-   Copyright (C) 2017
-   Matthias P. Braendli, matthias.braendli@mpb.li
-
-    http://opendigitalradio.org
-
-DESCRIPTION:
-   It is an output driver using the SoapySDR library that can output to
-   many devices.
-*/
-
-/*
-   This file is part of ODR-DabMod.
-
-   ODR-DabMod is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as
-   published by the Free Software Foundation, either version 3 of the
-   License, or (at your option) any later version.
-
-   ODR-DabMod is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#pragma once
-
-#ifdef HAVE_CONFIG_H
-#   include <config.h>
-#endif
-
-#ifdef HAVE_SOAPYSDR
-#include <SoapySDR/Version.hpp>
-#include <SoapySDR/Modules.hpp>
-#include <SoapySDR/Registry.hpp>
-#include <SoapySDR/Device.hpp>
-
-#include <string>
-#include <memory>
-
-#include "ModPlugin.h"
-#include "EtiReader.h"
-#include "RemoteControl.h"
-#include "ThreadsafeQueue.h"
-
-typedef std::complex<float> complexf;
-
-/* This structure is used as initial configuration for the Soapy output.
- * It must also contain all remote-controllable settings, otherwise
- * they will get lost on a modulator restart. */
-struct OutputSoapyConfig {
-    std::string device;
-
-    long masterClockRate = 32768000;
-    unsigned sampleRate = 2048000;
-    double frequency = 0.0;
-    double txgain = 0.0;
-    unsigned dabMode = 0;
-};
-
-// Each frame contains one OFDM frame, and its
-// associated timestamp
-struct SoapyWorkerFrameData {
-    // Buffer holding frame data
-    std::vector<uint8_t> buf;
-
-    // A full timestamp contains a TIST according to standard
-    // and time information within MNSC with tx_second.
-    struct frame_timestamp ts;
-};
-
-class SoapyWorker
-{
-    public:
-        ThreadsafeQueue<SoapyWorkerFrameData> queue;
-        SoapySDR::Device *m_device;
-        std::atomic<bool> running;
-        size_t underflows;
-        size_t overflows;
-
-        SoapyWorker() {}
-        SoapyWorker(const SoapyWorker&) = delete;
-        SoapyWorker operator=(const SoapyWorker&) = delete;
-        ~SoapyWorker() { stop(); }
-
-        void start(SoapySDR::Device *device);
-        void stop(void);
-
-    private:
-        std::thread m_thread;
-
-        void process_start(void);
-        void process(SoapySDR::Stream *stream);
-};
-
-class OutputSoapy: public ModOutput, public RemoteControllable
-{
-    public:
-        OutputSoapy(OutputSoapyConfig& config);
-        OutputSoapy(const OutputSoapy& other) = delete;
-        OutputSoapy& operator=(const OutputSoapy& other) = delete;
-        ~OutputSoapy();
-
-        int process(Buffer* dataIn);
-
-        const char* name() { return "OutputSoapy"; }
-
-        void setETISource(EtiSource *etiSource);
-
-        /*********** REMOTE CONTROL ***************/
-
-        /* Base function to set parameters. */
-        virtual void set_parameter(const std::string& parameter,
-                const std::string& value);
-
-        /* Getting a parameter always returns a string. */
-        virtual const std::string get_parameter(
-                const std::string& parameter) const;
-
-
-    protected:
-        SoapyWorker m_worker;
-        EtiSource *m_eti_source;
-        OutputSoapyConfig& m_conf;
-
-        SoapySDR::Device *m_device;
-
-        bool first_run = true;
-};
-
-
-#endif //HAVE_SOAPYSDR
diff --git a/src/OutputUHD.cpp b/src/OutputUHD.cpp
deleted file mode 100644
index b533075..0000000
--- a/src/OutputUHD.cpp
+++ /dev/null
@@ -1,1035 +0,0 @@
-/*
-   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
-   Queen in Right of Canada (Communications Research Center Canada)
-
-   Copyright (C) 2017
-   Matthias P. Braendli, matthias.braendli@mpb.li
-
-    http://opendigitalradio.org
- */
-/*
-   This file is part of ODR-DabMod.
-
-   ODR-DabMod is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as
-   published by the Free Software Foundation, either version 3 of the
-   License, or (at your option) any later version.
-
-   ODR-DabMod is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include "OutputUHD.h"
-
-#ifdef HAVE_OUTPUT_UHD
-
-#include "PcDebug.h"
-#include "Log.h"
-#include "RemoteControl.h"
-#include "Utils.h"
-
-#include <boost/thread/future.hpp>
-
-#include <uhd/utils/msg.hpp>
-
-#include <cmath>
-#include <iostream>
-#include <assert.h>
-#include <stdexcept>
-#include <stdio.h>
-#include <time.h>
-#include <errno.h>
-#include <unistd.h>
-#include <pthread.h>
-
-using namespace std;
-
-// Maximum number of frames that can wait in frames
-static const size_t FRAMES_MAX_SIZE = 8;
-
-typedef std::complex<float> complexf;
-
-std::string stringtrim(const std::string &s)
-{
-    auto wsfront = std::find_if_not(s.begin(), s.end(),
-            [](int c){ return std::isspace(c);} );
-    return std::string(wsfront,
-            std::find_if_not(s.rbegin(),
-                std::string::const_reverse_iterator(wsfront),
-                [](int c){ return std::isspace(c);} ).base());
-}
-
-void uhd_msg_handler(uhd::msg::type_t type, const std::string &msg)
-{
-    if (type == uhd::msg::warning) {
-        etiLog.level(warn) << "UHD Warning: " << msg;
-    }
-    else if (type == uhd::msg::error) {
-        etiLog.level(error) << "UHD Error: " << msg;
-    }
-    else {
-        // do not print very short U messages and such
-        if (stringtrim(msg).size() != 1) {
-            etiLog.level(debug) << "UHD Message: " << msg;
-        }
-    }
-}
-
-static void tune_usrp_to(
-        uhd::usrp::multi_usrp::sptr usrp,
-        double lo_offset,
-        double frequency)
-{
-    if (lo_offset != 0.0) {
-        etiLog.level(info) << std::fixed << std::setprecision(3) <<
-            "OutputUHD:Setting freq to " << frequency <<
-            "  with LO offset " << lo_offset << "...";
-
-        const auto tr = uhd::tune_request_t(frequency, lo_offset);
-        uhd::tune_result_t result = usrp->set_tx_freq(tr);
-
-        etiLog.level(debug) << "OutputUHD:" <<
-            std::fixed << std::setprecision(0) <<
-            " Target RF: " << result.target_rf_freq <<
-            " Actual RF: " << result.actual_rf_freq <<
-            " Target DSP: " << result.target_dsp_freq <<
-            " Actual DSP: " << result.actual_dsp_freq;
-    }
-    else {
-        //set the centre frequency
-        etiLog.level(info) << std::fixed << std::setprecision(3) <<
-            "OutputUHD:Setting freq to " << frequency << "...";
-        usrp->set_tx_freq(frequency);
-    }
-
-    usrp->set_rx_freq(frequency);
-}
-
-// Check function for GPS TIMELOCK sensor from the ODR LEA-M8F board GPSDO
-bool check_gps_timelock(uhd::usrp::multi_usrp::sptr usrp)
-{
-    try {
-        std::string sensor_value(
-                usrp->get_mboard_sensor("gps_timelock", 0).to_pp_string());
-
-        if (sensor_value.find("TIME LOCKED") == std::string::npos) {
-            etiLog.level(warn) << "OutputUHD: gps_timelock " << sensor_value;
-            return false;
-        }
-
-        return true;
-    }
-    catch (uhd::lookup_error &e) {
-        etiLog.level(warn) << "OutputUHD: no gps_timelock sensor";
-        return false;
-    }
-}
-
-// Check function for GPS LOCKED sensor from the Ettus GPSDO
-bool check_gps_locked(uhd::usrp::multi_usrp::sptr usrp)
-{
-    try {
-        uhd::sensor_value_t sensor_value(
-                usrp->get_mboard_sensor("gps_locked", 0));
-        if (not sensor_value.to_bool()) {
-            etiLog.level(warn) << "OutputUHD: gps_locked " <<
-                sensor_value.to_pp_string();
-            return false;
-        }
-
-        return true;
-    }
-    catch (uhd::lookup_error &e) {
-        etiLog.level(warn) << "OutputUHD: no gps_locked sensor";
-        return false;
-    }
-}
-
-
-OutputUHD::OutputUHD(
-        OutputUHDConfig& config) :
-    ModOutput(),
-    RemoteControllable("uhd"),
-    myConf(config),
-    // Since we don't know the buffer size, we cannot initialise
-    // the buffers at object initialisation.
-    myDelayBuf(0),
-    running(false)
-{
-    myConf.muting = true;     // is remote-controllable, and reset by the GPS fix check
-    myConf.staticDelayUs = 0; // is remote-controllable
-
-    // Variables needed for GPS fix check
-    first_gps_fix_check.tv_sec = 0;
-    last_gps_fix_check.tv_sec = 0;
-    time_last_frame.tv_sec = 0;
-
-
-    std::stringstream device;
-    device << myConf.device;
-
-    if (myConf.masterClockRate != 0) {
-        if (device.str() != "") {
-            device << ",";
-        }
-        device << "master_clock_rate=" << myConf.masterClockRate;
-    }
-
-    if (myConf.usrpType != "") {
-        if (device.str() != "") {
-            device << ",";
-        }
-        device << "type=" << myConf.usrpType;
-    }
-
-    MDEBUG("OutputUHD::OutputUHD(device: %s) @ %p\n",
-            device.str().c_str(), this);
-
-    /* register the parameters that can be remote controlled */
-    RC_ADD_PARAMETER(txgain, "UHD analog daughterboard TX gain");
-    RC_ADD_PARAMETER(rxgain, "UHD analog daughterboard RX gain for DPD feedback");
-    RC_ADD_PARAMETER(freq, "UHD transmission frequency");
-    RC_ADD_PARAMETER(muting, "Mute the output by stopping the transmitter");
-    RC_ADD_PARAMETER(staticdelay, "Set static delay (uS) between 0 and 96000");
-    RC_ADD_PARAMETER(underruns, "Read-only counter of number of underruns");
-    RC_ADD_PARAMETER(latepackets, "Read-only counter of number of late packets");
-    RC_ADD_PARAMETER(frames, "Read-only counter of number of frames modulated");
-
-    uhd::msg::register_handler(uhd_msg_handler);
-
-    uhd::set_thread_priority_safe();
-
-    etiLog.log(info, "OutputUHD:Creating the usrp device with: %s...",
-            device.str().c_str());
-
-    myUsrp = uhd::usrp::multi_usrp::make(device.str());
-
-    etiLog.log(info, "OutputUHD:Using device: %s...",
-            myUsrp->get_pp_string().c_str());
-
-    if (myConf.masterClockRate != 0.0) {
-        double master_clk_rate = myUsrp->get_master_clock_rate();
-        etiLog.log(debug, "OutputUHD:Checking master clock rate: %f...",
-                master_clk_rate);
-
-        if (fabs(master_clk_rate - myConf.masterClockRate) >
-                (myConf.masterClockRate * 1e-6)) {
-            throw std::runtime_error("Cannot set USRP master_clock_rate. Aborted.");
-        }
-    }
-
-    MDEBUG("OutputUHD:Setting REFCLK and PPS input...\n");
-
-    if (myConf.refclk_src == "gpsdo-ettus") {
-        myUsrp->set_clock_source("gpsdo");
-    }
-    else {
-        myUsrp->set_clock_source(myConf.refclk_src);
-    }
-    myUsrp->set_time_source(myConf.pps_src);
-
-    if (myConf.subDevice != "") {
-        myUsrp->set_tx_subdev_spec(uhd::usrp::subdev_spec_t(myConf.subDevice),
-                uhd::usrp::multi_usrp::ALL_MBOARDS);
-    }
-
-    etiLog.level(debug) << "UHD clock source is " << myUsrp->get_clock_source(0);
-
-    etiLog.level(debug) << "UHD time source is " << myUsrp->get_time_source(0);
-
-    myUsrp->set_tx_rate(myConf.sampleRate);
-    etiLog.log(debug, "OutputUHD:Set rate to %d. Actual TX Rate: %f sps...",
-            myConf.sampleRate, myUsrp->get_tx_rate());
-
-    if (fabs(myUsrp->get_tx_rate() / myConf.sampleRate) >
-             myConf.sampleRate * 1e-6) {
-        throw std::runtime_error("Cannot set USRP sample rate. Aborted.");
-    }
-
-    tune_usrp_to(myUsrp, myConf.lo_offset, myConf.frequency);
-
-    myConf.frequency = myUsrp->get_tx_freq();
-    etiLog.level(info) << std::fixed << std::setprecision(3) <<
-        "OutputUHD:Actual TX frequency: " << myConf.frequency;
-
-    etiLog.level(info) << std::fixed << std::setprecision(3) <<
-        "OutputUHD:Actual RX frequency: " << myUsrp->get_tx_freq();
-
-    myUsrp->set_tx_gain(myConf.txgain);
-    etiLog.log(debug, "OutputUHD:Actual TX Gain: %f", myUsrp->get_tx_gain());
-
-    etiLog.log(debug, "OutputUHD:Mute on missing timestamps: %s",
-            myConf.muteNoTimestamps ? "enabled" : "disabled");
-
-    // preparing output thread worker data
-    sync_and_ts_valid = false;
-
-    SetDelayBuffer(myConf.dabMode);
-
-    myUsrp->set_rx_rate(myConf.sampleRate);
-    etiLog.log(debug, "OutputUHD:Actual RX Rate: %f sps.", myUsrp->get_rx_rate());
-
-    myUsrp->set_rx_antenna("RX2");
-    etiLog.log(debug, "OutputUHD:Set RX Antenna: %s",
-            myUsrp->get_rx_antenna().c_str());
-
-    myUsrp->set_rx_gain(myConf.rxgain);
-    etiLog.log(debug, "OutputUHD:Actual RX Gain: %f", myUsrp->get_rx_gain());
-
-    uhdFeedback = std::make_shared<OutputUHDFeedback>(
-            myUsrp, myConf.dpdFeedbackServerPort, myConf.sampleRate);
-
-    MDEBUG("OutputUHD:UHD ready.\n");
-}
-
-bool OutputUHD::refclk_loss_needs_check() const
-{
-    if (suppress_refclk_loss_check) {
-        return false;
-    }
-    return myConf.refclk_src != "internal";
-}
-
-bool OutputUHD::gpsfix_needs_check() const
-{
-    if (myConf.refclk_src == "internal") {
-        return false;
-    }
-    else if (myConf.refclk_src == "gpsdo") {
-        return (myConf.maxGPSHoldoverTime != 0);
-    }
-    else if (myConf.refclk_src == "gpsdo-ettus") {
-        return (myConf.maxGPSHoldoverTime != 0);
-    }
-    else {
-        return false;
-    }
-}
-
-bool OutputUHD::gpsdo_is_ettus() const
-{
-    return (myConf.refclk_src == "gpsdo-ettus");
-}
-
-OutputUHD::~OutputUHD()
-{
-    stop_threads();
-}
-
-void OutputUHD::stop_threads()
-{
-    running.store(false);
-    uhd_thread.interrupt();
-    uhd_thread.join();
-    async_rx_thread.join();
-}
-
-
-void OutputUHD::setETISource(EtiSource *etiSource)
-{
-    myEtiSource = etiSource;
-}
-
-int transmission_frame_duration_ms(unsigned int dabMode)
-{
-    switch (dabMode) {
-        // could happen when called from constructor and we take the mode from ETI
-        case 0: return 0;
-
-        case 1: return 96;
-        case 2: return 24;
-        case 3: return 24;
-        case 4: return 48;
-        default:
-            throw std::runtime_error("OutputUHD: invalid DAB mode");
-    }
-}
-
-void OutputUHD::SetDelayBuffer(unsigned int dabMode)
-{
-    // find out the duration of the transmission frame (Table 2 in ETSI 300 401)
-    myTFDurationMs = transmission_frame_duration_ms(dabMode);
-
-    // The buffer size equals the number of samples per transmission frame so
-    // we calculate it by multiplying the duration of the transmission frame
-    // with the samplerate.
-    myDelayBuf.resize(myTFDurationMs * myConf.sampleRate / 1000);
-}
-
-int OutputUHD::process(Buffer* dataIn)
-{
-    if (not gps_fix_verified) {
-        if (gpsfix_needs_check()) {
-            initial_gps_check();
-
-            if (num_checks_without_gps_fix == 0) {
-                set_usrp_time();
-                gps_fix_verified = true;
-                myConf.muting = false;
-            }
-        }
-        else {
-            set_usrp_time();
-            gps_fix_verified = true;
-            myConf.muting = false;
-        }
-    }
-    else {
-        if (first_run) {
-            etiLog.level(debug) << "OutputUHD: UHD initialising...";
-
-            // we only set the delay buffer from the dab mode signaled in ETI if the
-            // dab mode was not set in contructor
-            if (myTFDurationMs == 0) {
-                SetDelayBuffer(myEtiSource->getMode());
-            }
-
-            running.store(true);
-            uhd_thread = boost::thread(&OutputUHD::workerthread, this);
-            async_rx_thread = boost::thread(
-                    &OutputUHD::print_async_thread, this);
-
-            lastLen = dataIn->getLength();
-            first_run = false;
-            etiLog.level(debug) << "OutputUHD: UHD initialising complete";
-        }
-
-        if (lastLen != dataIn->getLength()) {
-            // I expect that this never happens.
-            etiLog.level(emerg) <<
-                "OutputUHD: Fatal error, input length changed from " << lastLen <<
-                " to " << dataIn->getLength();
-            throw std::runtime_error("Non-constant input length!");
-        }
-
-        sync_and_ts_valid = myConf.enableSync and
-            myEtiSource->sourceContainsTimestamp();
-
-        if (gpsfix_needs_check()) {
-            try {
-                check_gps();
-            }
-            catch (std::runtime_error& e) {
-                running.store(false);
-                etiLog.level(error) << e.what();
-            }
-        }
-
-        // Prepare the frame for the worker
-        UHDWorkerFrameData frame;
-        frame.buf.resize(dataIn->getLength());
-
-        // calculate delay and fill buffer
-        uint32_t noSampleDelay = (myConf.staticDelayUs * (myConf.sampleRate / 1000)) / 1000;
-        uint32_t noByteDelay = noSampleDelay * sizeof(complexf);
-
-        const uint8_t* pInData = (uint8_t*)dataIn->getData();
-
-        uint8_t *pTmp = &frame.buf[0];
-        if (noByteDelay) {
-            // copy remain from delaybuf
-            memcpy(pTmp, &myDelayBuf[0], noByteDelay);
-            // copy new data
-            memcpy(&pTmp[noByteDelay], pInData, dataIn->getLength() - noByteDelay);
-            // copy remaining data to delay buf
-            memcpy(&myDelayBuf[0], &pInData[dataIn->getLength() - noByteDelay], noByteDelay);
-        }
-        else {
-            std::copy(pInData, pInData + dataIn->getLength(),
-                    frame.buf.begin());
-        }
-
-        myEtiSource->calculateTimestamp(frame.ts);
-
-        if (not running.load()) {
-            uhd_thread.interrupt();
-            uhd_thread.join();
-            async_rx_thread.join();
-            first_run = true;
-
-            etiLog.level(error) << "OutputUHD UHD worker failed";
-            throw std::runtime_error("UHD worker failed");
-        }
-
-        if (frame.ts.fct == -1) {
-            etiLog.level(info) <<
-                "OutputUHD: dropping one frame with invalid FCT";
-        }
-        else {
-            try {
-                uhdFeedback->set_tx_frame(frame.buf, frame.ts);
-            }
-            catch (const runtime_error& e) {
-                etiLog.level(warn) <<
-                    "OutputUHD: Feedback server failed, restarting...";
-
-                uhdFeedback = std::make_shared<OutputUHDFeedback>(
-                        myUsrp, myConf.dpdFeedbackServerPort, myConf.sampleRate);
-            }
-
-            size_t num_frames = m_frames.push_wait_if_full(frame,
-                    FRAMES_MAX_SIZE);
-            etiLog.log(trace, "UHD,push %zu", num_frames);
-        }
-    }
-
-    return dataIn->getLength();
-}
-
-
-void OutputUHD::set_usrp_time()
-{
-    if (myConf.enableSync and (myConf.pps_src == "none")) {
-        etiLog.level(warn) <<
-            "OutputUHD: WARNING:"
-            " you are using synchronous transmission without PPS input!";
-
-        struct timespec now;
-        if (clock_gettime(CLOCK_REALTIME, &now)) {
-            perror("OutputUHD:Error: could not get time: ");
-            etiLog.level(error) << "OutputUHD: could not get time";
-        }
-        else {
-            myUsrp->set_time_now(uhd::time_spec_t(now.tv_sec));
-            etiLog.level(info) << "OutputUHD: Setting USRP time to " <<
-                std::fixed <<
-                uhd::time_spec_t(now.tv_sec).get_real_secs();
-        }
-    }
-
-    if (myConf.pps_src != "none") {
-        /* handling time for synchronisation: wait until the next full
-         * second, and set the USRP time at next PPS */
-        struct timespec now;
-        time_t seconds;
-        if (clock_gettime(CLOCK_REALTIME, &now)) {
-            etiLog.level(error) << "OutputUHD: could not get time :" <<
-                strerror(errno);
-            throw std::runtime_error("OutputUHD: could not get time.");
-        }
-        else {
-            seconds = now.tv_sec;
-
-            MDEBUG("OutputUHD:sec+1: %ld ; now: %ld ...\n", seconds+1, now.tv_sec);
-            while (seconds + 1 > now.tv_sec) {
-                usleep(1);
-                if (clock_gettime(CLOCK_REALTIME, &now)) {
-                    etiLog.level(error) << "OutputUHD: could not get time :" <<
-                        strerror(errno);
-                    throw std::runtime_error("OutputUHD: could not get time.");
-                }
-            }
-            MDEBUG("OutputUHD:sec+1: %ld ; now: %ld ...\n", seconds+1, now.tv_sec);
-            /* We are now shortly after the second change. */
-
-            usleep(200000); // 200ms, we want the PPS to be later
-            myUsrp->set_time_unknown_pps(uhd::time_spec_t(seconds + 2));
-            etiLog.level(info) << "OutputUHD: Setting USRP time next pps to " <<
-                std::fixed <<
-                uhd::time_spec_t(seconds + 2).get_real_secs();
-        }
-
-        usleep(1e6);
-        etiLog.log(info,  "OutputUHD: USRP time %f\n",
-                myUsrp->get_time_now().get_real_secs());
-    }
-}
-
-void OutputUHD::initial_gps_check()
-{
-    if (first_gps_fix_check.tv_sec == 0) {
-        etiLog.level(info) << "Waiting for GPS fix";
-
-        if (clock_gettime(CLOCK_MONOTONIC, &first_gps_fix_check) != 0) {
-            stringstream ss;
-            ss << "clock_gettime failure: " << strerror(errno);
-            throw std::runtime_error(ss.str());
-        }
-    }
-
-    check_gps();
-
-    if (last_gps_fix_check.tv_sec >
-            first_gps_fix_check.tv_sec + initial_gps_fix_wait) {
-        stringstream ss;
-        ss << "GPS did not show time lock in " << initial_gps_fix_wait << " seconds";
-        throw std::runtime_error(ss.str());
-    }
-
-    if (time_last_frame.tv_sec == 0) {
-        if (clock_gettime(CLOCK_MONOTONIC, &time_last_frame) != 0) {
-            stringstream ss;
-            ss << "clock_gettime failure: " << strerror(errno);
-            throw std::runtime_error(ss.str());
-        }
-    }
-
-    struct timespec now;
-    if (clock_gettime(CLOCK_MONOTONIC, &now) != 0) {
-        stringstream ss;
-        ss << "clock_gettime failure: " << strerror(errno);
-        throw std::runtime_error(ss.str());
-    }
-
-    long delta_us = timespecdiff_us(time_last_frame, now);
-    long wait_time_us = transmission_frame_duration_ms(myConf.dabMode);
-
-    if (wait_time_us - delta_us > 0) {
-        usleep(wait_time_us - delta_us);
-    }
-
-    time_last_frame.tv_nsec += wait_time_us * 1000;
-    if (time_last_frame.tv_nsec >= 1000000000L) {
-        time_last_frame.tv_nsec -= 1000000000L;
-        time_last_frame.tv_sec++;
-    }
-}
-
-void OutputUHD::check_gps()
-{
-    struct timespec time_now;
-    if (clock_gettime(CLOCK_MONOTONIC, &time_now) != 0) {
-        stringstream ss;
-        ss << "clock_gettime failure: " << strerror(errno);
-        throw std::runtime_error(ss.str());
-    }
-
-    // Divide interval by two because we alternate between
-    // launch and check
-    if (gpsfix_needs_check() and
-            last_gps_fix_check.tv_sec + gps_fix_check_interval/2.0 <
-            time_now.tv_sec) {
-        last_gps_fix_check = time_now;
-
-        // Alternate between launching thread and checking the
-        // result.
-        if (gps_fix_task.joinable()) {
-            if (gps_fix_future.has_value()) {
-
-                gps_fix_future.wait();
-
-                gps_fix_task.join();
-
-                if (not gps_fix_future.get()) {
-                    if (num_checks_without_gps_fix == 0) {
-                        etiLog.level(alert) <<
-                            "OutputUHD: GPS Time Lock lost";
-                    }
-                    num_checks_without_gps_fix++;
-                }
-                else {
-                    if (num_checks_without_gps_fix) {
-                        etiLog.level(info) <<
-                            "OutputUHD: GPS Time Lock recovered";
-                    }
-                    num_checks_without_gps_fix = 0;
-                }
-
-                if (gps_fix_check_interval * num_checks_without_gps_fix >
-                        myConf.maxGPSHoldoverTime) {
-                    std::stringstream ss;
-                    ss << "Lost GPS Time Lock for " << gps_fix_check_interval *
-                        num_checks_without_gps_fix << " seconds";
-                    throw std::runtime_error(ss.str());
-                }
-            }
-        }
-        else {
-            // Checking the sensor here takes too much
-            // time, it has to be done in a separate thread.
-            if (gpsdo_is_ettus()) {
-                gps_fix_pt = boost::packaged_task<bool>(
-                        boost::bind(check_gps_locked, myUsrp) );
-            }
-            else {
-                gps_fix_pt = boost::packaged_task<bool>(
-                        boost::bind(check_gps_timelock, myUsrp) );
-            }
-            gps_fix_future = gps_fix_pt.get_future();
-
-            gps_fix_task = boost::thread(boost::move(gps_fix_pt));
-        }
-    }
-}
-
-void OutputUHD::workerthread()
-{
-    // Set thread priority to realtime
-    if (int ret = set_realtime_prio(1)) {
-        etiLog.level(error) << "Could not set priority for UHD worker:" << ret;
-    }
-
-    set_thread_name("uhdworker");
-
-    last_tx_time_initialised = false;
-
-    uhd::stream_args_t stream_args("fc32"); //complex floats
-    myTxStream = myUsrp->get_tx_stream(stream_args);
-
-    md.start_of_burst = false;
-    md.end_of_burst   = false;
-
-    num_underflows   = 0;
-    num_late_packets = 0;
-
-    size_t last_num_underflows = 0;
-    size_t pop_prebuffering = FRAMES_MAX_SIZE;
-
-    while (running.load()) {
-        md.has_time_spec  = false;
-        md.time_spec      = uhd::time_spec_t(0.0);
-
-        struct UHDWorkerFrameData frame;
-        etiLog.log(trace, "UHD,wait");
-        m_frames.wait_and_pop(frame, pop_prebuffering);
-        etiLog.log(trace, "UHD,pop");
-
-        handle_frame(&frame);
-        num_frames_modulated++;
-
-        /* Ensure we fill frames after every underrun and
-         * at startup to reduce underrun likelihood. */
-        if (last_num_underflows < num_underflows) {
-            pop_prebuffering = FRAMES_MAX_SIZE;
-        }
-        else {
-            pop_prebuffering = 1;
-        }
-        last_num_underflows = num_underflows;
-    }
-    running.store(false);
-    etiLog.level(warn) << "UHD worker terminated";
-}
-
-void OutputUHD::handle_frame(const struct UHDWorkerFrameData *frame)
-{
-    // Transmit timeout
-    static const double tx_timeout = 20.0;
-
-    // Check for ref_lock
-    if (refclk_loss_needs_check()) {
-        try {
-            if (not myUsrp->get_mboard_sensor("ref_locked", 0).to_bool()) {
-                etiLog.log(alert,
-                        "OutputUHD: External reference clock lock lost !");
-                if (myConf.refclk_lock_loss_behaviour == CRASH) {
-                    throw std::runtime_error(
-                            "OutputUHD: External reference clock lock lost.");
-                }
-            }
-        }
-        catch (uhd::lookup_error &e) {
-            suppress_refclk_loss_check = true;
-            etiLog.log(warn, "OutputUHD: This USRP does not have mboard "
-                    "sensor for ext clock loss. Check disabled.");
-        }
-    }
-
-    double usrp_time = myUsrp->get_time_now().get_real_secs();
-    bool timestamp_discontinuity = false;
-
-    if (sync_and_ts_valid) {
-        // Tx time from MNSC and TIST
-        uint32_t tx_second = frame->ts.timestamp_sec;
-        uint32_t tx_pps    = frame->ts.timestamp_pps;
-
-        if (!frame->ts.timestamp_valid) {
-            /* We have not received a full timestamp through
-             * MNSC. We sleep through the frame.
-             */
-            etiLog.level(info) <<
-                "OutputUHD: Throwing sample " << frame->ts.fct <<
-                " away: incomplete timestamp " << tx_second <<
-                " / " << tx_pps;
-            usleep(20000); //TODO should this be TM-dependant ?
-            return;
-        }
-
-        if (last_tx_time_initialised) {
-            const size_t sizeIn = frame->buf.size() / sizeof(complexf);
-            uint64_t increment = (uint64_t)sizeIn * 16384000ul /
-                                 (uint64_t)myConf.sampleRate;
-                                  // samps  * ticks/s  / (samps/s)
-                                  // (samps * ticks * s) / (s * samps)
-                                  // ticks
-
-            uint32_t expected_sec = last_tx_second + increment / 16384000ul;
-            uint32_t expected_pps = last_tx_pps + increment % 16384000ul;
-
-            while (expected_pps >= 16384000) {
-                expected_sec++;
-                expected_pps -= 16384000;
-            }
-
-            if (expected_sec != tx_second or
-                    expected_pps != tx_pps) {
-                etiLog.level(warn) << "OutputUHD: timestamp irregularity!" <<
-                    std::fixed <<
-                    " Expected " <<
-                    expected_sec << "+" << (double)expected_pps/16384000.0 <<
-                    "(" << expected_pps << ")" <<
-                    " Got " <<
-                    tx_second << "+" << (double)tx_pps/16384000.0 <<
-                    "(" << tx_pps << ")";
-
-                timestamp_discontinuity = true;
-            }
-        }
-
-        last_tx_second = tx_second;
-        last_tx_pps    = tx_pps;
-        last_tx_time_initialised = true;
-
-        double pps_offset = tx_pps / 16384000.0;
-
-        md.has_time_spec = true;
-        md.time_spec = uhd::time_spec_t(tx_second, pps_offset);
-        etiLog.log(trace, "UHD,tist %f", md.time_spec.get_real_secs());
-
-        // md is defined, let's do some checks
-        if (md.time_spec.get_real_secs() + tx_timeout < usrp_time) {
-            etiLog.level(warn) <<
-                "OutputUHD: Timestamp in the past! offset: " <<
-                std::fixed <<
-                md.time_spec.get_real_secs() - usrp_time <<
-                "  (" << usrp_time << ")"
-                " frame " << frame->ts.fct <<
-                ", tx_second " << tx_second <<
-                ", pps " << pps_offset;
-            return;
-        }
-
-        if (md.time_spec.get_real_secs() > usrp_time + TIMESTAMP_ABORT_FUTURE) {
-            etiLog.level(error) <<
-                "OutputUHD: Timestamp way too far in the future! offset: " <<
-                std::fixed <<
-                md.time_spec.get_real_secs() - usrp_time;
-            throw std::runtime_error("Timestamp error. Aborted.");
-        }
-    }
-    else { // !sync_and_ts_valid
-        if (myConf.muting or myConf.muteNoTimestamps) {
-            /* There was some error decoding the timestamp */
-            if (myConf.muting) {
-                etiLog.log(info,
-                        "OutputUHD: Muting sample %d requested\n",
-                        frame->ts.fct);
-            }
-            else {
-                etiLog.log(info,
-                        "OutputUHD: Muting sample %d : no timestamp\n",
-                        frame->ts.fct);
-            }
-            usleep(20000);
-            return;
-        }
-    }
-
-    tx_frame(frame, timestamp_discontinuity);
-}
-
-void OutputUHD::tx_frame(const struct UHDWorkerFrameData *frame, bool ts_update)
-{
-    const double tx_timeout = 20.0;
-    const size_t sizeIn = frame->buf.size() / sizeof(complexf);
-    const complexf* in_data = reinterpret_cast<const complexf*>(&frame->buf[0]);
-
-    size_t usrp_max_num_samps = myTxStream->get_max_num_samps();
-    size_t num_acc_samps = 0; //number of accumulated samples
-    while (running.load() and (not myConf.muting) and (num_acc_samps < sizeIn)) {
-        size_t samps_to_send = std::min(sizeIn - num_acc_samps, usrp_max_num_samps);
-
-        uhd::tx_metadata_t md_tx = md;
-
-        //ensure the the last packet has EOB set if the timestamps has been
-        //refreshed and need to be reconsidered.
-        md_tx.end_of_burst = (
-                sync_and_ts_valid and
-                (frame->ts.timestamp_refresh or ts_update) and
-                samps_to_send <= usrp_max_num_samps );
-
-
-        //send a single packet
-        size_t num_tx_samps = myTxStream->send(
-                &in_data[num_acc_samps],
-                samps_to_send, md_tx, tx_timeout);
-        etiLog.log(trace, "UHD,sent %zu of %zu", num_tx_samps, samps_to_send);
-
-        num_acc_samps += num_tx_samps;
-
-        md_tx.time_spec = md.time_spec +
-            uhd::time_spec_t(0, num_tx_samps/myConf.sampleRate);
-
-        if (num_tx_samps == 0) {
-            etiLog.log(warn,
-                    "OutputUHD::workerthread() unable to write to device, skipping frame!\n");
-            break;
-        }
-    }
-}
-
-void OutputUHD::print_async_thread()
-{
-    while (running.load()) {
-        uhd::async_metadata_t async_md;
-        if (myUsrp->get_device()->recv_async_msg(async_md, 1)) {
-            const char* uhd_async_message = "";
-            bool failure = false;
-            switch (async_md.event_code) {
-                case uhd::async_metadata_t::EVENT_CODE_BURST_ACK:
-                    break;
-                case uhd::async_metadata_t::EVENT_CODE_UNDERFLOW:
-                    uhd_async_message = "Underflow";
-                    num_underflows++;
-                    break;
-                case uhd::async_metadata_t::EVENT_CODE_SEQ_ERROR:
-                    uhd_async_message = "Packet loss between host and device.";
-                    failure = true;
-                    break;
-                case uhd::async_metadata_t::EVENT_CODE_TIME_ERROR:
-                    uhd_async_message = "Packet had time that was late.";
-                    num_late_packets++;
-                    break;
-                case uhd::async_metadata_t::EVENT_CODE_UNDERFLOW_IN_PACKET:
-                    uhd_async_message = "Underflow occurred inside a packet.";
-                    failure = true;
-                    break;
-                case uhd::async_metadata_t::EVENT_CODE_SEQ_ERROR_IN_BURST:
-                    uhd_async_message = "Packet loss within a burst.";
-                    failure = true;
-                    break;
-                default:
-                    uhd_async_message = "unknown event code";
-                    failure = true;
-                    break;
-            }
-
-            if (failure) {
-                etiLog.level(alert) <<
-                    "Received Async UHD Message '" <<
-                    uhd_async_message << "' at time " <<
-                    md.time_spec.get_real_secs();
-
-            }
-        }
-
-        auto time_now = std::chrono::steady_clock::now();
-        if (last_print_time + std::chrono::seconds(1) < time_now) {
-            const double usrp_time =
-                myUsrp->get_time_now().get_real_secs();
-
-            if ( (num_underflows > num_underflows_previous) or
-                 (num_late_packets > num_late_packets_previous)) {
-                etiLog.log(info,
-                        "OutputUHD status (usrp time: %f): "
-                        "%d underruns and %d late packets since last status.\n",
-                        usrp_time,
-                        num_underflows, num_late_packets);
-            }
-
-            num_underflows_previous = num_underflows;
-            num_late_packets_previous = num_late_packets;
-
-            last_print_time = time_now;
-        }
-    }
-}
-
-// =======================================
-// Remote Control for UHD
-// =======================================
-void OutputUHD::set_parameter(const string& parameter, const string& value)
-{
-    stringstream ss(value);
-    ss.exceptions ( stringstream::failbit | stringstream::badbit );
-
-    if (parameter == "txgain") {
-        ss >> myConf.txgain;
-        myUsrp->set_tx_gain(myConf.txgain);
-    }
-    else if (parameter == "rxgain") {
-        ss >> myConf.rxgain;
-        myUsrp->set_rx_gain(myConf.rxgain);
-    }
-    else if (parameter == "freq") {
-        ss >> myConf.frequency;
-        tune_usrp_to(myUsrp, myConf.lo_offset, myConf.frequency);
-        myConf.frequency = myUsrp->get_tx_freq();
-    }
-    else if (parameter == "muting") {
-        ss >> myConf.muting;
-    }
-    else if (parameter == "staticdelay") {
-        int64_t adjust;
-        ss >> adjust;
-        if (adjust > (myTFDurationMs * 1000))
-        { // reset static delay for values outside range
-            myConf.staticDelayUs = 0;
-        }
-        else
-        { // the new adjust value is added to the existing delay and the result
-            // is wrapped around at TF duration
-            int newStaticDelayUs = myConf.staticDelayUs + adjust;
-            if (newStaticDelayUs > (myTFDurationMs * 1000))
-                myConf.staticDelayUs = newStaticDelayUs - (myTFDurationMs * 1000);
-            else if (newStaticDelayUs < 0)
-                myConf.staticDelayUs = newStaticDelayUs + (myTFDurationMs * 1000);
-            else
-                myConf.staticDelayUs = newStaticDelayUs;
-        }
-    }
-    else if (parameter == "underruns" or
-            parameter == "latepackets" or
-            parameter == "frames") {
-        throw ParameterError("Parameter " + parameter + " is read-only.");
-    }
-    else {
-        stringstream ss_err;
-        ss_err << "Parameter '" << parameter
-            << "' is not exported by controllable " << get_rc_name();
-        throw ParameterError(ss_err.str());
-    }
-}
-
-const string OutputUHD::get_parameter(const string& parameter) const
-{
-    stringstream ss;
-    if (parameter == "txgain") {
-        ss << myConf.txgain;
-    }
-    else if (parameter == "rxgain") {
-        ss << myConf.rxgain;
-    }
-    else if (parameter == "freq") {
-        ss << myConf.frequency;
-    }
-    else if (parameter == "muting") {
-        ss << myConf.muting;
-    }
-    else if (parameter == "staticdelay") {
-        ss << myConf.staticDelayUs;
-    }
-    else if (parameter == "underruns") {
-        ss << num_underflows;
-    }
-    else if (parameter == "latepackets") {
-        ss << num_late_packets;
-    }
-    else if (parameter == "frames") {
-        ss << num_frames_modulated;
-    }
-    else {
-        ss << "Parameter '" << parameter <<
-            "' is not exported by controllable " << get_rc_name();
-        throw ParameterError(ss.str());
-    }
-    return ss.str();
-}
-
-#endif // HAVE_OUTPUT_UHD
-
diff --git a/src/OutputUHD.h b/src/OutputUHD.h
deleted file mode 100644
index 9213183..0000000
--- a/src/OutputUHD.h
+++ /dev/null
@@ -1,250 +0,0 @@
-/*
-   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
-   Queen in Right of Canada (Communications Research Center Canada)
-
-   Copyright (C) 2017
-   Matthias P. Braendli, matthias.braendli@mpb.li
-
-    http://opendigitalradio.org
-
-DESCRIPTION:
-   It is an output driver for the USRP family of devices, and uses the UHD
-   library. This version is multi-threaded. A separate thread sends the data to
-   the device.
-
-   Data between the modulator and the UHD thread are exchanged through a
-   threadsafe queue.
-*/
-
-/*
-   This file is part of ODR-DabMod.
-
-   ODR-DabMod is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as
-   published by the Free Software Foundation, either version 3 of the
-   License, or (at your option) any later version.
-
-   ODR-DabMod is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#pragma once
-
-#ifdef HAVE_CONFIG_H
-#   include <config.h>
-#endif
-
-#ifdef HAVE_OUTPUT_UHD
-
-#include <uhd/utils/thread_priority.hpp>
-#include <uhd/utils/safe_main.hpp>
-#include <uhd/usrp/multi_usrp.hpp>
-#include <boost/thread.hpp>
-#include <deque>
-#include <chrono>
-#include <memory>
-#include <string>
-#include <atomic>
-
-#include "Log.h"
-#include "ModPlugin.h"
-#include "EtiReader.h"
-#include "TimestampDecoder.h"
-#include "RemoteControl.h"
-#include "ThreadsafeQueue.h"
-#include "OutputUHDFeedback.h"
-
-#include <stdio.h>
-#include <sys/types.h>
-
-//#define MDEBUG(fmt, args...) fprintf(LOG, fmt , ## args)
-#define MDEBUG(fmt, args...)
-
-// If the timestamp is further in the future than
-// 100 seconds, abort
-#define TIMESTAMP_ABORT_FUTURE 100
-
-// Add a delay to increase buffers when
-// frames are too far in the future
-#define TIMESTAMP_MARGIN_FUTURE 0.5
-
-typedef std::complex<float> complexf;
-
-// Each frame contains one OFDM frame, and its
-// associated timestamp
-struct UHDWorkerFrameData {
-    // Buffer holding frame data
-    std::vector<uint8_t> buf;
-
-    // A full timestamp contains a TIST according to standard
-    // and time information within MNSC with tx_second.
-    struct frame_timestamp ts;
-};
-
-enum refclk_lock_loss_behaviour_t { CRASH, IGNORE };
-
-/* This structure is used as initial configuration for OutputUHD.
- * It must also contain all remote-controllable settings, otherwise
- * they will get lost on a modulator restart. */
-struct OutputUHDConfig {
-    std::string device;
-    std::string usrpType; // e.g. b100, b200, usrp2
-
-    // The USRP1 can accept two daughterboards
-    std::string subDevice; // e.g. A:0
-
-    long masterClockRate = 32768000;
-    unsigned sampleRate = 2048000;
-    double frequency = 0.0;
-    double lo_offset = 0.0;
-    double txgain = 0.0;
-    double rxgain = 0.0;
-    bool enableSync = false;
-
-    // When working with timestamps, mute the frames that
-    // do not have a timestamp
-    bool muteNoTimestamps = false;
-    unsigned dabMode = 0;
-    unsigned maxGPSHoldoverTime = 0;
-
-    /* allowed values : auto, int, sma, mimo */
-    std::string refclk_src;
-
-    /* allowed values : int, sma, mimo */
-    std::string pps_src;
-
-    /* allowed values : pos, neg */
-    std::string pps_polarity;
-
-    /* What to do when the reference clock PLL loses lock */
-    refclk_lock_loss_behaviour_t refclk_lock_loss_behaviour;
-
-    // muting can only be changed using the remote control
-    bool muting = false;
-
-    // static delay in microseconds
-    int staticDelayUs = 0;
-
-    // TCP port on which to serve TX and RX samples for the
-    // digital pre distortion learning tool
-    uint16_t dpdFeedbackServerPort = 0;
-};
-
-class OutputUHD: public ModOutput, public RemoteControllable {
-    public:
-        OutputUHD(OutputUHDConfig& config);
-        OutputUHD(const OutputUHD& other) = delete;
-        OutputUHD operator=(const OutputUHD& other) = delete;
-        ~OutputUHD();
-
-        int process(Buffer* dataIn);
-
-        const char* name() { return "OutputUHD"; }
-
-        void setETISource(EtiSource *etiSource);
-
-        /*********** REMOTE CONTROL ***************/
-
-        /* Base function to set parameters. */
-        virtual void set_parameter(const std::string& parameter,
-                const std::string& value);
-
-        /* Getting a parameter always returns a string. */
-        virtual const std::string get_parameter(
-                const std::string& parameter) const;
-
-    protected:
-        EtiSource *myEtiSource = nullptr;
-        OutputUHDConfig& myConf;
-        uhd::usrp::multi_usrp::sptr myUsrp;
-        std::shared_ptr<boost::barrier> mySyncBarrier;
-        bool first_run = true;
-        bool gps_fix_verified = false;
-        std::shared_ptr<OutputUHDFeedback> uhdFeedback;
-
-    private:
-        // Resize the internal delay buffer according to the dabMode and
-        // the sample rate.
-        void SetDelayBuffer(unsigned int dabMode);
-
-        // data
-        // The remote-controllable static delay is in the OutputUHDConfig
-        int myTFDurationMs; // TF duration in milliseconds
-        std::vector<complexf> myDelayBuf;
-        size_t lastLen = 0;
-
-        // GPS Fix check variables
-        int num_checks_without_gps_fix = 1;
-        struct timespec first_gps_fix_check;
-        struct timespec last_gps_fix_check;
-        struct timespec time_last_frame;
-        boost::packaged_task<bool> gps_fix_pt;
-        boost::unique_future<bool> gps_fix_future;
-        boost::thread gps_fix_task;
-
-        // Wait time in seconds to get fix
-        static const int initial_gps_fix_wait = 180;
-
-        // Interval for checking the GPS at runtime
-        static constexpr double gps_fix_check_interval = 10.0; // seconds
-
-        // Asynchronous message statistics
-        size_t num_underflows = 0;
-        size_t num_late_packets = 0;
-        size_t num_underflows_previous = 0;
-        size_t num_late_packets_previous = 0;
-
-        size_t num_frames_modulated = 0;
-
-        uhd::tx_metadata_t md;
-        bool     last_tx_time_initialised = false;
-        uint32_t last_tx_second = 0;
-        uint32_t last_tx_pps = 0;
-
-        // Used to print statistics once a second
-        std::chrono::steady_clock::time_point last_print_time;
-
-        bool sync_and_ts_valid = false;
-
-        ThreadsafeQueue<UHDWorkerFrameData> m_frames;
-
-        // Returns true if we want to verify loss of refclk
-        bool refclk_loss_needs_check(void) const;
-        bool suppress_refclk_loss_check = false;
-
-        // Returns true if we want to check for the gps_timelock sensor
-        bool gpsfix_needs_check(void) const;
-
-        // Return true if the gpsdo is from ettus, false if it is the ODR
-        // LEA-M8F board is used
-        bool gpsdo_is_ettus(void) const;
-
-        std::atomic<bool> running;
-        boost::thread uhd_thread;
-        boost::thread async_rx_thread;
-        void stop_threads(void);
-
-        uhd::tx_streamer::sptr myTxStream;
-
-        // The worker thread decouples the modulator from UHD
-        void workerthread();
-        void handle_frame(const struct UHDWorkerFrameData *frame);
-        void tx_frame(const struct UHDWorkerFrameData *frame, bool ts_update);
-
-        // Poll asynchronous metadata from UHD
-        void print_async_thread(void);
-
-        void check_gps();
-
-        void set_usrp_time();
-
-        void initial_gps_check();
-};
-
-#endif // HAVE_OUTPUT_UHD
-
diff --git a/src/OutputZeroMQ.cpp b/src/OutputZeroMQ.cpp
index 93fe3c0..69f4aa1 100644
--- a/src/OutputZeroMQ.cpp
+++ b/src/OutputZeroMQ.cpp
@@ -32,8 +32,8 @@
 
 #if defined(HAVE_ZEROMQ)
 
-OutputZeroMQ::OutputZeroMQ(std::string endpoint, int type, Buffer* dataOut)
-    : ModOutput(),
+OutputZeroMQ::OutputZeroMQ(std::string endpoint, int type, Buffer* dataOut) :
+    ModOutput(),
     m_type(type),
     m_zmq_context(1),
     m_zmq_sock(m_zmq_context, type),
@@ -59,11 +59,6 @@ OutputZeroMQ::OutputZeroMQ(std::string endpoint, int type, Buffer* dataOut)
     m_zmq_sock.bind(m_endpoint.c_str());
 }
 
-OutputZeroMQ::~OutputZeroMQ()
-{
-    PDEBUG("OutputZeroMQ::~OutputZeroMQ() @ %p\n", this);
-}
-
 int OutputZeroMQ::process(Buffer* dataIn)
 {
     PDEBUG("OutputZeroMQ::process"
diff --git a/src/OutputZeroMQ.h b/src/OutputZeroMQ.h
index 3107225..be2451b 100644
--- a/src/OutputZeroMQ.h
+++ b/src/OutputZeroMQ.h
@@ -38,10 +38,9 @@
 class OutputZeroMQ : public ModOutput
 {
     public:
-        OutputZeroMQ(std::string endpoint, int type, Buffer* dataOut = NULL);
-        virtual ~OutputZeroMQ();
-        virtual int process(Buffer* dataIn);
-        const char* name() { return m_name.c_str(); }
+        OutputZeroMQ(std::string endpoint, int type, Buffer* dataOut = nullptr);
+        virtual int process(Buffer* dataIn) override;
+        const char* name() override { return m_name.c_str(); }
 
     protected:
         int m_type;                   // zmq socket type
diff --git a/src/Resampler.h b/src/Resampler.h
index d9d9d89..ed94a8c 100644
--- a/src/Resampler.h
+++ b/src/Resampler.h
@@ -59,7 +59,6 @@ protected:
     FFT_PLAN myFftPlan2;
     size_t L;
     size_t M;
-    size_t K;
     size_t myFftSizeIn;
     size_t myFftSizeOut;
     FFT_TYPE* myFftIn;
diff --git a/src/Socket.h b/src/Socket.h
index 39554ca..392e758 100644
--- a/src/Socket.h
+++ b/src/Socket.h
@@ -49,6 +49,14 @@ class TCPSocket {
             if ((m_sock = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
                 throw std::runtime_error("Can't create TCP socket");
             }
+
+#if defined(HAVE_SO_NOSIGPIPE)
+            int val = 1;
+            if (setsockopt(m_sock, SOL_SOCKET, SO_NOSIGPIPE,
+                        &val, sizeof(val)) < 0) {
+                throw std::runtime_error("Can't set SO_NOSIGPIPE");
+            }
+#endif
         }
 
         ~TCPSocket() {
@@ -89,11 +97,12 @@ class TCPSocket {
             addr.sin_addr.s_addr = htonl(INADDR_ANY);
 
             const int reuse = 1;
-            if (setsockopt(m_sock, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0) {
+            if (setsockopt(m_sock, SOL_SOCKET, SO_REUSEADDR,
+                        &reuse, sizeof(reuse)) < 0) {
                 throw std::runtime_error("Can't reuse address for TCP socket");
             }
 
-            if (bind(m_sock, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
+            if (::bind(m_sock, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
                 close();
                 throw std::runtime_error("Can't bind TCP socket");
             }
@@ -138,8 +147,16 @@ class TCPSocket {
         {
             uint8_t *buf = (uint8_t*)buffer;
             while (buflen > 0) {
-                // Set MSG_NOSIGNAL to avoid that this thread gets a SIGPIPE
-                ssize_t sent = send(m_sock, buf, buflen, MSG_NOSIGNAL);
+                /* On Linux, the MSG_NOSIGNAL flag ensures that the process
+                 * would not receive a SIGPIPE and die.
+                 * Other systems have SO_NOSIGPIPE set on the socket for the
+                 * same effect. */
+#if defined(HAVE_MSG_NOSIGNAL)
+                const int flags = MSG_NOSIGNAL;
+#else
+                const int flags = 0;
+#endif
+                ssize_t sent = ::send(m_sock, buf, buflen, flags);
                 if (sent < 0) {
                     return -1;
                 }
diff --git a/src/TII.cpp b/src/TII.cpp
index 89cd6d0..3c5823b 100644
--- a/src/TII.cpp
+++ b/src/TII.cpp
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -187,7 +187,7 @@ int TII::process(Buffer* dataIn, Buffer* dataOut)
     memset(dataOut->getData(), 0,  dataOut->getLength());
 
     if (m_conf.enable and m_insert) {
-        boost::mutex::scoped_lock lock(m_enabled_carriers_mutex);
+        std::lock_guard<std::mutex> lock(m_enabled_carriers_mutex);
         complexf* in = reinterpret_cast<complexf*>(dataIn->getData());
         complexf* out = reinterpret_cast<complexf*>(dataOut->getData());
 
@@ -231,7 +231,7 @@ void TII::enable_carrier(int k) {
 void TII::prepare_pattern() {
     int comb = m_conf.comb; // Convert from unsigned to signed
 
-    boost::mutex::scoped_lock lock(m_enabled_carriers_mutex);
+    std::lock_guard<std::mutex> lock(m_enabled_carriers_mutex);
 
     // Clear previous pattern
     for (size_t i = 0; i < m_enabled_carriers.size(); i++) {
diff --git a/src/TII.h b/src/TII.h
index b0ffdb3..b86dbbf 100644
--- a/src/TII.h
+++ b/src/TII.h
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
    the Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -35,8 +35,8 @@
 #include "ModPlugin.h"
 #include "RemoteControl.h"
 
-#include <boost/thread.hpp>
-#include <sys/types.h>
+#include <cstddef>
+#include <thread>
 #include <complex>
 #include <vector>
 #include <string>
@@ -118,7 +118,7 @@ class TII : public ModCodec, public RemoteControllable
 
         // m_enabled_carriers is read by modulator thread, and written
         // to by RC thread.
-        mutable boost::mutex m_enabled_carriers_mutex;
+        mutable std::mutex m_enabled_carriers_mutex;
 
         // m_enabled_carriers is true only for the first carrier in the
         // active pair
diff --git a/src/TimestampDecoder.cpp b/src/TimestampDecoder.cpp
index 26deb60..b942c37 100644
--- a/src/TimestampDecoder.cpp
+++ b/src/TimestampDecoder.cpp
@@ -24,93 +24,61 @@
    along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <queue>
 #include <iostream>
 #include <fstream>
 #include <string>
-#include <sys/types.h>
 #include "PcDebug.h"
 #include "TimestampDecoder.h"
-#include "Eti.h"
 #include "Log.h"
+#include "Eti.h"
 
 //#define MDEBUG(fmt, args...) fprintf (LOG, "*****" fmt , ## args)
 #define MDEBUG(fmt, args...) PDEBUG(fmt, ## args)
 
+TimestampDecoder::TimestampDecoder(double& offset_s) :
+        RemoteControllable("tist"),
+        timestamp_offset(offset_s)
+{
+    // Properly initialise temp_time
+    memset(&temp_time, 0, sizeof(temp_time));
+    const time_t timep = 0;
+    gmtime_r(&timep, &temp_time);
+
+    RC_ADD_PARAMETER(offset, "TIST offset [s]");
+    RC_ADD_PARAMETER(timestamp, "FCT and timestamp [s]");
 
-void TimestampDecoder::calculateTimestamp(frame_timestamp& ts)
+    etiLog.level(info) << "Setting up timestamp decoder with " <<
+        timestamp_offset << " offset";
+}
+
+std::shared_ptr<frame_timestamp> TimestampDecoder::getTimestamp()
 {
-    std::shared_ptr<frame_timestamp> ts_queued =
-        std::make_shared<frame_timestamp>();
+    auto ts = std::make_shared<frame_timestamp>();
 
-    /* Push new timestamp into queue */
-    ts_queued->timestamp_valid = full_timestamp_received;
-    ts_queued->timestamp_sec = time_secs;
-    ts_queued->timestamp_pps = time_pps;
-    ts_queued->fct = latestFCT;
+    ts->timestamp_valid = full_timestamp_received;
+    ts->timestamp_sec = time_secs;
+    ts->timestamp_pps = time_pps;
+    ts->fct = latestFCT;
+    ts->fp = latestFP;
 
-    ts_queued->timestamp_refresh = offset_changed;
+    ts->timestamp_refresh = offset_changed;
     offset_changed = false;
 
     MDEBUG("time_secs=%d, time_pps=%f\n", time_secs,
             (double)time_pps / 16384000.0);
-    *ts_queued += timestamp_offset;
-
-    queue_timestamps.push(ts_queued);
-
-    /* Here, the queue size is one more than the pipeline delay, because
-     * we've just added a new element in the queue.
-     *
-     * Therefore, use <= and not < for comparison
-     */
-    if (queue_timestamps.size() <= m_tist_delay_stages) {
-        //fprintf(stderr, "* %zu %u ", queue_timestamps.size(), m_tist_delay_stages);
-        /* Return invalid timestamp until the queue is full */
-        ts.timestamp_valid = false;
-        ts.timestamp_sec = 0;
-        ts.timestamp_pps = 0;
-        ts.timestamp_refresh = false;
-        ts.fct = -1;
-    }
-    else {
-        //fprintf(stderr, ". %zu ", queue_timestamps.size());
-        /* Return timestamp from queue */
-        ts_queued = queue_timestamps.front();
-        queue_timestamps.pop();
-        /*fprintf(stderr, "ts_queued v:%d, sec:%d, pps:%f, ref:%d\n",
-                ts_queued->timestamp_valid,
-                ts_queued->timestamp_sec,
-                ts_queued->timestamp_pps_offset,
-                ts_queued->timestamp_refresh);*/
-        ts = *ts_queued;
-        /*fprintf(stderr, "ts v:%d, sec:%d, pps:%f, ref:%d\n\n",
-                ts.timestamp_valid,
-                ts.timestamp_sec,
-                ts.timestamp_pps_offset,
-                ts.timestamp_refresh);*/
-    }
-
-    MDEBUG("Timestamp queue size %zu, delay_calc %u\n",
-            queue_timestamps.size(),
-            m_tist_delay_stages);
-
-    if (queue_timestamps.size() > m_tist_delay_stages) {
-        etiLog.level(error) << "Error: Timestamp queue is too large : size " <<
-            queue_timestamps.size() << "! This should not happen !";
-    }
+    *ts += timestamp_offset;
 
-    //ts.print("calc2 ");
+    return ts;
 }
 
-void TimestampDecoder::pushMNSCData(int framephase, uint16_t mnsc)
+void TimestampDecoder::pushMNSCData(uint8_t framephase, uint16_t mnsc)
 {
     struct eti_MNSC_TIME_0 *mnsc0;
     struct eti_MNSC_TIME_1 *mnsc1;
     struct eti_MNSC_TIME_2 *mnsc2;
     struct eti_MNSC_TIME_3 *mnsc3;
 
-    switch (framephase)
-    {
+    switch (framephase) {
         case 0:
             mnsc0 = (struct eti_MNSC_TIME_0*)&mnsc;
             enableDecode = (mnsc0->type == 0) &&
@@ -126,10 +94,10 @@ void TimestampDecoder::pushMNSCData(int framephase, uint16_t mnsc)
             temp_time.tm_sec = mnsc1->second_tens * 10 + mnsc1->second_unit;
             temp_time.tm_min = mnsc1->minute_tens * 10 + mnsc1->minute_unit;
 
-            if (!mnsc1->sync_to_frame)
-            {
+            if (!mnsc1->sync_to_frame) {
                 enableDecode = false;
-                PDEBUG("TimestampDecoder: MNSC time info is not synchronised to frame\n");
+                PDEBUG("TimestampDecoder: "
+                        "MNSC time info is not synchronised to frame\n");
             }
 
             break;
@@ -145,9 +113,7 @@ void TimestampDecoder::pushMNSCData(int framephase, uint16_t mnsc)
             temp_time.tm_mon = (mnsc3->month_tens * 10 + mnsc3->month_unit) - 1;
             temp_time.tm_year = (mnsc3->year_tens * 10 + mnsc3->year_unit) + 100;
 
-            if (enableDecode)
-            {
-                full_timestamp_received = true;
+            if (enableDecode) {
                 updateTimestampSeconds(mktime(&temp_time));
             }
             break;
@@ -160,15 +126,14 @@ void TimestampDecoder::pushMNSCData(int framephase, uint16_t mnsc)
 
 void TimestampDecoder::updateTimestampSeconds(uint32_t secs)
 {
-    if (inhibit_second_update > 0)
-    {
+    if (inhibit_second_update > 0) {
         MDEBUG("TimestampDecoder::updateTimestampSeconds(%d) inhibit\n", secs);
         inhibit_second_update--;
     }
-    else
-    {
+    else {
         MDEBUG("TimestampDecoder::updateTimestampSeconds(%d) apply\n", secs);
         time_secs = secs;
+        full_timestamp_received = true;
     }
 }
 
@@ -176,8 +141,7 @@ void TimestampDecoder::updateTimestampPPS(uint32_t pps)
 {
     MDEBUG("TimestampDecoder::updateTimestampPPS(%f)\n", (double)pps / 16384000.0);
 
-    if (time_pps > pps) // Second boundary crossed
-    {
+    if (time_pps > pps) { // Second boundary crossed
         MDEBUG("TimestampDecoder::updateTimestampPPS crossed second\n");
 
         // The second for the next eight frames will not
@@ -190,7 +154,7 @@ void TimestampDecoder::updateTimestampPPS(uint32_t pps)
 }
 
 void TimestampDecoder::updateTimestampEti(
-        int framephase,
+        uint8_t framephase,
         uint16_t mnsc,
         uint32_t pps, // In units of 1/16384000 s
         int32_t fct)
@@ -198,16 +162,19 @@ void TimestampDecoder::updateTimestampEti(
     updateTimestampPPS(pps);
     pushMNSCData(framephase, mnsc);
     latestFCT = fct;
+    latestFP = framephase;
 }
 
 void TimestampDecoder::updateTimestampEdi(
         uint32_t seconds_utc,
         uint32_t pps, // In units of 1/16384000 s
-        int32_t fct)
+        int32_t fct,
+        uint8_t framephase)
 {
     time_secs = seconds_utc;
     time_pps  = pps;
     latestFCT = fct;
+    latestFP = framephase;
     full_timestamp_received = true;
 }
 
diff --git a/src/TimestampDecoder.h b/src/TimestampDecoder.h
index db8f816..33d9992 100644
--- a/src/TimestampDecoder.h
+++ b/src/TimestampDecoder.h
@@ -2,7 +2,7 @@
    Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
    Queen in Right of Canada (Communications Research Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -26,41 +26,24 @@
 
 #pragma once
 
-#include <queue>
+#include <cstdint>
 #include <memory>
 #include <string>
-#include <time.h>
 #include <math.h>
 #include <stdio.h>
-#include "Eti.h"
-#include "Log.h"
 #include "RemoteControl.h"
 
 struct frame_timestamp
 {
     // Which frame count does this timestamp apply to
     int32_t fct;
+    uint8_t fp; // Frame Phase
 
     uint32_t timestamp_sec;
     uint32_t timestamp_pps; // In units of 1/16384000 s
-    bool timestamp_valid;
+    bool timestamp_valid = false;
     bool timestamp_refresh;
 
-    frame_timestamp() = default;
-    frame_timestamp(const frame_timestamp& other) = default;
-    frame_timestamp& operator=(const frame_timestamp &rhs)
-    {
-        if (this != &rhs) {
-            this->timestamp_sec = rhs.timestamp_sec;
-            this->timestamp_pps = rhs.timestamp_pps;
-            this->timestamp_valid = rhs.timestamp_valid;
-            this->timestamp_refresh = rhs.timestamp_refresh;
-            this->fct = rhs.fct;
-        }
-
-        return *this;
-    }
-
     frame_timestamp& operator+=(const double& diff)
     {
         double offset_pps, offset_secs;
@@ -69,16 +52,14 @@ struct frame_timestamp
         this->timestamp_sec += lrintf(offset_secs);
         this->timestamp_pps += lrintf(offset_pps * 16384000.0);
 
-        while (this->timestamp_pps >= 16384000)
-        {
+        while (this->timestamp_pps >= 16384000) {
             this->timestamp_pps -= 16384000;
             this->timestamp_sec += 1;
-        };
+        }
         return *this;
     }
 
-    const frame_timestamp operator+(const double diff)
-    {
+    const frame_timestamp operator+(const double diff) {
         frame_timestamp ts = *this;
         ts += diff;
         return ts;
@@ -88,8 +69,19 @@ struct frame_timestamp
         return timestamp_pps / 16384000.0;
     }
 
-    void print(const char* t)
-    {
+    double get_real_secs() const {
+        double t = timestamp_sec;
+        t += pps_offset();
+        return t;
+    }
+
+    long long int get_ns() const {
+        long long int ns = timestamp_sec * 1000000000ull;
+        ns += llrint((double)timestamp_pps / 0.016384);
+        return ns;
+    }
+
+    void print(const char* t) const {
         fprintf(stderr,
                 "%s <frame_timestamp(%s, %d, %.9f, %d)>\n",
                 t, this->timestamp_valid ? "valid" : "invalid",
@@ -103,49 +95,16 @@ struct frame_timestamp
 class TimestampDecoder : public RemoteControllable
 {
     public:
-        TimestampDecoder(
-                /* The modulator adds this offset to the TIST to define time of
-                 * frame transmission
-                 */
-                double& offset_s,
-
-                /* Specifies by how many stages the timestamp must be delayed.
-                 * (e.g. The FIRFilter is pipelined, therefore we must increase
-                 * tist_delay_stages by one if the filter is used
-                 */
-                unsigned tist_delay_stages) :
-            RemoteControllable("tist"),
-            timestamp_offset(offset_s)
-        {
-            m_tist_delay_stages = tist_delay_stages;
-            inhibit_second_update = 0;
-            time_pps = 0.0;
-            time_secs = 0;
-            latestFCT = 0;
-            enableDecode = false;
-            full_timestamp_received = false;
-
-            // Properly initialise temp_time
-            memset(&temp_time, 0, sizeof(temp_time));
-            const time_t timep = 0;
-            gmtime_r(&timep, &temp_time);
-
-            offset_changed = false;
-
-            RC_ADD_PARAMETER(offset, "TIST offset [s]");
-            RC_ADD_PARAMETER(timestamp, "FCT and timestamp [s]");
-
-            etiLog.level(info) << "Setting up timestamp decoder with " <<
-                timestamp_offset << " offset";
-
-        };
-
-        /* Calculate the timestamp for the current frame. */
-        void calculateTimestamp(frame_timestamp& ts);
+        /* offset_s: The modulator adds this offset to the TIST to define time of
+         * frame transmission
+         */
+        TimestampDecoder(double& offset_s);
+
+        std::shared_ptr<frame_timestamp> getTimestamp(void);
 
         /* Update timestamp data from ETI */
         void updateTimestampEti(
-                int framephase,
+                uint8_t framephase,
                 uint16_t mnsc,
                 uint32_t pps, // In units of 1/16384000 s
                 int32_t fct);
@@ -154,7 +113,8 @@ class TimestampDecoder : public RemoteControllable
         void updateTimestampEdi(
                 uint32_t seconds_utc,
                 uint32_t pps, // In units of 1/16384000 s
-                int32_t fct);
+                int32_t fct,
+                uint8_t framephase);
 
         /*********** REMOTE CONTROL ***************/
 
@@ -171,7 +131,7 @@ class TimestampDecoder : public RemoteControllable
 
     protected:
         /* Push a new MNSC field into the decoder */
-        void pushMNSCData(int framephase, uint16_t mnsc);
+        void pushMNSCData(uint8_t framephase, uint16_t mnsc);
 
         /* Each frame contains the TIST field with the PPS offset.
          * For each frame, this function must be called to update
@@ -191,28 +151,20 @@ class TimestampDecoder : public RemoteControllable
         void updateTimestampSeconds(uint32_t secs);
 
         struct tm temp_time;
-        uint32_t time_secs;
-        int32_t latestFCT;
-        uint32_t time_pps;
+        uint32_t time_secs = 0;
+        int32_t latestFCT = 0;
+        uint32_t latestFP = 0;
+        uint32_t time_pps = 0;
         double& timestamp_offset;
-        unsigned m_tist_delay_stages;
-        int inhibit_second_update;
-        bool offset_changed;
+        int inhibit_second_update = 0;
+        bool offset_changed = false;
 
         /* When the type or identifier don't match, the decoder must
          * be disabled
          */
-        bool enableDecode;
+        bool enableDecode = false;
 
         /* Disable timstamps until full time has been received */
-        bool full_timestamp_received;
-
-        /* when pipelining, we must shift the calculated timestamps
-         * through this queue. Otherwise, it would not be possible to
-         * synchronise two modulators if only one uses (for instance) the
-         * FIRFilter (1 stage pipeline)
-         */
-        std::queue<std::shared_ptr<frame_timestamp> > queue_timestamps;
-
+        bool full_timestamp_received = false;
 };
 
diff --git a/src/Utils.cpp b/src/Utils.cpp
index f423dc1..b4816d3 100644
--- a/src/Utils.cpp
+++ b/src/Utils.cpp
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -214,3 +214,17 @@ double parseChannel(const std::string& chan)
     }
     return freq;
 }
+
+std::chrono::milliseconds transmission_frame_duration(unsigned int dabmode)
+{
+    using namespace std::chrono;
+    switch (dabmode) {
+        case 1: return milliseconds(96);
+        case 2: return milliseconds(24);
+        case 3: return milliseconds(24);
+        case 4: return milliseconds(48);
+        default:
+            throw std::runtime_error("invalid DAB mode");
+    }
+}
+
diff --git a/src/Utils.h b/src/Utils.h
index 6a36baf..9e88488 100644
--- a/src/Utils.h
+++ b/src/Utils.h
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2017
+   Copyright (C) 2018
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -36,6 +36,7 @@
 #include <stdio.h>
 #include <time.h>
 #include <string>
+#include <chrono>
 
 void printUsage(const char* progName);
 
@@ -43,22 +44,6 @@ void printVersion(void);
 
 void printStartupInfo(void);
 
-inline long timespecdiff_us(struct timespec& oldTime, struct timespec& time)
-{
-    long tv_sec;
-    long tv_nsec;
-    if (time.tv_nsec < oldTime.tv_nsec) {
-        tv_sec = time.tv_sec - 1 - oldTime.tv_sec;
-        tv_nsec = 1000000000L + time.tv_nsec - oldTime.tv_nsec;
-    }
-    else {
-        tv_sec = time.tv_sec - oldTime.tv_sec;
-        tv_nsec = time.tv_nsec - oldTime.tv_nsec;
-    }
-
-    return tv_sec * 1000 + tv_nsec / 1000;
-}
-
 // Set SCHED_RR with priority prio (0=lowest)
 int set_realtime_prio(int prio);
 
@@ -68,3 +53,6 @@ void set_thread_name(const char *name);
 // Convert a channel like 10A to a frequency
 double parseChannel(const std::string& chan);
 
+// dabMode is either 1, 2, 3, 4, corresponding to TM I, TM II, TM III and TM IV.
+// throws a runtime_error if dabMode is not one of these values.
+std::chrono::milliseconds transmission_frame_duration(unsigned int dabmode);
diff --git a/src/OutputUHDFeedback.cpp b/src/output/Feedback.cpp
index 68783f2..f0bbd98 100644
--- a/src/OutputUHDFeedback.cpp
+++ b/src/output/Feedback.cpp
@@ -34,41 +34,41 @@ DESCRIPTION:
 #   include <config.h>
 #endif
 
-#ifdef HAVE_OUTPUT_UHD
-
 #include <vector>
 #include <complex>
 #include <cstring>
-#include <uhd/types/stream_cmd.hpp>
 #include <sys/socket.h>
 #include <errno.h>
 #include <poll.h>
 #include <boost/date_time/posix_time/posix_time.hpp>
-#include "OutputUHDFeedback.h"
+#include "output/Feedback.h"
 #include "Utils.h"
 #include "Socket.h"
 
 using namespace std;
-typedef std::complex<float> complexf;
 
-OutputUHDFeedback::OutputUHDFeedback(
-        uhd::usrp::multi_usrp::sptr usrp,
+namespace Output {
+
+DPDFeedbackServer::DPDFeedbackServer(
+        std::shared_ptr<SDRDevice> device,
         uint16_t port,
-        uint32_t sampleRate)
+        uint32_t sampleRate) :
+    m_port(port),
+    m_sampleRate(sampleRate),
+    m_device(device)
 {
-    m_port = port;
-    m_sampleRate = sampleRate;
-    m_usrp = usrp;
-
     if (m_port) {
         m_running.store(true);
 
-        rx_burst_thread = boost::thread(&OutputUHDFeedback::ReceiveBurstThread, this);
-        burst_tcp_thread = boost::thread(&OutputUHDFeedback::ServeFeedbackThread, this);
+        rx_burst_thread = boost::thread(
+                &DPDFeedbackServer::ReceiveBurstThread, this);
+
+        burst_tcp_thread = boost::thread(
+                &DPDFeedbackServer::ServeFeedbackThread, this);
     }
 }
 
-OutputUHDFeedback::~OutputUHDFeedback()
+DPDFeedbackServer::~DPDFeedbackServer()
 {
     m_running.store(false);
 
@@ -83,12 +83,12 @@ OutputUHDFeedback::~OutputUHDFeedback()
     }
 }
 
-void OutputUHDFeedback::set_tx_frame(
+void DPDFeedbackServer::set_tx_frame(
         const std::vector<uint8_t> &buf,
         const struct frame_timestamp &buf_ts)
 {
     if (not m_running) {
-        throw runtime_error("OutputUHDFeedback not running");
+        throw runtime_error("DPDFeedbackServer not running");
     }
 
     boost::mutex::scoped_lock lock(burstRequest.mutex);
@@ -131,13 +131,10 @@ void OutputUHDFeedback::set_tx_frame(
     }
 }
 
-void OutputUHDFeedback::ReceiveBurstThread()
+void DPDFeedbackServer::ReceiveBurstThread()
 {
     try {
-        set_thread_name("uhdreceiveburst");
-
-        uhd::stream_args_t stream_args("fc32"); //complex floats
-        auto rxStream = m_usrp->get_rx_stream(stream_args);
+        set_thread_name("dpdreceiveburst");
 
         while (m_running) {
             boost::mutex::scoped_lock lock(burstRequest.mutex);
@@ -148,43 +145,40 @@ void OutputUHDFeedback::ReceiveBurstThread()
 
             if (not m_running) break;
 
-            uhd::stream_cmd_t cmd(
-                    uhd::stream_cmd_t::stream_mode_t::STREAM_MODE_NUM_SAMPS_AND_DONE);
-            cmd.num_samps = burstRequest.num_samples;
-            cmd.stream_now = false;
+            const size_t num_samps = burstRequest.num_samples;
 
-            double pps = burstRequest.rx_pps / 16384000.0;
-            cmd.time_spec = uhd::time_spec_t(burstRequest.rx_second, pps);
+            frame_timestamp ts;
+            ts.timestamp_sec = burstRequest.rx_second;
+            ts.timestamp_pps = burstRequest.rx_pps;
+            ts.timestamp_valid = true;
 
             // We need to free the mutex while we recv(), because otherwise we block the
             // TX thread
             lock.unlock();
 
-            const double usrp_time = m_usrp->get_time_now().get_real_secs();
-            const double cmd_time = cmd.time_spec.get_real_secs();
-
-            rxStream->issue_stream_cmd(cmd);
+            const double device_time = m_device->get_real_secs();
+            const double cmd_time = ts.get_real_secs();
 
-            uhd::rx_metadata_t md;
-
-            std::vector<uint8_t> buf(cmd.num_samps * sizeof(complexf));
+            std::vector<uint8_t> buf(num_samps * sizeof(complexf));
 
             const double timeout = 60;
-            size_t samples_read = rxStream->recv(&buf[0], cmd.num_samps, md, timeout);
+            size_t samples_read = m_device->receive_frame(
+                    reinterpret_cast<complexf*>(buf.data()),
+                    num_samps, ts, timeout);
 
             lock.lock();
             burstRequest.rx_samples = std::move(buf);
             burstRequest.rx_samples.resize(samples_read * sizeof(complexf));
 
             // The recv might have happened at another time than requested
-            burstRequest.rx_second = md.time_spec.get_full_secs();
-            burstRequest.rx_pps = md.time_spec.get_frac_secs() * 16384000.0;
+            burstRequest.rx_second = ts.timestamp_sec;
+            burstRequest.rx_pps = ts.timestamp_pps;
 
             etiLog.level(debug) << "DPD: acquired " << samples_read <<
                 " RX feedback samples " <<
                 "at time " << burstRequest.tx_second << " + " <<
                 std::fixed << burstRequest.tx_pps / 16384000.0 <<
-                " Delta=" << cmd_time - usrp_time;
+                " Delta=" << cmd_time - device_time;
 
             burstRequest.state = BurstRequestState::Acquired;
 
@@ -205,7 +199,7 @@ void OutputUHDFeedback::ReceiveBurstThread()
     m_running.store(false);
 }
 
-void OutputUHDFeedback::ServeFeedback()
+void DPDFeedbackServer::ServeFeedback()
 {
     TCPSocket m_server_sock;
     m_server_sock.listen(m_port);
@@ -335,9 +329,9 @@ void OutputUHDFeedback::ServeFeedback()
     }
 }
 
-void OutputUHDFeedback::ServeFeedbackThread()
+void DPDFeedbackServer::ServeFeedbackThread()
 {
-    set_thread_name("uhdservefeedback");
+    set_thread_name("dpdfeedbackserver");
 
     while (m_running) {
         try {
@@ -359,4 +353,4 @@ void OutputUHDFeedback::ServeFeedbackThread()
     m_running.store(false);
 }
 
-#endif
+} // namespace Output
diff --git a/src/OutputUHDFeedback.h b/src/output/Feedback.h
index 80d287f..2cad508 100644
--- a/src/OutputUHDFeedback.h
+++ b/src/output/Feedback.h
@@ -36,11 +36,6 @@ DESCRIPTION:
 #   include <config.h>
 #endif
 
-#ifdef HAVE_OUTPUT_UHD
-
-#include <uhd/utils/thread_priority.hpp>
-#include <uhd/utils/safe_main.hpp>
-#include <uhd/usrp/multi_usrp.hpp>
 #include <boost/thread.hpp>
 #include <memory>
 #include <string>
@@ -48,6 +43,9 @@ DESCRIPTION:
 
 #include "Log.h"
 #include "TimestampDecoder.h"
+#include "output/SDRDevice.h"
+
+namespace Output {
 
 enum class BurstRequestState {
     None, // To pending request
@@ -56,7 +54,7 @@ enum class BurstRequestState {
     Acquired, // Both TX and RX frames are ready
 };
 
-struct UHDReceiveBurstRequest {
+struct FeedbackBurstRequest {
     // All fields in this struct are protected
     mutable boost::mutex mutex;
     boost::condition_variable mutex_notification;
@@ -83,21 +81,21 @@ struct UHDReceiveBurstRequest {
 };
 
 // Serve TX samples and RX feedback samples over a TCP connection
-class OutputUHDFeedback {
+class DPDFeedbackServer {
     public:
-        OutputUHDFeedback(
-                uhd::usrp::multi_usrp::sptr usrp,
-                uint16_t port,
+        DPDFeedbackServer(
+                std::shared_ptr<SDRDevice> device,
+                uint16_t port, // Set to 0 to disable the Feedbackserver
                 uint32_t sampleRate);
-        OutputUHDFeedback(const OutputUHDFeedback& other) = delete;
-        OutputUHDFeedback& operator=(const OutputUHDFeedback& other) = delete;
-        ~OutputUHDFeedback();
+        DPDFeedbackServer(const DPDFeedbackServer& other) = delete;
+        DPDFeedbackServer& operator=(const DPDFeedbackServer& other) = delete;
+        ~DPDFeedbackServer();
 
         void set_tx_frame(const std::vector<uint8_t> &buf,
                 const struct frame_timestamp& ts);
 
     private:
-        // Thread that reacts to burstRequests and receives from the USRP
+        // Thread that reacts to burstRequests and receives from the SDR device
         void ReceiveBurstThread(void);
 
         // Thread that listens for requests over TCP to get TX and RX feedback
@@ -107,13 +105,12 @@ class OutputUHDFeedback {
         boost::thread rx_burst_thread;
         boost::thread burst_tcp_thread;
 
-        UHDReceiveBurstRequest burstRequest;
+        FeedbackBurstRequest burstRequest;
 
         std::atomic_bool m_running;
         uint16_t m_port = 0;
         uint32_t m_sampleRate = 0;
-        uhd::usrp::multi_usrp::sptr m_usrp;
+        std::shared_ptr<SDRDevice> m_device;
 };
 
-
-#endif // HAVE_OUTPUT_UHD
+} // namespace Output
diff --git a/src/output/SDR.cpp b/src/output/SDR.cpp
new file mode 100644
index 0000000..34341bd
--- /dev/null
+++ b/src/output/SDR.cpp
@@ -0,0 +1,425 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+ */
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "output/SDR.h"
+
+#include "PcDebug.h"
+#include "Log.h"
+#include "RemoteControl.h"
+#include "Utils.h"
+
+#include <cmath>
+#include <iostream>
+#include <assert.h>
+#include <stdexcept>
+#include <stdio.h>
+#include <time.h>
+#include <errno.h>
+#include <unistd.h>
+#include <pthread.h>
+
+using namespace std;
+
+namespace Output {
+
+// Maximum number of frames that can wait in frames
+static constexpr size_t FRAMES_MAX_SIZE = 8;
+
+// If the timestamp is further in the future than
+// 100 seconds, abort
+static constexpr double TIMESTAMP_ABORT_FUTURE = 100;
+
+// Add a delay to increase buffers when
+// frames are too far in the future
+static constexpr double TIMESTAMP_MARGIN_FUTURE = 0.5;
+
+SDR::SDR(SDRDeviceConfig& config, std::shared_ptr<SDRDevice> device) :
+    ModOutput(), ModMetadata(), RemoteControllable("sdr"),
+    m_config(config),
+    m_device(device)
+{
+    // muting is remote-controllable
+    m_config.muting = false;
+
+    m_device_thread = std::thread(&SDR::process_thread_entry, this);
+
+    m_dpd_feedback_server = make_shared<DPDFeedbackServer>(
+            m_device,
+            m_config.dpdFeedbackServerPort,
+            m_config.sampleRate);
+}
+
+SDR::~SDR()
+{
+    m_running.store(false);
+
+    FrameData end_marker;
+    end_marker.buf.clear();
+    m_queue.push(end_marker);
+
+    if (m_device_thread.joinable()) {
+        m_device_thread.join();
+    }
+}
+
+int SDR::process(Buffer *dataIn)
+{
+    if (not m_running) {
+        throw std::runtime_error("SDR thread failed");
+    }
+
+    const uint8_t* pDataIn = (uint8_t*)dataIn->getData();
+    m_frame.resize(dataIn->getLength());
+    std::copy(pDataIn, pDataIn + dataIn->getLength(),
+            m_frame.begin());
+
+    // We will effectively transmit the frame once we got the metadata.
+
+    return dataIn->getLength();
+}
+
+meta_vec_t SDR::process_metadata(const meta_vec_t& metadataIn)
+{
+    if (m_device and m_running) {
+        FrameData frame;
+        frame.buf = std::move(m_frame);
+
+        if (metadataIn.empty()) {
+            etiLog.level(info) <<
+                "SDR output: dropping one frame with invalid FCT";
+        }
+        else {
+            /* In transmission modes where several ETI frames are needed to
+             * build one transmission frame (like in TM 1), we will have
+             * several entries in metadataIn. Take the first one, which
+             * comes from the earliest ETI frame.
+             * This behaviour is different to earlier versions of ODR-DabMod,
+             * which took the timestamp from the latest ETI frame.
+             */
+            frame.ts = *(metadataIn[0].ts);
+
+            // TODO check device running
+
+            try {
+                if (m_dpd_feedback_server) {
+                    m_dpd_feedback_server->set_tx_frame(frame.buf, frame.ts);
+                }
+            }
+            catch (const runtime_error& e) {
+                etiLog.level(warn) <<
+                    "SDR output: Feedback server failed, restarting...";
+
+                m_dpd_feedback_server = std::make_shared<DPDFeedbackServer>(
+                        m_device,
+                        m_config.dpdFeedbackServerPort,
+                        m_config.sampleRate);
+            }
+
+            size_t num_frames = m_queue.push_wait_if_full(frame,
+                    FRAMES_MAX_SIZE);
+            etiLog.log(trace, "SDR,push %zu", num_frames);
+        }
+    }
+    else {
+        // Ignore frame
+    }
+    return {};
+}
+
+
+void SDR::process_thread_entry()
+{
+    // Set thread priority to realtime
+    if (int ret = set_realtime_prio(1)) {
+        etiLog.level(error) << "Could not set priority for SDR device thread:" << ret;
+    }
+
+    set_thread_name("sdrdevice");
+
+    last_tx_time_initialised = false;
+
+    size_t last_num_underflows = 0;
+    size_t pop_prebuffering = FRAMES_MAX_SIZE;
+
+    m_running.store(true);
+
+    try {
+        while (m_running.load()) {
+            struct FrameData frame;
+            etiLog.log(trace, "SDR,wait");
+            m_queue.wait_and_pop(frame, pop_prebuffering);
+            etiLog.log(trace, "SDR,pop");
+
+            if (m_running.load() == false or frame.buf.empty()) {
+                break;
+            }
+
+            if (m_device) {
+                handle_frame(frame);
+
+                const auto rs = m_device->get_run_statistics();
+
+                /* Ensure we fill frames after every underrun and
+                 * at startup to reduce underrun likelihood. */
+                if (last_num_underflows < rs.num_underruns) {
+                    pop_prebuffering = FRAMES_MAX_SIZE;
+                }
+                else {
+                    pop_prebuffering = 1;
+                }
+
+                last_num_underflows = rs.num_underruns;
+            }
+        }
+    }
+    catch (const runtime_error& e) {
+        etiLog.level(error) << "SDR output thread caught runtime error: " << e.what();
+    }
+
+    m_running.store(false);
+}
+
+const char* SDR::name()
+{
+    if (m_device) {
+        m_name = "OutputSDR(";
+        m_name += m_device->device_name();
+        m_name += ")";
+    }
+    else {
+        m_name = "OutputSDR(<no device>)";
+    }
+    return m_name.c_str();
+}
+
+void SDR::sleep_through_frame()
+{
+    using namespace std::chrono;
+
+    const auto now = steady_clock::now();
+
+    if (not t_last_frame_initialised) {
+        t_last_frame = now;
+        t_last_frame_initialised = true;
+    }
+
+    const auto delta = now - t_last_frame;
+    const auto wait_time = transmission_frame_duration(m_config.dabMode);
+
+    if (wait_time > delta) {
+        this_thread::sleep_for(wait_time - delta);
+    }
+
+    t_last_frame += wait_time;
+}
+
+void SDR::handle_frame(struct FrameData& frame)
+{
+    // Assumes m_device is valid
+
+    constexpr double tx_timeout = 20.0;
+
+    if (not m_device->is_clk_source_ok()) {
+        sleep_through_frame();
+        return;
+    }
+
+    double device_time = m_device->get_real_secs();
+    const auto& time_spec = frame.ts;
+
+    if (m_config.enableSync and m_config.muteNoTimestamps and
+            not time_spec.timestamp_valid) {
+        sleep_through_frame();
+        etiLog.log(info,
+                "OutputSDR: Muting sample %d : no timestamp\n",
+                frame.ts.fct);
+        return;
+    }
+
+    if (m_config.enableSync and time_spec.timestamp_valid) {
+        // Tx time from MNSC and TIST
+        const uint32_t tx_second = frame.ts.timestamp_sec;
+        const uint32_t tx_pps    = frame.ts.timestamp_pps;
+
+        if (not frame.ts.timestamp_valid) {
+            /* We have not received a full timestamp through
+             * MNSC. We sleep through the frame.
+             */
+            etiLog.level(info) <<
+                "OutputSDR: Throwing sample " << frame.ts.fct <<
+                " away: incomplete timestamp " << tx_second <<
+                " / " << tx_pps;
+            return;
+        }
+
+        if (last_tx_time_initialised) {
+            const size_t sizeIn = frame.buf.size() / sizeof(complexf);
+            uint64_t increment = (uint64_t)sizeIn * 16384000ul /
+                                 (uint64_t)m_config.sampleRate;
+                                  // samps  * ticks/s  / (samps/s)
+                                  // (samps * ticks * s) / (s * samps)
+                                  // ticks
+
+            uint32_t expected_sec = last_tx_second + increment / 16384000ul;
+            uint32_t expected_pps = last_tx_pps + increment % 16384000ul;
+
+            while (expected_pps >= 16384000) {
+                expected_sec++;
+                expected_pps -= 16384000;
+            }
+
+            if (expected_sec != tx_second or expected_pps != tx_pps) {
+                etiLog.level(warn) << "OutputSDR: timestamp irregularity!" <<
+                    std::fixed <<
+                    " Expected " <<
+                    expected_sec << "+" << (double)expected_pps/16384000.0 <<
+                    "(" << expected_pps << ")" <<
+                    " Got " <<
+                    tx_second << "+" << (double)tx_pps/16384000.0 <<
+                    "(" << tx_pps << ")";
+
+                frame.ts.timestamp_refresh = true;
+            }
+        }
+
+        last_tx_second = tx_second;
+        last_tx_pps    = tx_pps;
+        last_tx_time_initialised = true;
+
+        const double pps_offset = tx_pps / 16384000.0;
+
+        etiLog.log(trace, "SDR,tist %f", time_spec.get_real_secs());
+
+        if (time_spec.get_real_secs() + tx_timeout < device_time) {
+            etiLog.level(warn) <<
+                "OutputSDR: Timestamp in the past! offset: " <<
+                std::fixed <<
+                time_spec.get_real_secs() - device_time <<
+                "  (" << device_time << ")"
+                " frame " << frame.ts.fct <<
+                ", tx_second " << tx_second <<
+                ", pps " << pps_offset;
+            return;
+        }
+
+        if (time_spec.get_real_secs() > device_time + TIMESTAMP_ABORT_FUTURE) {
+            etiLog.level(error) <<
+                "OutputSDR: Timestamp way too far in the future! offset: " <<
+                std::fixed <<
+                time_spec.get_real_secs() - device_time;
+            throw std::runtime_error("Timestamp error. Aborted.");
+        }
+    }
+
+    if (m_config.muting) {
+        etiLog.log(info,
+                "OutputSDR: Muting sample %d requested\n",
+                frame.ts.fct);
+        return;
+    }
+
+    m_device->transmit_frame(frame);
+}
+
+// =======================================
+// Remote Control
+// =======================================
+void SDR::set_parameter(const string& parameter, const string& value)
+{
+    stringstream ss(value);
+    ss.exceptions ( stringstream::failbit | stringstream::badbit );
+
+    if (parameter == "txgain") {
+        ss >> m_config.txgain;
+        m_device->set_txgain(m_config.txgain);
+    }
+    else if (parameter == "rxgain") {
+        ss >> m_config.rxgain;
+        m_device->set_rxgain(m_config.rxgain);
+    }
+    else if (parameter == "freq") {
+        ss >> m_config.frequency;
+        m_device->tune(m_config.lo_offset, m_config.frequency);
+        m_config.frequency = m_device->get_tx_freq();
+    }
+    else if (parameter == "muting") {
+        ss >> m_config.muting;
+    }
+    else if (parameter == "underruns" or
+             parameter == "latepackets" or
+             parameter == "frames") {
+        throw ParameterError("Parameter " + parameter + " is read-only.");
+    }
+    else {
+        stringstream ss_err;
+        ss_err << "Parameter '" << parameter
+            << "' is not exported by controllable " << get_rc_name();
+        throw ParameterError(ss_err.str());
+    }
+}
+
+const string SDR::get_parameter(const string& parameter) const
+{
+    stringstream ss;
+    if (parameter == "txgain") {
+        ss << m_config.txgain;
+    }
+    else if (parameter == "rxgain") {
+        ss << m_config.rxgain;
+    }
+    else if (parameter == "freq") {
+        ss << m_config.frequency;
+    }
+    else if (parameter == "muting") {
+        ss << m_config.muting;
+    }
+    else if (parameter == "underruns" or
+            parameter == "latepackets" or
+            parameter == "frames" ) {
+        if (not m_device) {
+            throw ParameterError("OutputSDR has no device");
+        }
+        const auto stat = m_device->get_run_statistics();
+
+        if (parameter == "underruns") {
+            ss << stat.num_underruns;
+        }
+        else if (parameter == "latepackets") {
+            ss << stat.num_late_packets;
+        }
+        else if (parameter == "frames") {
+            ss << stat.num_frames_modulated;
+        }
+    }
+    else {
+        ss << "Parameter '" << parameter <<
+            "' is not exported by controllable " << get_rc_name();
+        throw ParameterError(ss.str());
+    }
+    return ss.str();
+}
+
+} // namespace Output
diff --git a/src/output/SDR.h b/src/output/SDR.h
new file mode 100644
index 0000000..a55f7c0
--- /dev/null
+++ b/src/output/SDR.h
@@ -0,0 +1,95 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+
+DESCRIPTION:
+   Common interface for all SDR outputs
+*/
+
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#ifdef HAVE_CONFIG_H
+#   include <config.h>
+#endif
+
+#include <chrono>
+#include "ModPlugin.h"
+#include "EtiReader.h"
+#include "output/SDRDevice.h"
+#include "output/Feedback.h"
+
+namespace Output {
+
+using complexf = std::complex<float>;
+
+class SDR : public ModOutput, public ModMetadata, public RemoteControllable {
+    public:
+        SDR(SDRDeviceConfig& config, std::shared_ptr<SDRDevice> device);
+        SDR(const SDR& other) = delete;
+        SDR operator=(const SDR& other) = delete;
+        ~SDR();
+
+        virtual int process(Buffer *dataIn) override;
+        virtual meta_vec_t process_metadata(const meta_vec_t& metadataIn) override;
+
+        virtual const char* name() override;
+
+        /*********** REMOTE CONTROL ***************/
+
+        /* Base function to set parameters. */
+        virtual void set_parameter(const std::string& parameter,
+                const std::string& value) override;
+
+        /* Getting a parameter always returns a string. */
+        virtual const std::string get_parameter(
+                const std::string& parameter) const override;
+
+    private:
+        void process_thread_entry(void);
+        void handle_frame(struct FrameData &frame);
+        void sleep_through_frame(void);
+
+        SDRDeviceConfig& m_config;
+
+        std::atomic<bool> m_running = ATOMIC_VAR_INIT(false);
+        std::thread m_device_thread;
+        std::vector<uint8_t> m_frame;
+        ThreadsafeQueue<FrameData> m_queue;
+
+        std::shared_ptr<SDRDevice> m_device;
+        std::string m_name;
+
+        std::shared_ptr<DPDFeedbackServer> m_dpd_feedback_server;
+
+        bool     last_tx_time_initialised = false;
+        uint32_t last_tx_second = 0;
+        uint32_t last_tx_pps = 0;
+
+        bool     t_last_frame_initialised = false;
+        std::chrono::steady_clock::time_point t_last_frame;
+};
+
+}
+
diff --git a/src/output/SDRDevice.h b/src/output/SDRDevice.h
new file mode 100644
index 0000000..bd1a518
--- /dev/null
+++ b/src/output/SDRDevice.h
@@ -0,0 +1,137 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2017
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+
+DESCRIPTION:
+   Common interface for all SDR outputs
+*/
+
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#ifdef HAVE_CONFIG_H
+#   include <config.h>
+#endif
+
+#include <cstdint>
+#include <string>
+#include <vector>
+#include <complex>
+
+#include "TimestampDecoder.h"
+
+namespace Output {
+
+enum refclk_lock_loss_behaviour_t { CRASH, IGNORE };
+
+using complexf = std::complex<float>;
+
+/* This structure is used as initial configuration for all SDR devices.
+ * It must also contain all remote-controllable settings, otherwise
+ * they will get lost on a modulator restart. */
+struct SDRDeviceConfig {
+    std::string device;
+    std::string subDevice; // For UHD
+    std::string tx_antenna;
+    std::string rx_antenna;
+
+    long masterClockRate = 32768000;
+    unsigned sampleRate = 2048000;
+    double frequency = 0.0;
+    double lo_offset = 0.0;
+    double txgain = 0.0;
+    double rxgain = 0.0;
+    bool enableSync = false;
+
+    // When working with timestamps, mute the frames that
+    // do not have a timestamp
+    bool muteNoTimestamps = false;
+    unsigned dabMode = 0;
+    unsigned maxGPSHoldoverTime = 0;
+
+    /* allowed values for UHD : auto, int, sma, mimo */
+    std::string refclk_src;
+
+    /* allowed values for UHD : int, sma, mimo */
+    std::string pps_src;
+
+    /* allowed values for UHD : pos, neg */
+    std::string pps_polarity;
+
+    /* What to do when the reference clock PLL loses lock */
+    refclk_lock_loss_behaviour_t refclk_lock_loss_behaviour;
+
+    // muting can only be changed using the remote control
+    bool muting = false;
+
+    // TCP port on which to serve TX and RX samples for the
+    // digital pre distortion learning tool
+    uint16_t dpdFeedbackServerPort = 0;
+};
+
+// Each frame contains one OFDM frame, and its
+// associated timestamp
+struct FrameData {
+    // Buffer holding frame data
+    std::vector<uint8_t> buf;
+
+    // A full timestamp contains a TIST according to standard
+    // and time information within MNSC with tx_second.
+    struct frame_timestamp ts;
+};
+
+
+// All SDR Devices must implement the SDRDevice interface
+class SDRDevice {
+    public:
+        struct RunStatistics {
+            size_t num_underruns;
+            size_t num_late_packets;
+            size_t num_overruns;
+            size_t num_frames_modulated;
+        };
+
+        virtual void tune(double lo_offset, double frequency) = 0;
+        virtual double get_tx_freq(void) const = 0;
+        virtual void set_txgain(double txgain) = 0;
+        virtual double get_txgain(void) const = 0;
+        virtual void transmit_frame(const struct FrameData& frame) = 0;
+        virtual RunStatistics get_run_statistics(void) const = 0;
+        virtual double get_real_secs(void) const = 0;
+        virtual void set_rxgain(double rxgain) = 0;
+        virtual double get_rxgain(void) const = 0;
+        virtual size_t receive_frame(
+                complexf *buf,
+                size_t num_samples,
+                struct frame_timestamp& ts,
+                double timeout_secs) = 0;
+
+
+        // Return true if GPS and reference clock inputs are ok
+        virtual bool is_clk_source_ok(void) const = 0;
+
+        virtual const char* device_name(void) const = 0;
+};
+
+} // namespace Output
diff --git a/src/output/Soapy.cpp b/src/output/Soapy.cpp
new file mode 100644
index 0000000..8ee420e
--- /dev/null
+++ b/src/output/Soapy.cpp
@@ -0,0 +1,274 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+
+DESCRIPTION:
+   It is an output driver using the SoapySDR library that can output to
+   many devices.
+*/
+
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "output/Soapy.h"
+
+#ifdef HAVE_SOAPYSDR
+
+#include <SoapySDR/Errors.hpp>
+#include <chrono>
+#include <cstdio>
+
+#include "Log.h"
+#include "Utils.h"
+
+using namespace std;
+
+namespace Output {
+
+static constexpr size_t FRAMES_MAX_SIZE = 2;
+
+Soapy::Soapy(SDRDeviceConfig& config) :
+    SDRDevice(),
+    m_conf(config)
+{
+    etiLog.level(info) <<
+        "Soapy:Creating the device with: " <<
+        m_conf.device;
+
+    try {
+        m_device = SoapySDR::Device::make(m_conf.device);
+        stringstream ss;
+        ss << "SoapySDR driver=" << m_device->getDriverKey();
+        ss << " hardware=" << m_device->getHardwareKey();
+        for (const auto &it : m_device->getHardwareInfo()) {
+            ss << "  " << it.first << "=" << it.second;
+        }
+    }
+    catch (const std::exception &ex) {
+        etiLog.level(error) << "Error making SoapySDR device: " <<
+            ex.what();
+        throw std::runtime_error("Cannot create SoapySDR output");
+    }
+
+    m_device->setMasterClockRate(m_conf.masterClockRate);
+    etiLog.level(info) << "SoapySDR master clock rate set to " <<
+        std::fixed << std::setprecision(4) <<
+        m_device->getMasterClockRate()/1000.0 << " kHz";
+
+    m_device->setSampleRate(SOAPY_SDR_TX, 0, m_conf.sampleRate);
+    etiLog.level(info) << "SoapySDR:Actual TX rate: " <<
+        std::fixed << std::setprecision(4) <<
+        m_device->getSampleRate(SOAPY_SDR_TX, 0) / 1000.0 <<
+        " ksps.";
+
+    tune(m_conf.lo_offset, m_conf.frequency);
+    m_conf.frequency = m_device->getFrequency(SOAPY_SDR_TX, 0);
+    etiLog.level(info) << "SoapySDR:Actual frequency: " <<
+        std::fixed << std::setprecision(3) <<
+        m_conf.frequency / 1000.0 << " kHz.";
+
+    m_device->setGain(SOAPY_SDR_TX, 0, m_conf.txgain);
+    etiLog.level(info) << "SoapySDR:Actual tx gain: " <<
+        std::fixed << std::setprecision(2) <<
+        m_device->getGain(SOAPY_SDR_TX, 0);
+
+    if (not m_conf.tx_antenna.empty()) {
+        m_device->setAntenna(SOAPY_SDR_TX, 0, m_conf.tx_antenna);
+    }
+    etiLog.level(info) << "SoapySDR:Actual tx antenna: " <<
+        m_device->getAntenna(SOAPY_SDR_TX, 0);
+
+    const std::vector<size_t> channels({0});
+    m_tx_stream = m_device->setupStream(SOAPY_SDR_TX, "CF32", channels);
+    m_device->activateStream(m_tx_stream);
+
+    m_rx_stream = m_device->setupStream(SOAPY_SDR_RX, "CF32", channels);
+}
+
+Soapy::~Soapy()
+{
+    if (m_device != nullptr) {
+        if (m_tx_stream != nullptr) {
+            m_device->closeStream(m_tx_stream);
+        }
+        SoapySDR::Device::unmake(m_device);
+    }
+}
+
+void Soapy::tune(double lo_offset, double frequency)
+{
+    if (not m_device) throw runtime_error("Soapy device not set up");
+
+    SoapySDR::Kwargs offset_arg;
+    offset_arg["OFFSET"] = to_string(lo_offset);
+    m_device->setFrequency(SOAPY_SDR_TX, 0, m_conf.frequency, offset_arg);
+}
+
+double Soapy::get_tx_freq(void) const
+{
+    if (not m_device) throw runtime_error("Soapy device not set up");
+
+    // TODO lo offset
+    return m_device->getFrequency(SOAPY_SDR_TX, 0);
+}
+
+void Soapy::set_txgain(double txgain)
+{
+    m_conf.txgain = txgain;
+    if (not m_device) throw runtime_error("Soapy device not set up");
+    m_device->setGain(SOAPY_SDR_TX, 0, m_conf.txgain);
+}
+
+double Soapy::get_txgain(void) const
+{
+    if (not m_device) throw runtime_error("Soapy device not set up");
+    return m_device->getGain(SOAPY_SDR_TX, 0);
+}
+
+SDRDevice::RunStatistics Soapy::get_run_statistics(void) const
+{
+    RunStatistics rs;
+    rs.num_underruns = underflows;
+    rs.num_overruns = overflows;
+    rs.num_late_packets = late_packets;
+    rs.num_frames_modulated = num_frames_modulated;
+    return rs;
+}
+
+
+double Soapy::get_real_secs(void) const
+{
+    if (m_device) {
+        long long time_ns = m_device->getHardwareTime();
+        return time_ns / 1e9;
+    }
+    else {
+        return 0.0;
+    }
+}
+
+void Soapy::set_rxgain(double rxgain)
+{
+    m_device->setGain(SOAPY_SDR_RX, 0, m_conf.rxgain);
+    m_conf.rxgain = m_device->getGain(SOAPY_SDR_RX, 0);
+}
+
+double Soapy::get_rxgain(void) const
+{
+    return m_device->getGain(SOAPY_SDR_RX, 0);
+}
+
+size_t Soapy::receive_frame(
+        complexf *buf,
+        size_t num_samples,
+        struct frame_timestamp& ts,
+        double timeout_secs)
+{
+    int flags = 0;
+    long long timeNs = ts.get_ns();
+    const size_t numElems = num_samples;
+
+    void *buffs[1];
+    buffs[0] = buf;
+
+    m_device->activateStream(m_rx_stream, flags, timeNs, numElems);
+
+    auto ret = m_device->readStream(m_tx_stream, buffs, num_samples, flags, timeNs);
+
+    m_device->deactivateStream(m_rx_stream);
+
+    // TODO update effective receive ts
+
+    if (ret < 0) {
+        throw runtime_error("Soapy readStream error: " + to_string(ret));
+    }
+
+    return ret;
+}
+
+
+bool Soapy::is_clk_source_ok() const
+{
+    // TODO
+    return true;
+}
+
+const char* Soapy::device_name(void) const
+{
+    return "Soapy";
+}
+
+void Soapy::transmit_frame(const struct FrameData& frame)
+{
+    if (not m_device) throw runtime_error("Soapy device not set up");
+
+    // TODO timestamps
+
+    // The frame buffer contains bytes representing FC32 samples
+    const complexf *buf = reinterpret_cast<const complexf*>(frame.buf.data());
+    const size_t numSamples = frame.buf.size() / sizeof(complexf);
+    if ((frame.buf.size() % sizeof(complexf)) != 0) {
+        throw std::runtime_error("Soapy: invalid buffer size");
+    }
+
+    // Stream MTU is in samples, not bytes.
+    const size_t mtu = m_device->getStreamMTU(m_tx_stream);
+
+    size_t num_acc_samps = 0;
+    while (num_acc_samps < numSamples) {
+        const void *buffs[1];
+        buffs[0] = buf + num_acc_samps;
+
+        const size_t samps_to_send = std::min(numSamples - num_acc_samps, mtu);
+
+        int flags = 0;
+
+        auto ret = m_device->writeStream(m_tx_stream, buffs, samps_to_send, flags);
+
+        if (ret == SOAPY_SDR_TIMEOUT) {
+            continue;
+        }
+        else if (ret == SOAPY_SDR_OVERFLOW) {
+            overflows++;
+            continue;
+        }
+        else if (ret == SOAPY_SDR_UNDERFLOW) {
+            underflows++;
+            continue;
+        }
+
+        if (ret < 0) {
+            etiLog.level(error) << "Unexpected stream error " <<
+                SoapySDR::errToStr(ret);
+            throw std::runtime_error("Fault in Soapy");
+        }
+
+        num_acc_samps += ret;
+    }
+    num_frames_modulated++;
+}
+
+} // namespace Output
+
+#endif // HAVE_SOAPYSDR
+
+
diff --git a/src/output/Soapy.h b/src/output/Soapy.h
new file mode 100644
index 0000000..67b280d
--- /dev/null
+++ b/src/output/Soapy.h
@@ -0,0 +1,98 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+
+DESCRIPTION:
+   It is an output driver using the SoapySDR library that can output to
+   many devices.
+*/
+
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#ifdef HAVE_CONFIG_H
+#   include <config.h>
+#endif
+
+#ifdef HAVE_SOAPYSDR
+#include <SoapySDR/Version.hpp>
+#include <SoapySDR/Modules.hpp>
+#include <SoapySDR/Registry.hpp>
+#include <SoapySDR/Device.hpp>
+
+#include <string>
+#include <memory>
+
+#include "output/SDR.h"
+#include "ModPlugin.h"
+#include "EtiReader.h"
+#include "RemoteControl.h"
+#include "ThreadsafeQueue.h"
+
+namespace Output {
+
+class Soapy : public Output::SDRDevice
+{
+    public:
+        Soapy(SDRDeviceConfig& config);
+        Soapy(const Soapy& other) = delete;
+        Soapy& operator=(const Soapy& other) = delete;
+        ~Soapy();
+
+        virtual void tune(double lo_offset, double frequency) override;
+        virtual double get_tx_freq(void) const override;
+        virtual void set_txgain(double txgain) override;
+        virtual double get_txgain(void) const override;
+        virtual void transmit_frame(const struct FrameData& frame) override;
+        virtual RunStatistics get_run_statistics(void) const override;
+        virtual double get_real_secs(void) const override;
+
+        virtual void set_rxgain(double rxgain) override;
+        virtual double get_rxgain(void) const override;
+        virtual size_t receive_frame(
+                complexf *buf,
+                size_t num_samples,
+                struct frame_timestamp& ts,
+                double timeout_secs) override;
+
+        // Return true if GPS and reference clock inputs are ok
+        virtual bool is_clk_source_ok(void) const override;
+        virtual const char* device_name(void) const override;
+
+    private:
+        SDRDeviceConfig& m_conf;
+        SoapySDR::Device *m_device = nullptr;
+        SoapySDR::Stream *m_tx_stream = nullptr;
+        SoapySDR::Stream *m_rx_stream = nullptr;
+
+        size_t underflows = 0;
+        size_t overflows = 0;
+        size_t late_packets = 0;
+        size_t num_frames_modulated = 0;
+};
+
+} // namespace Output
+
+#endif //HAVE_SOAPYSDR
+
diff --git a/src/output/UHD.cpp b/src/output/UHD.cpp
new file mode 100644
index 0000000..2c571fd
--- /dev/null
+++ b/src/output/UHD.cpp
@@ -0,0 +1,500 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+ */
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "output/UHD.h"
+
+#ifdef HAVE_OUTPUT_UHD
+
+//#define MDEBUG(fmt, args...) fprintf(LOG, fmt , ## args)
+#define MDEBUG(fmt, args...)
+
+#include "PcDebug.h"
+#include "Log.h"
+#include "RemoteControl.h"
+#include "Utils.h"
+
+#include <boost/thread/future.hpp>
+
+#include <uhd/utils/msg.hpp>
+
+#include <cmath>
+#include <iostream>
+#include <assert.h>
+#include <stdexcept>
+#include <stdio.h>
+#include <time.h>
+#include <errno.h>
+#include <unistd.h>
+#include <pthread.h>
+
+using namespace std;
+
+namespace Output {
+
+// Maximum number of frames that can wait in frames
+static const size_t FRAMES_MAX_SIZE = 8;
+
+static std::string stringtrim(const std::string &s)
+{
+    auto wsfront = std::find_if_not(s.begin(), s.end(),
+            [](int c){ return std::isspace(c);} );
+    return std::string(wsfront,
+            std::find_if_not(s.rbegin(),
+                std::string::const_reverse_iterator(wsfront),
+                [](int c){ return std::isspace(c);} ).base());
+}
+
+static void uhd_msg_handler(uhd::msg::type_t type, const std::string &msg)
+{
+    if (type == uhd::msg::warning) {
+        etiLog.level(warn) << "UHD Warning: " << msg;
+    }
+    else if (type == uhd::msg::error) {
+        etiLog.level(error) << "UHD Error: " << msg;
+    }
+    else {
+        // do not print very short U messages and such
+        if (stringtrim(msg).size() != 1) {
+            etiLog.level(debug) << "UHD Message: " << msg;
+        }
+    }
+}
+
+
+
+UHD::UHD(SDRDeviceConfig& config) :
+    SDRDevice(),
+    m_conf(config),
+    m_running(false)
+{
+    std::stringstream device;
+    device << m_conf.device;
+
+    if (m_conf.masterClockRate != 0) {
+        if (device.str() != "") {
+            device << ",";
+        }
+        device << "master_clock_rate=" << m_conf.masterClockRate;
+    }
+
+    MDEBUG("OutputUHD::OutputUHD(device: %s) @ %p\n",
+            device.str().c_str(), this);
+
+    uhd::msg::register_handler(uhd_msg_handler);
+
+    uhd::set_thread_priority_safe();
+
+    etiLog.log(info, "OutputUHD:Creating the usrp device with: %s...",
+            device.str().c_str());
+
+    m_usrp = uhd::usrp::multi_usrp::make(device.str());
+
+    etiLog.log(info, "OutputUHD:Using device: %s...",
+            m_usrp->get_pp_string().c_str());
+
+    if (m_conf.masterClockRate != 0.0) {
+        double master_clk_rate = m_usrp->get_master_clock_rate();
+        etiLog.log(debug, "OutputUHD:Checking master clock rate: %f...",
+                master_clk_rate);
+
+        if (fabs(master_clk_rate - m_conf.masterClockRate) >
+                (m_conf.masterClockRate * 1e-6)) {
+            throw std::runtime_error("Cannot set USRP master_clock_rate. Aborted.");
+        }
+    }
+
+    MDEBUG("OutputUHD:Setting REFCLK and PPS input...\n");
+
+    if (m_conf.refclk_src == "gpsdo-ettus") {
+        m_usrp->set_clock_source("gpsdo");
+    }
+    else {
+        m_usrp->set_clock_source(m_conf.refclk_src);
+    }
+    m_usrp->set_time_source(m_conf.pps_src);
+
+    m_device_time = std::make_shared<USRPTime>(m_usrp, m_conf);
+
+    if (m_conf.subDevice != "") {
+        m_usrp->set_tx_subdev_spec(uhd::usrp::subdev_spec_t(m_conf.subDevice),
+                uhd::usrp::multi_usrp::ALL_MBOARDS);
+    }
+
+    etiLog.level(debug) << "UHD clock source is " << m_usrp->get_clock_source(0);
+
+    etiLog.level(debug) << "UHD time source is " << m_usrp->get_time_source(0);
+
+    m_usrp->set_tx_rate(m_conf.sampleRate);
+    etiLog.log(debug, "OutputUHD:Set rate to %d. Actual TX Rate: %f sps...",
+            m_conf.sampleRate, m_usrp->get_tx_rate());
+
+    if (fabs(m_usrp->get_tx_rate() / m_conf.sampleRate) >
+             m_conf.sampleRate * 1e-6) {
+        throw std::runtime_error("Cannot set USRP sample rate. Aborted.");
+    }
+
+    tune(m_conf.lo_offset, m_conf.frequency);
+
+    m_conf.frequency = m_usrp->get_tx_freq();
+    etiLog.level(debug) << std::fixed << std::setprecision(3) <<
+        "OutputUHD:Actual TX frequency: " << m_conf.frequency;
+
+    etiLog.level(debug) << std::fixed << std::setprecision(3) <<
+        "OutputUHD:Actual RX frequency: " << m_usrp->get_tx_freq();
+
+    m_usrp->set_tx_gain(m_conf.txgain);
+    m_conf.txgain = m_usrp->get_tx_gain();
+    etiLog.log(debug, "OutputUHD:Actual TX Gain: %f", m_conf.txgain);
+
+    etiLog.log(debug, "OutputUHD:Mute on missing timestamps: %s",
+            m_conf.muteNoTimestamps ? "enabled" : "disabled");
+
+    m_usrp->set_rx_rate(m_conf.sampleRate);
+    etiLog.log(debug, "OutputUHD:Actual RX Rate: %f sps.", m_usrp->get_rx_rate());
+
+    if (not m_conf.rx_antenna.empty()) {
+        m_usrp->set_rx_antenna(m_conf.rx_antenna);
+    }
+    etiLog.log(debug, "OutputUHD:Actual RX Antenna: %s",
+            m_usrp->get_rx_antenna().c_str());
+
+    if (not m_conf.tx_antenna.empty()) {
+        m_usrp->set_tx_antenna(m_conf.tx_antenna);
+    }
+    etiLog.log(debug, "OutputUHD:Actual TX Antenna: %s",
+            m_usrp->get_tx_antenna().c_str());
+
+    m_usrp->set_rx_gain(m_conf.rxgain);
+    etiLog.log(debug, "OutputUHD:Actual RX Gain: %f", m_usrp->get_rx_gain());
+
+    const uhd::stream_args_t stream_args("fc32"); //complex floats
+    m_rx_stream = m_usrp->get_rx_stream(stream_args);
+    m_tx_stream = m_usrp->get_tx_stream(stream_args);
+
+    m_running.store(true);
+    m_async_rx_thread = boost::thread(&UHD::print_async_thread, this);
+
+    MDEBUG("OutputUHD:UHD ready.\n");
+}
+
+UHD::~UHD()
+{
+    stop_threads();
+}
+
+void UHD::tune(double lo_offset, double frequency)
+{
+    if (lo_offset != 0.0) {
+        etiLog.level(info) << std::fixed << std::setprecision(3) <<
+            "OutputUHD:Setting freq to " << frequency <<
+            "  with LO offset " << lo_offset << "...";
+
+        const auto tr = uhd::tune_request_t(frequency, lo_offset);
+        uhd::tune_result_t result = m_usrp->set_tx_freq(tr);
+
+        etiLog.level(debug) << "OutputUHD: TX freq" <<
+            std::fixed << std::setprecision(0) <<
+            " Target RF: " << result.target_rf_freq <<
+            " Actual RF: " << result.actual_rf_freq <<
+            " Target DSP: " << result.target_dsp_freq <<
+            " Actual DSP: " << result.actual_dsp_freq;
+
+        uhd::tune_result_t result_rx = m_usrp->set_rx_freq(tr);
+
+        etiLog.level(debug) << "OutputUHD: RX freq" <<
+            std::fixed << std::setprecision(0) <<
+            " Target RF: " << result_rx.target_rf_freq <<
+            " Actual RF: " << result_rx.actual_rf_freq <<
+            " Target DSP: " << result_rx.target_dsp_freq <<
+            " Actual DSP: " << result_rx.actual_dsp_freq;
+    }
+    else {
+        //set the centre frequency
+        etiLog.level(info) << std::fixed << std::setprecision(3) <<
+            "OutputUHD:Setting freq to " << frequency << "...";
+        m_usrp->set_tx_freq(frequency);
+
+        m_usrp->set_rx_freq(frequency);
+    }
+}
+
+double UHD::get_tx_freq(void) const
+{
+    return m_usrp->get_tx_freq();
+}
+
+void UHD::set_txgain(double txgain)
+{
+    m_usrp->set_tx_gain(txgain);
+    m_conf.txgain = m_usrp->get_tx_gain();
+}
+
+double UHD::get_txgain(void) const
+{
+    return m_usrp->get_tx_gain();
+}
+
+void UHD::transmit_frame(const struct FrameData& frame)
+{
+    const double tx_timeout = 20.0;
+    const size_t sizeIn = frame.buf.size() / sizeof(complexf);
+    const complexf* in_data = reinterpret_cast<const complexf*>(&frame.buf[0]);
+
+    uhd::tx_metadata_t md_tx;
+
+    bool tx_allowed = true;
+
+    // muting and mutenotimestamp is handled by SDR
+    if (m_conf.enableSync and frame.ts.timestamp_valid) {
+        uhd::time_spec_t timespec(
+                frame.ts.timestamp_sec, frame.ts.pps_offset());
+        md_tx.time_spec = timespec;
+        md_tx.has_time_spec = true;
+    }
+    else {
+        md_tx.has_time_spec = false;
+    }
+
+    size_t usrp_max_num_samps = m_tx_stream->get_max_num_samps();
+    size_t num_acc_samps = 0; //number of accumulated samples
+    while (tx_allowed and m_running.load() and (num_acc_samps < sizeIn)) {
+        size_t samps_to_send = std::min(sizeIn - num_acc_samps, usrp_max_num_samps);
+
+        const bool eob_because_muting = m_conf.muting;
+
+        // ensure the the last packet has EOB set if the timestamps has been
+        // refreshed and need to be reconsidered. If muting was set, set the
+        // EOB and quit the loop afterwards, to avoid an underrun.
+        md_tx.end_of_burst = eob_because_muting or (
+                frame.ts.timestamp_valid and
+                frame.ts.timestamp_refresh and
+                samps_to_send <= usrp_max_num_samps );
+
+        //send a single packet
+        size_t num_tx_samps = m_tx_stream->send(
+                &in_data[num_acc_samps],
+                samps_to_send, md_tx, tx_timeout);
+        etiLog.log(trace, "UHD,sent %zu of %zu", num_tx_samps, samps_to_send);
+
+        num_acc_samps += num_tx_samps;
+
+        md_tx.time_spec = md_tx.time_spec +
+            uhd::time_spec_t(0, num_tx_samps/m_conf.sampleRate);
+
+        if (num_tx_samps == 0) {
+            etiLog.log(warn,
+                    "OutputUHD unable to write to device, skipping frame!");
+            break;
+        }
+
+        if (eob_because_muting) {
+            break;
+        }
+    }
+
+    num_frames_modulated++;
+}
+
+
+SDRDevice::RunStatistics UHD::get_run_statistics(void) const
+{
+    RunStatistics rs;
+    rs.num_underruns = num_underflows;
+    rs.num_overruns = num_overflows;
+    rs.num_late_packets = num_late_packets;
+    rs.num_frames_modulated = num_frames_modulated;
+    return rs;
+}
+
+double UHD::get_real_secs(void) const
+{
+    return m_usrp->get_time_now().get_real_secs();
+}
+
+void UHD::set_rxgain(double rxgain)
+{
+    m_usrp->set_rx_gain(m_conf.rxgain);
+    m_conf.rxgain = m_usrp->get_rx_gain();
+}
+
+double UHD::get_rxgain() const
+{
+    return m_usrp->get_rx_gain();
+}
+
+size_t UHD::receive_frame(
+        complexf *buf,
+        size_t num_samples,
+        struct frame_timestamp& ts,
+        double timeout_secs)
+{
+    uhd::stream_cmd_t cmd(
+            uhd::stream_cmd_t::stream_mode_t::STREAM_MODE_NUM_SAMPS_AND_DONE);
+    cmd.num_samps = num_samples;
+    cmd.stream_now = false;
+    cmd.time_spec = uhd::time_spec_t(ts.timestamp_sec, ts.pps_offset());
+
+    m_rx_stream->issue_stream_cmd(cmd);
+
+    uhd::rx_metadata_t md_rx;
+
+    constexpr double timeout = 60;
+    size_t samples_read = m_rx_stream->recv(buf, num_samples, md_rx, timeout);
+
+    // Update the ts with the effective receive TS
+    ts.timestamp_sec = md_rx.time_spec.get_full_secs();
+    ts.timestamp_pps = md_rx.time_spec.get_frac_secs() * 16384000.0;
+    return samples_read;
+}
+
+// Return true if GPS and reference clock inputs are ok
+bool UHD::is_clk_source_ok(void) const
+{
+    bool ok = true;
+
+    if (refclk_loss_needs_check()) {
+        try {
+            if (not m_usrp->get_mboard_sensor("ref_locked", 0).to_bool()) {
+                ok = false;
+
+                etiLog.level(alert) <<
+                    "OutputUHD: External reference clock lock lost !";
+
+                if (m_conf.refclk_lock_loss_behaviour == CRASH) {
+                    throw std::runtime_error(
+                            "OutputUHD: External reference clock lock lost.");
+                }
+            }
+        }
+        catch (uhd::lookup_error &e) {
+            suppress_refclk_loss_check = true;
+            etiLog.log(warn, "OutputUHD: This USRP does not have mboard "
+                    "sensor for ext clock loss. Check disabled.");
+        }
+    }
+
+    if (m_device_time) {
+        ok |= m_device_time->verify_time();
+    }
+
+    return ok;
+}
+
+const char* UHD::device_name(void) const
+{
+    return "UHD";
+}
+
+
+bool UHD::refclk_loss_needs_check() const
+{
+    if (suppress_refclk_loss_check) {
+        return false;
+    }
+    return m_conf.refclk_src != "internal";
+}
+
+void UHD::stop_threads()
+{
+    m_running.store(false);
+    if (m_async_rx_thread.joinable()) {
+        m_async_rx_thread.join();
+    }
+}
+
+
+
+void UHD::print_async_thread()
+{
+    while (m_running.load()) {
+        uhd::async_metadata_t async_md;
+        if (m_usrp->get_device()->recv_async_msg(async_md, 1)) {
+            const char* uhd_async_message = "";
+            bool failure = false;
+            switch (async_md.event_code) {
+                case uhd::async_metadata_t::EVENT_CODE_BURST_ACK:
+                    break;
+                case uhd::async_metadata_t::EVENT_CODE_UNDERFLOW:
+                    uhd_async_message = "Underflow";
+                    num_underflows++;
+                    break;
+                case uhd::async_metadata_t::EVENT_CODE_SEQ_ERROR:
+                    uhd_async_message = "Packet loss between host and device.";
+                    failure = true;
+                    break;
+                case uhd::async_metadata_t::EVENT_CODE_TIME_ERROR:
+                    uhd_async_message = "Packet had time that was late.";
+                    num_late_packets++;
+                    break;
+                case uhd::async_metadata_t::EVENT_CODE_UNDERFLOW_IN_PACKET:
+                    uhd_async_message = "Underflow occurred inside a packet.";
+                    failure = true;
+                    break;
+                case uhd::async_metadata_t::EVENT_CODE_SEQ_ERROR_IN_BURST:
+                    uhd_async_message = "Packet loss within a burst.";
+                    failure = true;
+                    break;
+                default:
+                    uhd_async_message = "unknown event code";
+                    failure = true;
+                    break;
+            }
+
+            if (failure) {
+                etiLog.level(alert) <<
+                    "Received Async UHD Message '" <<
+                    uhd_async_message << "' at time " <<
+                    async_md.time_spec.get_real_secs();
+            }
+        }
+
+        auto time_now = std::chrono::steady_clock::now();
+        if (last_print_time + std::chrono::seconds(1) < time_now) {
+            const double usrp_time =
+                m_usrp->get_time_now().get_real_secs();
+
+            if ( (num_underflows > num_underflows_previous) or
+                 (num_late_packets > num_late_packets_previous)) {
+                etiLog.log(info,
+                        "OutputUHD status (usrp time: %f): "
+                        "%d underruns and %d late packets since last status.\n",
+                        usrp_time,
+                        num_underflows - num_underflows_previous,
+                        num_late_packets - num_late_packets_previous);
+            }
+
+            num_underflows_previous = num_underflows;
+            num_late_packets_previous = num_late_packets;
+
+            last_print_time = time_now;
+        }
+    }
+}
+
+} // namespace Output
+
+#endif // HAVE_OUTPUT_UHD
+
diff --git a/src/output/UHD.h b/src/output/UHD.h
new file mode 100644
index 0000000..b34455c
--- /dev/null
+++ b/src/output/UHD.h
@@ -0,0 +1,127 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+
+DESCRIPTION:
+   It is an output driver for the USRP family of devices, and uses the UHD
+   library.
+*/
+
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#ifdef HAVE_CONFIG_H
+#   include <config.h>
+#endif
+
+#ifdef HAVE_OUTPUT_UHD
+
+#include <uhd/utils/thread_priority.hpp>
+#include <uhd/utils/safe_main.hpp>
+#include <uhd/usrp/multi_usrp.hpp>
+#include <chrono>
+#include <memory>
+#include <string>
+#include <atomic>
+
+#include "Log.h"
+#include "output/SDR.h"
+#include "output/USRPTime.h"
+#include "TimestampDecoder.h"
+#include "RemoteControl.h"
+#include "ThreadsafeQueue.h"
+
+#include <stdio.h>
+#include <sys/types.h>
+
+// If the timestamp is further in the future than
+// 100 seconds, abort
+#define TIMESTAMP_ABORT_FUTURE 100
+
+// Add a delay to increase buffers when
+// frames are too far in the future
+#define TIMESTAMP_MARGIN_FUTURE 0.5
+
+namespace Output {
+
+class UHD : public Output::SDRDevice
+{
+    public:
+        UHD(SDRDeviceConfig& config);
+        UHD(const UHD& other) = delete;
+        UHD& operator=(const UHD& other) = delete;
+        ~UHD();
+
+        virtual void tune(double lo_offset, double frequency) override;
+        virtual double get_tx_freq(void) const override;
+        virtual void set_txgain(double txgain) override;
+        virtual double get_txgain(void) const override;
+        virtual void transmit_frame(const struct FrameData& frame) override;
+        virtual RunStatistics get_run_statistics(void) const override;
+        virtual double get_real_secs(void) const override;
+
+        virtual void set_rxgain(double rxgain) override;
+        virtual double get_rxgain(void) const override;
+        virtual size_t receive_frame(
+                complexf *buf,
+                size_t num_samples,
+                struct frame_timestamp& ts,
+                double timeout_secs) override;
+
+        // Return true if GPS and reference clock inputs are ok
+        virtual bool is_clk_source_ok(void) const override;
+        virtual const char* device_name(void) const override;
+
+    private:
+        SDRDeviceConfig& m_conf;
+        uhd::usrp::multi_usrp::sptr m_usrp;
+        uhd::tx_streamer::sptr m_tx_stream;
+        uhd::rx_streamer::sptr m_rx_stream;
+        std::shared_ptr<USRPTime> m_device_time;
+
+        size_t num_underflows = 0;
+        size_t num_overflows = 0;
+        size_t num_late_packets = 0;
+        size_t num_frames_modulated = 0;
+        size_t num_underflows_previous = 0;
+        size_t num_late_packets_previous = 0;
+
+        // Used to print statistics once a second
+        std::chrono::steady_clock::time_point last_print_time;
+
+        // Returns true if we want to verify loss of refclk
+        bool refclk_loss_needs_check(void) const;
+        mutable bool suppress_refclk_loss_check = false;
+
+        // Poll asynchronous metadata from UHD
+        std::atomic<bool> m_running;
+        boost::thread m_async_rx_thread;
+        void stop_threads(void);
+        void print_async_thread(void);
+};
+
+} // namespace Output
+
+#endif // HAVE_OUTPUT_UHD
+
diff --git a/src/output/USRPTime.cpp b/src/output/USRPTime.cpp
new file mode 100644
index 0000000..935d56b
--- /dev/null
+++ b/src/output/USRPTime.cpp
@@ -0,0 +1,283 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2018
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+
+DESCRIPTION:
+   The part of the UHD output that takes care of the GPSDO.
+*/
+
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "output/USRPTime.h"
+
+#ifdef HAVE_OUTPUT_UHD
+
+//#define MDEBUG(fmt, args...) fprintf(LOG, fmt , ## args)
+#define MDEBUG(fmt, args...)
+
+namespace Output {
+
+using namespace std;
+
+
+// Check function for GPS TIMELOCK sensor from the ODR LEA-M8F board GPSDO
+static bool check_gps_timelock(uhd::usrp::multi_usrp::sptr& usrp)
+{
+    try {
+        const string sensor_value =
+            usrp->get_mboard_sensor("gps_timelock", 0).to_pp_string();
+
+        if (sensor_value.find("TIME LOCKED") == string::npos) {
+            etiLog.level(warn) << "OutputUHD: gps_timelock " << sensor_value;
+            return false;
+        }
+
+        return true;
+    }
+    catch (const uhd::lookup_error &e) {
+        etiLog.level(warn) << "OutputUHD: no gps_timelock sensor";
+        return false;
+    }
+}
+
+// Check function for GPS LOCKED sensor from the Ettus GPSDO
+static bool check_gps_locked(uhd::usrp::multi_usrp::sptr& usrp)
+{
+    try {
+        const uhd::sensor_value_t sensor_value(
+                usrp->get_mboard_sensor("gps_locked", 0));
+        if (not sensor_value.to_bool()) {
+            etiLog.level(warn) << "OutputUHD: gps_locked " <<
+                sensor_value.to_pp_string();
+            return false;
+        }
+
+        return true;
+    }
+    catch (const uhd::lookup_error &e) {
+        etiLog.level(warn) << "OutputUHD: no gps_locked sensor";
+        return false;
+    }
+}
+
+
+USRPTime::USRPTime(
+        uhd::usrp::multi_usrp::sptr usrp,
+        SDRDeviceConfig& conf) :
+    m_usrp(usrp),
+    m_conf(conf),
+    time_last_check(timepoint_t::clock::now())
+{
+    if (m_conf.pps_src == "none") {
+        if (m_conf.enableSync) {
+            etiLog.level(warn) <<
+                "OutputUHD: WARNING:"
+                " you are using synchronous transmission without PPS input!";
+        }
+
+        set_usrp_time_from_localtime();
+    }
+    else if (m_conf.pps_src == "pps" or m_conf.pps_src == "gpsdo") {
+        set_usrp_time_from_pps();
+    }
+    else {
+        throw std::runtime_error("USRPTime not implemented yet: " +
+                m_conf.pps_src);
+    }
+}
+
+bool USRPTime::verify_time()
+{
+    if (not gpsfix_needs_check()) {
+        return true;
+    }
+
+    /* During bootup, we say the gpsdo is not ok, and we poll the GPSDO until
+     * we reach lock. Then we sync time. If we do not reach lock in time, we
+     * crash.
+     *
+     * Once we are synced and we have lock, everything ok. If we lose lock for
+     * a number of seconds, we switch to the lost_fix state.
+     *
+     * In the lost fix state, we return false to get the TX muted, and we monitor.
+     * If the fix comes back, we unmute. If we reach the timeout, we crash.
+     */
+
+    check_gps();
+
+    const auto duration_without_fix =
+        gps_fix_check_interval * num_checks_without_gps_fix;
+
+    switch (gps_state) {
+        case gps_state_e::bootup:
+            if (duration_without_fix > initial_gps_fix_wait) {
+                throw runtime_error("GPS did not fix in " +
+                        to_string(initial_gps_fix_wait) + " seconds");
+            }
+
+            if (num_checks_without_gps_fix == 0) {
+                if (m_conf.pps_src != "none") {
+                    set_usrp_time_from_pps();
+                }
+                gps_state = gps_state_e::monitor_fix;
+                return true;
+            }
+
+            return false;
+
+        case gps_state_e::monitor_fix:
+            if (duration_without_fix > m_conf.maxGPSHoldoverTime) {
+                throw runtime_error("Lost GPS Fix for " +
+                        to_string(duration_without_fix) + " seconds");
+            }
+
+            return true;
+    }
+
+    throw logic_error("End of USRPTime::verify_time() reached");
+}
+
+void USRPTime::check_gps()
+{
+    timepoint_t time_now = timepoint_t::clock::now();
+
+    // Divide interval by two because we alternate between
+    // launch and check
+    const auto checkinterval = chrono::seconds(lrint(gps_fix_check_interval/2.0));
+
+    if (gpsfix_needs_check() and time_last_check + checkinterval < time_now) {
+        time_last_check = time_now;
+
+        // Alternate between launching thread and checking the
+        // result.
+        if (gps_fix_task.joinable()) {
+            if (gps_fix_future.has_value()) {
+
+                gps_fix_future.wait();
+
+                gps_fix_task.join();
+
+                if (not gps_fix_future.get()) {
+                    if (num_checks_without_gps_fix == 0) {
+                        etiLog.level(alert) << "OutputUHD: GPS Time Lock lost";
+                    }
+                    num_checks_without_gps_fix++;
+                }
+                else {
+                    if (num_checks_without_gps_fix) {
+                        etiLog.level(info) << "OutputUHD: GPS Time Lock recovered";
+                    }
+                    num_checks_without_gps_fix = 0;
+                }
+            }
+        }
+        else {
+            // Checking the sensor here takes too much
+            // time, it has to be done in a separate thread.
+            if (gpsdo_is_ettus()) {
+                gps_fix_pt = boost::packaged_task<bool>(
+                        boost::bind(check_gps_locked, m_usrp) );
+            }
+            else {
+                gps_fix_pt = boost::packaged_task<bool>(
+                        boost::bind(check_gps_timelock, m_usrp) );
+            }
+            gps_fix_future = gps_fix_pt.get_future();
+
+            gps_fix_task = boost::thread(boost::move(gps_fix_pt));
+        }
+    }
+}
+
+bool USRPTime::gpsfix_needs_check() const
+{
+    if (m_conf.refclk_src == "internal") {
+        return false;
+    }
+    else if (m_conf.refclk_src == "gpsdo") {
+        return (m_conf.maxGPSHoldoverTime != 0);
+    }
+    else if (m_conf.refclk_src == "gpsdo-ettus") {
+        return (m_conf.maxGPSHoldoverTime != 0);
+    }
+    else {
+        return false;
+    }
+}
+
+bool USRPTime::gpsdo_is_ettus() const
+{
+    return (m_conf.refclk_src == "gpsdo-ettus");
+}
+
+/* Return a uhd:time_spec representing current system time
+ * with 1ms granularity.  */
+static uhd::time_spec_t uhd_timespec_now(void)
+{
+    using namespace std::chrono;
+    auto n = system_clock::now();
+    const long long ticks = duration_cast<milliseconds>(n.time_since_epoch()).count();
+    return uhd::time_spec_t::from_ticks(ticks, 1000);
+}
+
+void USRPTime::set_usrp_time_from_localtime()
+{
+    const auto t = uhd_timespec_now();
+    m_usrp->set_time_now(t);
+
+    etiLog.level(info) << "OutputUHD: Setting USRP time to " <<
+        std::fixed << t.get_real_secs();
+}
+
+void USRPTime::set_usrp_time_from_pps()
+{
+    using namespace std::chrono;
+
+    /* handling time for synchronisation: wait until the next full
+     * second, and set the USRP time at next PPS */
+    auto now = uhd_timespec_now();
+    const time_t secs_since_epoch = now.get_full_secs();
+
+    while (secs_since_epoch + 1 > now.get_full_secs()) {
+        this_thread::sleep_for(milliseconds(1));
+        now = uhd_timespec_now();
+    }
+    /* We are now shortly after the second change.
+     * Wait 200ms to ensure the PPS comes later. */
+    this_thread::sleep_for(milliseconds(200));
+
+    const auto time_set = uhd::time_spec_t(secs_since_epoch + 2);
+    etiLog.level(info) << "OutputUHD: Setting USRP time next pps to " <<
+        std::fixed << time_set.get_real_secs();
+    m_usrp->set_time_next_pps(time_set);
+
+    // The UHD doc says we need to give the USRP one second to update
+    // all the internal registers.
+    this_thread::sleep_for(seconds(1));
+    etiLog.level(info) << "OutputUHD: USRP time " <<
+        std::fixed << m_usrp->get_time_now().get_real_secs();
+}
+
+} // namespace Output
+
+#endif // HAVE_OUTPUT_UHD
diff --git a/src/output/USRPTime.h b/src/output/USRPTime.h
new file mode 100644
index 0000000..7527f21
--- /dev/null
+++ b/src/output/USRPTime.h
@@ -0,0 +1,116 @@
+/*
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Her Majesty the
+   Queen in Right of Canada (Communications Research Center Canada)
+
+   Copyright (C) 2017
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+    http://opendigitalradio.org
+
+DESCRIPTION:
+   The part of the UHD output that takes care of the GPSDO and setting device
+   time.
+*/
+
+/*
+   This file is part of ODR-DabMod.
+
+   ODR-DabMod is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the
+   License, or (at your option) any later version.
+
+   ODR-DabMod is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#ifdef HAVE_CONFIG_H
+#   include <config.h>
+#endif
+
+#ifdef HAVE_OUTPUT_UHD
+
+#include <uhd/usrp/multi_usrp.hpp>
+#include <chrono>
+#include <memory>
+#include <string>
+#include <atomic>
+
+#include "Log.h"
+#include "output/SDR.h"
+#include "TimestampDecoder.h"
+#include "RemoteControl.h"
+#include "ThreadsafeQueue.h"
+
+#include <stdio.h>
+#include <sys/types.h>
+
+namespace Output {
+
+class USRPTime {
+    public:
+        USRPTime( uhd::usrp::multi_usrp::sptr usrp,
+                SDRDeviceConfig& conf);
+
+        // Verifies the GPSDO state, that the device time is ok.
+        // Returns true if all ok.
+        // Should be called more often than the gps_fix_check_interval
+        bool verify_time(void);
+
+        // Wait time in seconds to get fix
+        static const int initial_gps_fix_wait = 180;
+
+        // Interval for checking the GPS at runtime
+        static constexpr double gps_fix_check_interval = 10.0; // seconds
+
+    private:
+        enum class gps_state_e {
+            /* At startup, the LEA-M8F GPSDO gets issued a hotstart request to
+             * make sure we will not sync time on a PPS edge that is generated
+             * while the GPSDO is in holdover. In the bootup state, we wait for
+             * the first PPS after hotstart, and then sync time.
+             */
+            bootup,
+
+            /* Once the system is up, we check lock every now and then. If the
+             * fix is lost for too long, we crash.
+             */
+            monitor_fix,
+        };
+
+        void check_gps();
+
+        uhd::usrp::multi_usrp::sptr m_usrp;
+        SDRDeviceConfig& m_conf;
+
+        gps_state_e gps_state = gps_state_e::bootup;
+        int num_checks_without_gps_fix = 1;
+
+        using timepoint_t = std::chrono::time_point<std::chrono::steady_clock>;
+        timepoint_t time_last_check;
+
+        boost::packaged_task<bool> gps_fix_pt;
+        boost::unique_future<bool> gps_fix_future;
+        boost::thread gps_fix_task;
+
+        // Returns true if we want to check for the gps_timelock sensor
+        bool gpsfix_needs_check(void) const;
+
+        // Return true if the gpsdo is from ettus, false if it is the ODR
+        // LEA-M8F board is used
+        bool gpsdo_is_ettus(void) const;
+
+        void set_usrp_time_from_localtime(void);
+        void set_usrp_time_from_pps(void);
+};
+
+} // namespace Output
+
+#endif // HAVE_OUTPUT_UHD