Make gainmode VAR the default and update config to accept gainmode identifiers

3 files changed, 23 insertions, 14 deletions

diff --git a/doc/example.ini b/doc/example.ini
index 259ee4a..6a4b0f4 100644
--- a/doc/example.ini
+++ b/doc/example.ini
@@ -64,25 +64,23 @@ loop=0
 ;source=localhost:9200
 
 [modulator]
-; Gain mode: 0=FIX, 1=MAX, 2=VAR
-;
-;   Mode 0 (FIX) uses a fixed factor and is really not recommended. It is more
+;   Mode 'fix' uses a fixed factor and is really not recommended. It is more
 ; useful on an academic perspective for people trying to understand the DAB
 ; modulation.
 ;
-;   Mode 1 (MAX) is the normalization of every OFDM symbol. No overshoot, no
+;   Mode 'max' is the normalization of every OFDM symbol. No overshoot, no
 ; truncating, but varying output power (around 3dB) which might not be the best
 ; for some power amplifier. The output samples are limited to a magnitude
 ; of 32768.
 ;
-;   Mode 2 (VAR) uses the method specified in ETSI 300 798. This method
+;   Mode 'var' uses the method specified in ETSI 300 798. This method
 ; normalizes to 4 times the standard deviation for an approximation of the RMS
 ; power. So around 6/100000 samples will be truncated and will introduce some
 ; really minor distortion. But this mode also maximizes the output power. This
 ; is the gain mode recommended for real world operation as it is based on a DAB
 ; standard; the only difference is that ODR-DabMod uses a better resolution
 ; with 16 bits instead of 8 bits.
-gainmode=2
+gainmode=var
 
 ; Transmission mode
 ; If not defined, take the mode from ETI
diff --git a/src/DabMod.cpp b/src/DabMod.cpp
index 1cbbcbc..194c441 100644
--- a/src/DabMod.cpp
+++ b/src/DabMod.cpp
@@ -3,7 +3,7 @@
    Her Majesty the Queen in Right of Canada (Communications Research
    Center Canada)
 
-   Copyright (C) 2014, 2015
+   Copyright (C) 2016
    Matthias P. Braendli, matthias.braendli@mpb.li
 
     http://opendigitalradio.org
@@ -110,6 +110,19 @@ enum class run_modulator_state_t {
 
 run_modulator_state_t run_modulator(modulator_data& m);
 
+static GainMode parse_gainmode(const std::string &gainMode_setting)
+{
+    string gainMode_minuscule(gainMode_setting);
+    std::transform(gainMode_minuscule.begin(), gainMode_minuscule.end(), gainMode_minuscule.begin(), ::tolower);
+
+    if (gainMode_minuscule == "0" or gainMode_minuscule == "fix") { return GainMode::GAIN_FIX; }
+    else if (gainMode_minuscule == "1" or gainMode_minuscule == "max") { return GainMode::GAIN_MAX; }
+    else if (gainMode_minuscule == "2" or gainMode_minuscule == "var") { return GainMode::GAIN_VAR; }
+
+    cerr << "Modulator gainmode setting '" << gainMode_setting << "' not recognised." << endl;
+    throw std::runtime_error("Configuration error");
+}
+
 int launch_modulator(int argc, char* argv[])
 {
     int ret = 0;
@@ -227,7 +240,7 @@ int launch_modulator(int argc, char* argv[])
 #endif
             break;
         case 'g':
-            gainMode = (GainMode)strtol(optarg, NULL, 0);
+            gainMode = parse_gainmode(optarg);
             break;
         case 'G':
 #if defined(HAVE_OUTPUT_UHD)
@@ -400,7 +413,9 @@ int launch_modulator(int argc, char* argv[])
 
 
         // modulator parameters:
-        gainMode = (GainMode)pt.get("modulator.gainmode", 0);
+        const string gainMode_setting = pt.get("modulator.gainmode", "var");
+        gainMode = parse_gainmode(gainMode_setting);
+
         dabMode = pt.get("modulator.mode", dabMode);
         clockRate = pt.get("modulator.dac_clk_rate", (size_t)0);
         digitalgain = pt.get("modulator.digital_gain", digitalgain);
diff --git a/src/Utils.cpp b/src/Utils.cpp
index dd119a7..54a4161 100644
--- a/src/Utils.cpp
+++ b/src/Utils.cpp
@@ -75,11 +75,7 @@ void printUsage(char* progName)
     fprintf(out, "-T taps_file:  Enable filtering before the output, using the specified file containing the filter taps.\n");
     fprintf(out, "-a gain:       Apply digital amplitude gain.\n");
     fprintf(out, "-c rate:       Set the DAC clock rate and enable Cic Equalisation.\n");
-    fprintf(out, "-g:            Set computation gain mode: "
-            "%u FIX, %u MAX, %u VAR\n",
-            (unsigned int)GainMode::GAIN_FIX,
-            (unsigned int)GainMode::GAIN_MAX,
-            (unsigned int)GainMode::GAIN_VAR);
+    fprintf(out, "-g gainmode:   Set computation gain mode: fix, max or var\n");
     fprintf(out, "-h:            Print this help.\n");
     fprintf(out, "-l:            Loop file when reach end of file.\n");
     fprintf(out, "-m mode:       Set DAB mode: (0: auto, 1-4: force).\n");