/*
Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
2011, 2012 Her Majesty the Queen in Right of Canada (Communications
Research Center Canada)
Copyright (C) 2020
Matthias P. Braendli, matthias.braendli@mpb.li
*/
/*
This file is part of ODR-DabMux.
ODR-DabMux 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-DabMux 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-DabMux. If not, see .
*/
#include
#include
#include "DabMultiplexer.h"
#include "ConfigParser.h"
#include "fig/FIG.h"
using namespace std;
static vector split_pipe_separated_string(const std::string& s)
{
stringstream ss;
ss << s;
string elem;
vector components;
while (getline(ss, elem, '|')) {
components.push_back(elem);
}
return components;
}
DabMultiplexer::DabMultiplexer(
boost::property_tree::ptree pt) :
RemoteControllable("mux"),
m_pt(pt),
ensemble(std::make_shared()),
m_clock_tai(split_pipe_separated_string(pt.get("general.tai_clock_bulletins", ""))),
fig_carousel(ensemble)
{
RC_ADD_PARAMETER(frames, "Show number of frames generated [read-only]");
RC_ADD_PARAMETER(tist_offset, "Timestamp offset in integral number of seconds");
rcs.enrol(&m_clock_tai);
}
DabMultiplexer::~DabMultiplexer()
{
rcs.remove_controllable(&m_clock_tai);
}
void DabMultiplexer::set_edi_config(const edi::configuration_t& new_edi_conf)
{
edi_conf = new_edi_conf;
edi_sender = make_shared(edi_conf);
}
// Run a set of checks on the configuration
void DabMultiplexer::prepare(bool require_tai_clock)
{
parse_ptree(m_pt, ensemble);
rcs.enrol(this);
rcs.enrol(ensemble.get());
prepare_subchannels();
prepare_services_components();
prepare_data_inputs();
if (not ensemble->validate_linkage_sets()) {
etiLog.log(error, "Linkage set definition error");
throw MuxInitException();
}
if (ensemble->subchannels.size() == 0) {
etiLog.log(error, "can't multiplex no subchannel!");
throw MuxInitException();
}
const auto last_subchannel = *(ensemble->subchannels.end() - 1);
if (last_subchannel->startAddress + last_subchannel->getSizeCu() > 864) {
etiLog.log(error, "Total size in CU exceeds 864");
printSubchannels(ensemble->subchannels);
throw MuxInitException();
}
/* At startup, derive edi_time, TIST and CIF count such that there is
* a consistency across mux restarts. Ensure edi_time and TIST represent
* current time.
*
* Every 6s, FCT overflows. m_currentFrame overflows at 5000 every 120s.
*
* Keep a granularity of 24ms, which corresponds to the duration of an ETI
* frame, to get nicer timestamps.
*/
using Sec = chrono::seconds;
const auto now = chrono::system_clock::now();
const time_t t_now = chrono::system_clock::to_time_t(chrono::time_point_cast(now));
m_edi_time = t_now - (t_now % 6);
m_currentFrame = 0;
time_t edi_time_at_cif0 = t_now - (t_now % 120);
while (edi_time_at_cif0 < m_edi_time) {
edi_time_at_cif0 += 6;
m_currentFrame += 250;
}
if (edi_time_at_cif0 != m_edi_time) {
throw std::logic_error("Invalid startup offset calculation for CIF!");
}
const auto offset = now - chrono::time_point_cast(now);
if (offset >= chrono::seconds(1)) {
throw std::logic_error("Invalid startup offset calculation for TIST! " +
to_string(chrono::duration_cast(offset).count()) +
" ms");
}
int64_t offset_ms = chrono::duration_cast(offset).count();
offset_ms += 1000 * (t_now - m_edi_time);
m_timestamp = 0;
while (offset_ms >= 24) {
increment_timestamp();
m_currentFrame++;
offset_ms -= 24;
}
etiLog.log(info, "Startup CIF Count %i with timestamp: %d + %f",
m_currentFrame, m_edi_time,
(m_timestamp & 0xFFFFFF) / 16384000.0);
// Try to load offset once
bool tist_enabled = m_pt.get("general.tist", false);
m_tist_offset = m_pt.get("general.tist_offset", 0);
m_tai_clock_required = (tist_enabled and edi_conf.enabled()) or require_tai_clock;
if (m_tai_clock_required) {
try {
m_clock_tai.get_offset();
}
catch (const std::runtime_error& e) {
etiLog.level(error) <<
"Could not initialise TAI clock properly. "
"TAI clock is required when TIST is enabled with an EDI output, "
"or when a ZMQ output with metadata is used. "
"Error: " << e.what();
throw;
}
}
if (ensemble->reconfig_counter == dabEnsemble::RECONFIG_COUNTER_HASH) {
vector data_to_hash;
data_to_hash.push_back(ensemble->id);
data_to_hash.push_back(ensemble->ecc);
for (const auto& srv : ensemble->services) {
data_to_hash.push_back(srv->id);
data_to_hash.push_back(srv->ecc);
}
for (const auto& sc : ensemble->components) {
data_to_hash.push_back(sc->serviceId);
data_to_hash.push_back(sc->subchId);
data_to_hash.push_back(sc->type);
data_to_hash.push_back(sc->SCIdS);
}
for (const auto& sub : ensemble->subchannels) {
data_to_hash.push_back(sub->id);
data_to_hash.push_back(sub->startAddress);
data_to_hash.push_back(sub->bitrate);
uint32_t t = 0;
switch (sub->type) {
case subchannel_type_t::DABAudio : t = 1; break;
case subchannel_type_t::DABPlusAudio: t = 2; break;
case subchannel_type_t::DataDmb: t = 3; break;
case subchannel_type_t::Packet: t= 4; break;
}
data_to_hash.push_back(t);
data_to_hash.push_back(sub->protection.to_tpl());
}
uint16_t crc_tmp = 0xFFFF;
crc_tmp = crc16(crc_tmp,
reinterpret_cast(data_to_hash.data()),
data_to_hash.size() * sizeof(data_to_hash.data()) / sizeof(uint16_t));
ensemble->reconfig_counter = crc_tmp % 1024;
etiLog.level(info) << "Calculated FIG 0/7 Count = " << ensemble->reconfig_counter;
}
}
// Check and adjust subchannels
void DabMultiplexer::prepare_subchannels()
{
set ids;
for (auto subchannel : ensemble->subchannels) {
if (ids.find(subchannel->id) != ids.end()) {
etiLog.log(error,
"Subchannel %u is set more than once!",
subchannel->id);
throw MuxInitException();
}
ids.insert(subchannel->id);
}
}
// Check and adjust services and components
void DabMultiplexer::prepare_services_components()
{
set ids;
dabProtection* protection = nullptr;
vec_sp_component::iterator component;
vec_sp_subchannel::iterator subchannel;
for (auto service : ensemble->services) {
if (ids.find(service->id) != ids.end()) {
etiLog.log(error,
"Service id 0x%x (%u) is set more than once!",
service->id, service->id);
throw MuxInitException();
}
// Get first component of this service
component = getComponent(ensemble->components, service->id);
if (component == ensemble->components.end()) {
etiLog.log(error,
"Service id 0x%x (%u) includes no component!",
service->id, service->id);
throw MuxInitException();
}
rcs.enrol(service.get());
// Adjust components type for DAB+
while (component != ensemble->components.end()) {
subchannel =
getSubchannel(ensemble->subchannels, (*component)->subchId);
if (subchannel == ensemble->subchannels.end()) {
etiLog.log(error, "Error, service %u component "
"links to the invalid subchannel %u",
(*component)->serviceId, (*component)->subchId);
throw MuxInitException();
}
protection = &(*subchannel)->protection;
switch ((*subchannel)->type) {
case subchannel_type_t::DABPlusAudio:
{
if (protection->form == EEP) {
/* According to ETSI TS 102 563 Clause 7.1 FIC signalling:
*
* "AAC audio services are signalled in the same way
* as Layer II audio services with the exception
* that the ASCTy carried in FIG 0/2 (see EN 300
* 401, clause 6.3.1) is set to the value
* 1 1 1 1 1 1."
*/
(*component)->type = 0x3f;
}
}
break;
case subchannel_type_t::DABAudio:
{
if (protection->form == EEP) {
/* ASCTy change to 0x0, because DAB mp2 is using
*/
(*component)->type = 0x0;
}
}
break;
case subchannel_type_t::DataDmb:
case subchannel_type_t::Packet:
break;
default:
etiLog.log(error,
"Error, unknown subchannel type");
throw MuxInitException();
}
component = getComponent(ensemble->components,
service->id, component);
}
}
// Init packet components SCId
int cur_packetid = 0;
for (auto component : ensemble->components) {
subchannel = getSubchannel(ensemble->subchannels,
component->subchId);
if (subchannel == ensemble->subchannels.end()) {
etiLog.log(error,
"Subchannel %i does not exist for component "
"of service %i",
component->subchId, component->serviceId);
throw MuxInitException();
}
if ((*subchannel)->type == subchannel_type_t::Packet) {
component->packet.id = cur_packetid++;
}
rcs.enrol(component.get());
}
}
void DabMultiplexer::prepare_data_inputs()
{
dabProtection* protection = nullptr;
// Prepare and check the data inputs
for (auto subchannel = ensemble->subchannels.begin();
subchannel != ensemble->subchannels.end();
++subchannel) {
protection = &(*subchannel)->protection;
if (subchannel == ensemble->subchannels.begin()) {
(*subchannel)->startAddress = 0;
} else {
(*subchannel)->startAddress = (*(subchannel - 1))->startAddress +
(*(subchannel - 1))->getSizeCu();
}
(*subchannel)->input->open((*subchannel)->inputUri);
// TODO Check errors
int subch_bitrate = (*subchannel)->input->setBitrate( (*subchannel)->bitrate);
if (subch_bitrate <= 0) {
etiLog.level(error) << "can't set bitrate for source " <<
(*subchannel)->inputUri;
throw MuxInitException();
}
(*subchannel)->bitrate = subch_bitrate;
/* Use EEP unless we find a UEP configuration
* UEP is only used for MPEG audio, but some bitrates don't
* have a UEP profile (EN 300 401 Clause 6.2.1).
* For these bitrates, we must switch to EEP.
*
* AAC audio and data is already EEP
*/
if (protection->form == UEP) {
protection->form = EEP;
for (int i = 0; i < 64; i++) {
if ( (*subchannel)->bitrate == BitRateTable[i] &&
protection->level == ProtectionLevelTable[i] ) {
protection->form = UEP;
protection->uep.tableIndex = i;
}
}
}
/* EEP B can only be used for subchannels with bitrates
* multiple of 32kbit/s
*/
if ( protection->form == EEP &&
protection->eep.profile == EEP_B &&
subch_bitrate % 32 != 0 ) {
etiLog.level(error) <<
"Cannot use EEP_B protection for subchannel " <<
(*subchannel)->inputUri <<
": bitrate not multiple of 32kbit/s";
throw MuxInitException();
}
}
}
void DabMultiplexer::increment_timestamp()
{
m_timestamp += 24 << 14; // Shift 24ms by 14 to Timestamp level 2
if (m_timestamp > 0xf9FFff) {
m_timestamp -= 0xfa0000; // Substract 16384000, corresponding to one second
m_edi_time += 1;
}
}
/* Each call creates one ETI frame */
void DabMultiplexer::mux_frame(std::vector >& outputs)
{
unsigned char etiFrame[6144];
unsigned short index = 0;
// FIC Length, DAB Mode I, II, IV -> FICL = 24, DAB Mode III -> FICL = 32
unsigned FICL =
(ensemble->transmission_mode == TransmissionMode_e::TM_III ? 32 : 24);
// For EDI, save ETI(LI) Management data into a TAG Item DETI
edi::TagDETI edi_tagDETI;
edi::TagStarPTR edi_tagStarPtr("DETI");
map edi_subchannelToTag;
// The above Tag Items will be assembled into a TAG Packet
edi::TagPacket edi_tagpacket(edi_conf.tagpacket_alignment);
const bool tist_enabled = m_pt.get("general.tist", false);
int tai_utc_offset = 0;
if (tist_enabled and m_tai_clock_required) {
try {
tai_utc_offset = m_clock_tai.get_offset();
}
catch (const std::runtime_error& e) {
etiLog.level(error) << "Could not get UTC-TAI offset for EDI timestamp";
}
}
update_dab_time();
const auto edi_time = m_edi_time + m_tist_offset;
// Initialise the ETI frame
memset(etiFrame, 0, 6144);
/**********************************************************************
********** Section SYNC of ETI(NI, G703) *************************
**********************************************************************/
// See ETS 300 799 Clause 6
eti_SYNC *etiSync = (eti_SYNC *) etiFrame;
etiSync->ERR = edi_tagDETI.stat = 0xFF; // ETS 300 799, 5.2, no error
//****** Field FSYNC *****//
// See ETS 300 799, 6.2.1.2
if ((m_currentFrame & 1) == 0) {
etiSync->FSYNC = ETI_FSYNC1;
}
else {
etiSync->FSYNC = ETI_FSYNC1 ^ 0xffffff;
}
/**********************************************************************
*********** Section LIDATA of ETI(NI, G703) **********************
**********************************************************************/
// See ETS 300 799 Figure 5 for a better overview of these fields.
//****** Section FC ***************************************************/
// 4 octets, starts at offset 4
eti_FC *fc = (eti_FC *) &etiFrame[4];
//****** FCT ******//
// Incremente for each frame, overflows at 249
fc->FCT = m_currentFrame % 250;
edi_tagDETI.dlfc = m_currentFrame % 5000;
//****** FICF ******//
// Fast Information Channel Flag, 1 bit, =1 if FIC present
fc->FICF = edi_tagDETI.ficf = 1;
//****** NST ******//
/* Number of audio of data sub-channels, 7 bits, 0-64.
* In the 15-frame period immediately preceding a multiplex
* re-configuration, NST can take the value 0 (see annex E).
*/
fc->NST = ensemble->subchannels.size();
//****** FP ******//
/* Frame Phase, 3 bit counter, tells the COFDM generator
* when to insert the TII. Is also used by the MNSC.
*/
fc->FP = edi_tagDETI.fp = m_currentFrame & 0x7;
//****** MID ******//
//Mode Identity, 2 bits, 01 ModeI, 10 modeII, 11 ModeIII, 00 ModeIV
switch (ensemble->transmission_mode) {
case TransmissionMode_e::TM_I:
fc->MID = edi_tagDETI.mid = 1;
break;
case TransmissionMode_e::TM_II:
fc->MID = edi_tagDETI.mid = 2;
break;
case TransmissionMode_e::TM_III:
fc->MID = edi_tagDETI.mid = 3;
break;
case TransmissionMode_e::TM_IV:
fc->MID = edi_tagDETI.mid = 0;
break;
}
//****** FL ******//
/* Frame Length, 11 bits, nb of words(4 bytes) in STC, EOH and MST
* if NST=0, FL=1+FICL words, FICL=24 or 32 depending on the mode.
* The FL is given in words (4 octets), see ETS 300 799 5.3.6 for details
*/
unsigned short FLtmp = 1 + FICL + (fc->NST);
for (auto subchannel = ensemble->subchannels.begin();
subchannel != ensemble->subchannels.end();
++subchannel) {
// Add STLsbch
FLtmp += (*subchannel)->getSizeWord();
}
fc->setFrameLength(FLtmp);
index = 8;
/******* Section STC **************************************************/
// Stream Characterization,
// number of channels * 4 octets = nb octets total
int edi_stream_id = 1;
for (auto subchannel : ensemble->subchannels) {
eti_STC *sstc = (eti_STC *) & etiFrame[index];
sstc->SCID = subchannel->id;
sstc->startAddress_high = subchannel->startAddress / 256;
sstc->startAddress_low = subchannel->startAddress % 256;
sstc->TPL = subchannel->protection.to_tpl();
// Sub-channel Stream Length, multiple of 64 bits
sstc->STL_high = subchannel->getSizeDWord() / 256;
sstc->STL_low = subchannel->getSizeDWord() % 256;
edi::TagESTn tag_ESTn;
tag_ESTn.id = edi_stream_id++;
tag_ESTn.scid = subchannel->id;
tag_ESTn.sad = subchannel->startAddress;
tag_ESTn.tpl = sstc->TPL;
tag_ESTn.rfa = 0; // two bits
tag_ESTn.mst_length = subchannel->getSizeByte() / 8;
tag_ESTn.mst_data = nullptr;
assert(subchannel->getSizeByte() % 8 == 0);
edi_subchannelToTag[subchannel.get()] = tag_ESTn;
index += 4;
}
/******* Section EOH **************************************************/
// End of Header 4 octets
eti_EOH *eoh = (eti_EOH *) & etiFrame[index];
//MNSC Multiplex Network Signalling Channel, 2 octets
eoh->MNSC = 0;
if (fc->FP == 0) {
// update the latched time only when FP==0 to ensure MNSC encodes
// a consistent time
m_edi_time_latched_for_mnsc = edi_time;
}
struct tm time_tm;
gmtime_r(&m_edi_time_latched_for_mnsc, &time_tm);
switch (fc->FP & 0x3) {
case 0:
{
eti_MNSC_TIME_0 *mnsc = (eti_MNSC_TIME_0 *) &eoh->MNSC;
// Set fields according to ETS 300 799 -- 5.5.1 and A.2.2
mnsc->type = 0;
mnsc->identifier = 0;
mnsc->rfa = 0;
}
break;
case 1:
{
eti_MNSC_TIME_1 *mnsc = (eti_MNSC_TIME_1 *) &eoh->MNSC;
mnsc->setFromTime(&time_tm);
mnsc->accuracy = 1;
mnsc->sync_to_frame = 1;
}
break;
case 2:
{
eti_MNSC_TIME_2 *mnsc = (eti_MNSC_TIME_2 *) &eoh->MNSC;
mnsc->setFromTime(&time_tm);
}
break;
case 3:
{
eti_MNSC_TIME_3 *mnsc = (eti_MNSC_TIME_3 *) &eoh->MNSC;
mnsc->setFromTime(&time_tm);
}
break;
}
edi_tagDETI.mnsc = eoh->MNSC;
// CRC Cyclic Redundancy Checksum of the FC, STC and MNSC, 2 octets
unsigned short nbBytesCRC = 4 + ((fc->NST) * 4) + 2;
unsigned short CRCtmp = 0xFFFF;
CRCtmp = crc16(CRCtmp, &etiFrame[4], nbBytesCRC);
CRCtmp ^= 0xffff;
eoh->CRC = htons(CRCtmp);
/******* Section MST **************************************************/
// Main Stream Data, if FICF=1 the first 96 or 128 bytes carry the FIC
// (depending on mode)
index = ((fc->NST) + 2 + 1) * 4;
edi_tagDETI.fic_data = &etiFrame[index];
edi_tagDETI.fic_length = FICL * 4;
// Insert all FIBs
fig_carousel.update(m_currentFrame);
const bool fib3_present = (ensemble->transmission_mode == TransmissionMode_e::TM_III);
index += fig_carousel.write_fibs(&etiFrame[index], m_currentFrame % 4, fib3_present);
/**********************************************************************
****** Input Data Reading *******************************************
**********************************************************************/
for (auto subchannel : ensemble->subchannels) {
edi::TagESTn& tag = edi_subchannelToTag[subchannel.get()];
int sizeSubchannel = subchannel->getSizeByte();
// no need to check enableTist because we always increment the timestamp
int result = subchannel->readFrame(&etiFrame[index],
sizeSubchannel, edi_time, tai_utc_offset, m_timestamp);
if (result < 0) {
etiLog.log(info,
"Subchannel %d read failed at ETI frame number: %d",
subchannel->id, m_currentFrame);
}
// save pointer to Audio or Data Stream into correct TagESTn for EDI
tag.mst_data = &etiFrame[index];
index += sizeSubchannel;
}
index = (3 + fc->NST + FICL) * 4;
for (auto subchannel : ensemble->subchannels) {
index += subchannel->getSizeByte();
}
/******* Section EOF **************************************************/
// End of Frame, 4 octets
index = (FLtmp + 1 + 1) * 4;
eti_EOF *eof = (eti_EOF *) & etiFrame[index];
// CRC of Main Stream data (MST), 16 bits
index = ((fc->NST) + 2 + 1) * 4; // MST position
unsigned short MSTsize = ((FLtmp) - 1 - (fc->NST)) * 4; // data size
CRCtmp = 0xffff;
CRCtmp = crc16(CRCtmp, &etiFrame[index], MSTsize);
CRCtmp ^= 0xffff;
eof->CRC = htons(CRCtmp);
//RFU, Reserved for future use, 2 bytes, should be 0xFFFF
eof->RFU = htons(0xFFFF);
/******* Section TIST *************************************************/
// TimeStamps, 24 bits + 1 octet
index = (FLtmp + 2 + 1) * 4;
eti_TIST *tist = (eti_TIST *) & etiFrame[index];
bool enableTist = m_pt.get("general.tist", false);
if (enableTist) {
tist->TIST = htonl(m_timestamp) | 0xff;
edi_tagDETI.tsta = m_timestamp & 0xffffff;
}
else {
tist->TIST = htonl(0xffffff) | 0xff;
edi_tagDETI.tsta = 0xffffff;
}
if (tist_enabled and m_tai_clock_required) {
edi_tagDETI.set_edi_time(edi_time, tai_utc_offset);
edi_tagDETI.atstf = true;
for (auto output : outputs) {
shared_ptr md_utco =
make_shared(edi_tagDETI.utco);
output->setMetadata(md_utco);
shared_ptr md_edi_time =
make_shared(edi_tagDETI.seconds);
output->setMetadata(md_edi_time);
shared_ptr md_dlfc =
make_shared(m_currentFrame % 5000);
output->setMetadata(md_dlfc);
}
}
/* Coding of the TIST, according to ETS 300 799 Annex C
Bit number b0(MSb)..b6 b7..b9 b10..b17 b18..b20 b21..b23(LSb)
Bit number b23(MSb)..b17 b16..b14 b13..b6 b5..b3 b2..b0(LSb)
as uint32_t
Width 7 3 8 3 3
Timestamp level 1 2 3 4 5
Valid range [0..124], 127 [0..7] [0..255] [0..7] [0..7]
Approximate 8 ms 1 ms 3,91 us 488 ns 61 ns
time resolution
*/
increment_timestamp();
/**********************************************************************
*********** Section FRPD *****************************************
**********************************************************************/
int frame_size = (FLtmp + 1 + 1 + 1 + 1) * 4;
for (auto output : outputs) {
auto out_zmq = std::dynamic_pointer_cast(output);
if (out_zmq) {
// The separator allows the receiver to associate the right
// metadata with the right ETI frame, since the output gathers
// four ETI frames into one message
shared_ptr md_sep =
make_shared();
out_zmq->setMetadata(md_sep);
}
}
// Give the data to the outputs
for (auto output : outputs) {
if (output->Write(etiFrame, frame_size) == -1) {
etiLog.level(error) <<
"Can't write to output " <<
output->get_info();
}
}
/**********************************************************************
*********** Finalise and send EDI ********************************
**********************************************************************/
if (edi_sender and edi_conf.enabled()) {
// put tags *ptr, DETI and all subchannels into one TagPacket
edi_tagpacket.tag_items.push_back(&edi_tagStarPtr);
edi_tagpacket.tag_items.push_back(&edi_tagDETI);
for (auto& tag : edi_subchannelToTag) {
edi_tagpacket.tag_items.push_back(&tag.second);
}
edi_sender->write(edi_tagpacket);
}
#if _DEBUG
/**********************************************************************
*********** Output a small message *********************************
**********************************************************************/
if (m_currentFrame % 100 == 0) {
if (enableTist) {
etiLog.log(info, "ETI frame number %i Timestamp: %d + %f",
m_currentFrame, edi_time,
(m_timestamp & 0xFFFFFF) / 16384000.0);
}
else {
etiLog.log(info, "ETI frame number %i Time: %d, no TIST",
m_currentFrame, edi_time);
}
}
#endif
m_currentFrame++;
}
void DabMultiplexer::print_info()
{
// Print settings before starting
printEnsemble(ensemble);
}
void DabMultiplexer::set_parameter(const std::string& parameter,
const std::string& value)
{
if (parameter == "frames") {
stringstream ss;
ss << "Parameter '" << parameter <<
"' of " << get_rc_name() <<
" is read-only";
throw ParameterError(ss.str());
}
else if (parameter == "tist_offset") {
m_tist_offset = std::stoi(value);
}
else {
stringstream ss;
ss << "Parameter '" << parameter <<
"' is not exported by controllable " << get_rc_name();
throw ParameterError(ss.str());
}
}
/* Getting a parameter always returns a string. */
const std::string DabMultiplexer::get_parameter(const std::string& parameter) const
{
stringstream ss;
if (parameter == "frames") {
ss << m_currentFrame;
}
else if (parameter == "tist_offset") {
ss << m_tist_offset;
}
else {
ss << "Parameter '" << parameter <<
"' is not exported by controllable " << get_rc_name();
throw ParameterError(ss.str());
}
return ss.str();
}