diff options
Diffstat (limited to 'src/DabMultiplexer.cpp')
| -rw-r--r-- | src/DabMultiplexer.cpp | 73 |
1 files changed, 52 insertions, 21 deletions
diff --git a/src/DabMultiplexer.cpp b/src/DabMultiplexer.cpp index fe7b156..a658262 100644 --- a/src/DabMultiplexer.cpp +++ b/src/DabMultiplexer.cpp @@ -99,25 +99,52 @@ void DabMultiplexer::prepare(bool require_tai_clock) throw MuxInitException(); } - /* Ensure edi_time and TIST represent current time. Keep - * a granularity of 24ms, which corresponds to the - * duration of an ETI frame, to get nicer timestamps. + /* 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(); - m_edi_time = chrono::system_clock::to_time_t(chrono::time_point_cast<Sec>(now)); - auto offset = now - chrono::time_point_cast<Sec>(now); + const time_t t_now = chrono::system_clock::to_time_t(chrono::time_point_cast<Sec>(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<Sec>(now); if (offset >= chrono::seconds(1)) { throw std::logic_error("Invalid startup offset calculation for TIST! " + to_string(chrono::duration_cast<chrono::milliseconds>(offset).count()) + " ms"); } + + int64_t offset_ms = chrono::duration_cast<chrono::milliseconds>(offset).count(); + offset_ms += 1000 * (t_now - m_edi_time); + m_timestamp = 0; - while (offset >= chrono::milliseconds(24)) { + while (offset_ms >= 24) { increment_timestamp(); - offset -= chrono::milliseconds(24); + 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); @@ -415,8 +442,12 @@ void DabMultiplexer::mux_frame(std::vector<std::shared_ptr<DabOutput> >& outputs //****** Field FSYNC *****// // See ETS 300 799, 6.2.1.2 - sync ^= 0xffffff; - etiSync->FSYNC = sync; + if ((m_currentFrame & 1) == 0) { + etiSync->FSYNC = ETI_FSYNC1; + } + else { + etiSync->FSYNC = ETI_FSYNC1 ^ 0xffffff; + } /********************************************************************** *********** Section LIDATA of ETI(NI, G703) ********************** @@ -430,8 +461,8 @@ void DabMultiplexer::mux_frame(std::vector<std::shared_ptr<DabOutput> >& outputs //****** FCT ******// // Incremente for each frame, overflows at 249 - fc->FCT = currentFrame % 250; - edi_tagDETI.dlfc = currentFrame % 5000; + fc->FCT = m_currentFrame % 250; + edi_tagDETI.dlfc = m_currentFrame % 5000; //****** FICF ******// // Fast Information Channel Flag, 1 bit, =1 if FIC present @@ -448,7 +479,7 @@ void DabMultiplexer::mux_frame(std::vector<std::shared_ptr<DabOutput> >& outputs /* 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 = currentFrame & 0x7; + fc->FP = edi_tagDETI.fp = m_currentFrame & 0x7; //****** MID ******// //Mode Identity, 2 bits, 01 ModeI, 10 modeII, 11 ModeIII, 00 ModeIV @@ -580,9 +611,9 @@ void DabMultiplexer::mux_frame(std::vector<std::shared_ptr<DabOutput> >& outputs edi_tagDETI.fic_length = FICL * 4; // Insert all FIBs - fig_carousel.update(currentFrame); + fig_carousel.update(m_currentFrame); const bool fib3_present = (ensemble->transmission_mode == TransmissionMode_e::TM_III); - index += fig_carousel.write_fibs(&etiFrame[index], currentFrame % 4, fib3_present); + index += fig_carousel.write_fibs(&etiFrame[index], m_currentFrame % 4, fib3_present); /********************************************************************** ****** Input Data Reading ******************************************* @@ -599,7 +630,7 @@ void DabMultiplexer::mux_frame(std::vector<std::shared_ptr<DabOutput> >& outputs if (result < 0) { etiLog.log(info, "Subchannel %d read failed at ETI frame number: %d", - subchannel->id, currentFrame); + subchannel->id, m_currentFrame); } // save pointer to Audio or Data Stream into correct TagESTn for EDI @@ -661,7 +692,7 @@ void DabMultiplexer::mux_frame(std::vector<std::shared_ptr<DabOutput> >& outputs output->setMetadata(md_edi_time); shared_ptr<OutputMetadata> md_dlfc = - make_shared<OutputMetadataDLFC>(currentFrame % 5000); + make_shared<OutputMetadataDLFC>(m_currentFrame % 5000); output->setMetadata(md_dlfc); } } @@ -726,20 +757,20 @@ void DabMultiplexer::mux_frame(std::vector<std::shared_ptr<DabOutput> >& outputs /********************************************************************** *********** Output a small message ********************************* **********************************************************************/ - if (currentFrame % 100 == 0) { + if (m_currentFrame % 100 == 0) { if (enableTist) { etiLog.log(info, "ETI frame number %i Timestamp: %d + %f", - currentFrame, edi_time, + m_currentFrame, edi_time, (m_timestamp & 0xFFFFFF) / 16384000.0); } else { etiLog.log(info, "ETI frame number %i Time: %d, no TIST", - currentFrame, edi_time); + m_currentFrame, edi_time); } } #endif - currentFrame++; + m_currentFrame++; } void DabMultiplexer::print_info() @@ -775,7 +806,7 @@ const std::string DabMultiplexer::get_parameter(const std::string& parameter) co { stringstream ss; if (parameter == "frames") { - ss << currentFrame; + ss << m_currentFrame; } else if (parameter == "tist_offset") { ss << m_tist_offset; |