/////////////////////////////////////////////////////////////////////////////////// // Copyright (C) 2019 Edouard Griffiths, F4EXB // // // // This program 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 as version 3 of the License, or // // (at your option) any later version. // // // // This program 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 V3 for more details. // // // // You should have received a copy of the GNU General Public License // // along with this program. If not, see . // /////////////////////////////////////////////////////////////////////////////////// #include #include #include #include #include "audio/audiooutput.h" #include "atvdemodsink.h" const int ATVDemodSink::m_ssbFftLen = 1024; ATVDemodSink::ATVDemodSink() : m_channelSampleRate(1000000), m_channelFrequencyOffset(0), m_tvSampleRate(1000000), m_samplesPerLine(100), m_videoTabIndex(0), m_scopeSink(nullptr), m_registeredTVScreen(nullptr), m_numberSamplesPerHTop(0), m_fieldIndex(0), m_synchroSamples(0), m_effMin(20.0f), m_effMax(-20.0f), m_ampMin(-1.0f), m_ampMax(1.0f), m_ampDelta(2.0f), m_colIndex(0), m_sampleIndex(0), m_sampleIndexDetected(0), m_hSyncShiftSum(0.0f), m_hSyncShiftCount(0), m_hSyncErrorCount(0), m_amSampleIndex(0), m_rowIndex(0), m_lineIndex(0), m_ampAverage(4800), m_bfoPLL(200/1000000, 100/1000000, 0.01), m_bfoFilter(200.0, 1000000.0, 0.9), m_interpolatorDistance(1.0f), m_interpolatorDistanceRemain(0.0f), m_DSBFilter(nullptr), m_DSBFilterBuffer(nullptr), m_DSBFilterBufferIndex(0) { qDebug("ATVDemodSink::ATVDemodSink"); //*************** ATV PARAMETERS *************** //m_intNumberSamplePerLine=0; m_synchroSamples=0; m_interleaved = true; m_DSBFilter = new fftfilt(m_settings.m_fftBandwidth / (float) m_tvSampleRate, 2*m_ssbFftLen); // arbitrary cutoff m_DSBFilterBuffer = new Complex[m_ssbFftLen]; std::fill(m_DSBFilterBuffer, m_DSBFilterBuffer + m_ssbFftLen, Complex{0.0, 0.0}); std::fill(m_fltBufferI, m_fltBufferI+6, 0.0f); std::fill(m_fltBufferQ, m_fltBufferQ+6, 0.0f); m_objPhaseDiscri.setFMScaling(1.0f); applySettings(m_settings, true); applyChannelSettings(m_channelSampleRate, m_channelFrequencyOffset, true); } ATVDemodSink::~ATVDemodSink() { delete m_DSBFilter; delete[] m_DSBFilterBuffer; } void ATVDemodSink::feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end) { //********** Let's rock and roll buddy ! ********** //********** Accessing ATV Screen context ********** for (SampleVector::const_iterator it = begin; it != end; ++it /* ++it **/) { Complex c(it->real(), it->imag()); if (m_settings.m_inputFrequencyOffset != 0) { c *= m_nco.nextIQ(); } if ((m_tvSampleRate == m_channelSampleRate) && (!m_settings.m_forceDecimator)) // no decimation { demod(c); } else { Complex ci; if (m_interpolator.decimate(&m_interpolatorDistanceRemain, c, &ci)) { demod(ci); m_interpolatorDistanceRemain += m_interpolatorDistance; } } } if ((m_videoTabIndex == 1) && (m_scopeSink)) // do only if scope tab is selected and scope is available { m_scopeSink->feed(m_scopeSampleBuffer.begin(), m_scopeSampleBuffer.end(), false); // m_ssb = positive only m_scopeSampleBuffer.clear(); } } void ATVDemodSink::demod(Complex& c) { float sampleNormI; float sampleNormQ; float sampleNorm; float sample; int sampleVideo; //********** FFT filtering ********** if (m_settings.m_fftFiltering) { int n_out; Complex *filtered; n_out = m_DSBFilter->runAsym(c, &filtered, m_settings.m_atvModulation != ATVDemodSettings::ATV_LSB); // all usb except explicitely lsb if (n_out > 0) { std::copy(filtered, filtered + n_out, m_DSBFilterBuffer); m_DSBFilterBufferIndex = 0; } else if (m_DSBFilterBufferIndex < m_ssbFftLen - 1) // safe { m_DSBFilterBufferIndex++; } } //********** demodulation ********** float fftScale = 1.0f; const float& fltI = m_settings.m_fftFiltering ? m_DSBFilterBuffer[m_DSBFilterBufferIndex].real() : c.real(); const float& fltQ = m_settings.m_fftFiltering ? m_DSBFilterBuffer[m_DSBFilterBufferIndex].imag() : c.imag(); double magSq; if ((m_settings.m_atvModulation == ATVDemodSettings::ATV_FM1) || (m_settings.m_atvModulation == ATVDemodSettings::ATV_FM2)) { //Amplitude FM magSq = fltI*fltI + fltQ*fltQ; m_magSqAverage(magSq); sampleNorm = sqrt(magSq); sampleNormI = fltI/sampleNorm; sampleNormQ = fltQ/sampleNorm; //-2 > 2 : 0 -> 1 volt //0->0.3 synchro 0.3->1 image if (m_settings.m_atvModulation == ATVDemodSettings::ATV_FM1) { //YDiff Cd sample = m_fltBufferI[0]*(sampleNormQ - m_fltBufferQ[1]); sample -= m_fltBufferQ[0]*(sampleNormI - m_fltBufferI[1]); sample += 2.0f; sample /= 4.0f; } else { //YDiff Folded sample = m_fltBufferI[2]*((m_fltBufferQ[5]-sampleNormQ)/16.0f + m_fltBufferQ[1] - m_fltBufferQ[3]); sample -= m_fltBufferQ[2]*((m_fltBufferI[5]-sampleNormI)/16.0f + m_fltBufferI[1] - m_fltBufferI[3]); sample += 2.125f; sample /= 4.25f; m_fltBufferI[5] = m_fltBufferI[4]; m_fltBufferQ[5] = m_fltBufferQ[4]; m_fltBufferI[4] = m_fltBufferI[3]; m_fltBufferQ[4] = m_fltBufferQ[3]; m_fltBufferI[3] = m_fltBufferI[2]; m_fltBufferQ[3] = m_fltBufferQ[2]; m_fltBufferI[2] = m_fltBufferI[1]; m_fltBufferQ[2] = m_fltBufferQ[1]; } m_fltBufferI[1] = m_fltBufferI[0]; m_fltBufferQ[1] = m_fltBufferQ[0]; m_fltBufferI[0] = sampleNormI; m_fltBufferQ[0] = sampleNormQ; if (m_settings.m_fmDeviation != 1.0f) { sample = ((sample - 0.5f) / m_settings.m_fmDeviation) + 0.5f; } } else if (m_settings.m_atvModulation == ATVDemodSettings::ATV_AM) { //Amplitude AM magSq = fltI*fltI + fltQ*fltQ; m_magSqAverage(magSq); sampleNorm = sqrt(magSq); float sampleRaw = sampleNorm / SDR_RX_SCALEF; m_ampAverage(sampleRaw); sample = sampleRaw / (2.0f * m_ampAverage.asFloat()); // AGC } else if ((m_settings.m_atvModulation == ATVDemodSettings::ATV_USB) || (m_settings.m_atvModulation == ATVDemodSettings::ATV_LSB)) { magSq = fltI*fltI + fltQ*fltQ; m_magSqAverage(magSq); sampleNorm = sqrt(magSq); Real bfoValues[2]; float fltFiltered = m_bfoFilter.run(fltI); m_bfoPLL.process(fltFiltered, bfoValues); // do the mix float mixI = fltI * bfoValues[0] - fltQ * bfoValues[1]; float mixQ = fltI * bfoValues[1] + fltQ * bfoValues[0]; if (m_settings.m_atvModulation == ATVDemodSettings::ATV_USB) { sample = (mixI + mixQ); } else { sample = (mixI - mixQ); } } else if (m_settings.m_atvModulation == ATVDemodSettings::ATV_FM3) { float rawDeviation; sample = m_objPhaseDiscri.phaseDiscriminatorDelta(c, magSq, rawDeviation) + 0.5f; m_magSqAverage(magSq); sampleNorm = sqrt(magSq); } else { magSq = fltI*fltI + fltQ*fltQ; m_magSqAverage(magSq); sampleNorm = sqrt(magSq); sample = 0.0f; } //********** AM sample normalization and coarse scale estimation ********** if ((m_settings.m_atvModulation == ATVDemodSettings::ATV_AM) || (m_settings.m_atvModulation == ATVDemodSettings::ATV_USB) || (m_settings.m_atvModulation == ATVDemodSettings::ATV_LSB)) { // Mini and Maxi Amplitude tracking if (sample < m_effMin) { m_effMin = sample; } if (sample > m_effMax) { m_effMax = sample; } if (m_amSampleIndex < m_samplesPerLine * m_settings.m_nbLines * 2) // calculate on two full images { m_amSampleIndex++; } else { // scale signal based on extrema on the estimation period m_ampMin = m_effMin; m_ampMax = m_effMax; m_ampDelta = (m_ampMax - m_ampMin); if (m_ampDelta <= 0.0) { m_ampDelta = 1.0f; } // readjustment m_ampDelta /= m_settings.m_amScalingFactor / 100.0f; m_ampMin += m_ampDelta * (m_settings.m_amOffsetFactor / 100.0f); // qDebug("ATVDemod::demod: m_ampMin: %f m_ampMax: %f m_ampDelta: %f", m_ampMin, m_ampMax, m_ampDelta); //Reset extrema m_effMin = 20.0f; m_effMax = -20.0f; m_amSampleIndex = 0; } //Normalisation of current sample sample -= m_ampMin; sample /= m_ampDelta; } sample = m_settings.m_invertVideo ? 1.0f - sample : sample; // 0.0 -> 1.0 sample = (sample < 0.0f) ? 0.0f : (sample > 1.0f) ? 1.0f : sample; if ((m_videoTabIndex == 1) && (m_scopeSink != 0)) { // feed scope buffer only if scope is present and visible m_scopeSampleBuffer.push_back(Sample(sample * (SDR_RX_SCALEF - 1.0f), 0.0f)); } //********** gray level ********** // -0.3 -> 0.7 / 0.7 sampleVideo = (int) ((sample - m_settings.m_levelBlack) * m_sampleRangeCorrection); // 0 -> 255 sampleVideo = (sampleVideo < 0) ? 0 : (sampleVideo > 255) ? 255 : sampleVideo; //********** process video sample ********** if (m_registeredTVScreen) // can process only if the screen is available (set via the GUI) { if (m_settings.m_atvStd == ATVDemodSettings::ATVStdHSkip) { processHSkip(sample, sampleVideo); } else { processClassic(sample, sampleVideo); } } } void ATVDemodSink::applyStandard(int sampleRate, const ATVDemodSettings& settings, float lineDuration) { switch(settings.m_atvStd) { case ATVDemodSettings::ATVStdHSkip: // what is left in a line for the image m_interleaved = false; // irrelevant m_numberOfBlackLines = 0; m_numberSamplesHSyncCrop = (int) (0.09f * lineDuration * sampleRate); // 9% of full line empirically break; case ATVDemodSettings::ATVStdShort: // what is left in a line for the image m_interleaved = false; m_numberOfVSyncLines = 2; m_numberOfBlackLines = 4; m_firstVisibleLine = 3; m_numberSamplesHSyncCrop = (int) (0.085f * lineDuration * sampleRate); // 8.5% of full line empirically break; case ATVDemodSettings::ATVStdShortInterleaved: // what is left in a line for the image m_interleaved = true; m_numberOfVSyncLines = 2; m_numberOfBlackLines = 5; m_firstVisibleLine = 3; m_numberSamplesHSyncCrop = (int) (0.085f * lineDuration * sampleRate); // 8.5% of full line empirically break; case ATVDemodSettings::ATVStd405: // Follows loosely the 405 lines standard // what is left in a line for the image m_interleaved = true; m_numberOfVSyncLines = 3; m_numberOfBlackLines = 30; m_firstVisibleLine = 13; m_numberSamplesHSyncCrop = (int) (0.085f * lineDuration * sampleRate); // 8.5% of full line empirically break; case ATVDemodSettings::ATVStdPAL525: // Follows PAL-M standard // what is left in a 64/1.008 us line for the image m_interleaved = true; m_numberOfVSyncLines = 4; m_numberOfBlackLines = 45; m_firstVisibleLine = 20; m_numberSamplesHSyncCrop = (int) (0.085f * lineDuration * sampleRate); // 8.5% of full line empirically break; case ATVDemodSettings::ATVStdPAL625: // Follows PAL-B/G/H standard default: // what is left in a 64 us line for the image m_interleaved = true; m_numberOfVSyncLines = 3; m_numberOfBlackLines = 49; m_firstVisibleLine = 23; m_numberSamplesHSyncCrop = (int) (0.085f * lineDuration * sampleRate); // 8.5% of full line empirically } // for now all standards apply this // Rec. ITU-R BT.1700 // Table 2. Details of line synchronizing signals m_numberSamplesPerLineSignals = (int)(lineDuration * sampleRate * 12.0 / 64.0); // "a", Line-blanking interval m_numberSamplesPerHSync = (int)(lineDuration * sampleRate * 10.5 / 64.0); // "b", Interval between time datum and back edge of line-blanking pulse m_numberSamplesPerHTopNom = (int)(lineDuration * sampleRate * 4.7 / 64.0); // "d", Duration of synchronizing pulse // Table 3. Details of field synchronizing signals float hl = 32.0f; // half of the line float p = 2.35f; // "p", Duration of equalizing pulse float q = 27.3f; // "q", Duration of field-synchronizing pulse // In the first half of the first line field index is detected m_fieldDetectStartPos = (int)(lineDuration * sampleRate * p / 64.0); m_fieldDetectEndPos = (int)(lineDuration * sampleRate * q / 64.0); // In the second half of the first line vertical synchronization is detected m_vSyncDetectStartPos = (int)(lineDuration * sampleRate * (p + hl) / 64.0); m_vSyncDetectEndPos = (int)(lineDuration * sampleRate * (q + hl) / 64.0); float fieldDetectPercent = 0.75f; // It is better not to detect field index than detect it wrong float detectTotalLen = lineDuration * sampleRate * (q - p) / 64.0; // same for field index and vSync detection m_fieldDetectThreshold1 = (int)(detectTotalLen * fieldDetectPercent); m_fieldDetectThreshold2 = (int)(detectTotalLen * (1.0f - fieldDetectPercent)); float vSyncDetectPercent = 0.5f; m_vSyncDetectThreshold = (int)(detectTotalLen * vSyncDetectPercent); m_numberSamplesPerHTop = m_numberSamplesPerHTopNom * (settings.m_topTimeFactor / 100.0f); // adjust the value used in the system } bool ATVDemodSink::getBFOLocked() { if ((m_settings.m_atvModulation == ATVDemodSettings::ATV_USB) || (m_settings.m_atvModulation == ATVDemodSettings::ATV_LSB)) { return m_bfoPLL.locked(); } else { return false; } } void ATVDemodSink::applyChannelSettings(int channelSampleRate, int channelFrequencyOffset, bool force) { qDebug() << "ATVDemodSink::applyChannelSettings:" << " channelSampleRate: " << channelSampleRate << " channelFrequencyOffset: " << channelFrequencyOffset; if (channelSampleRate == 0) { qDebug("ATVDemodSink::applyChannelSettings: aborting"); return; } if ((channelFrequencyOffset != m_channelFrequencyOffset) || (channelSampleRate != m_channelSampleRate) || force) { m_nco.setFreq(-channelFrequencyOffset, channelSampleRate); } if ((channelSampleRate != m_channelSampleRate) || force) { unsigned int samplesPerLineNom; ATVDemodSettings::getBaseValues(channelSampleRate, m_settings.m_nbLines * m_settings.m_fps, m_tvSampleRate, samplesPerLineNom); m_samplesPerLine = samplesPerLineNom + m_settings.m_lineTimeFactor; qDebug() << "ATVDemodSink::applyChannelSettings:" << " m_tvSampleRate: " << m_tvSampleRate << " m_fftBandwidth: " << m_settings.m_fftBandwidth << " m_fftOppBandwidth:" << m_settings.m_fftOppBandwidth << " m_bfoFrequency: " << m_settings.m_bfoFrequency; if (m_tvSampleRate > 0) { m_interpolatorDistanceRemain = 0; m_interpolatorDistance = (Real) m_tvSampleRate / (Real) channelSampleRate; m_interpolator.create(24, m_tvSampleRate, m_settings.m_fftBandwidth / ATVDemodSettings::getRFBandwidthDivisor(m_settings.m_atvModulation), 3.0 ); } else { m_tvSampleRate = channelSampleRate; } m_DSBFilter->create_asym_filter( m_settings.m_fftOppBandwidth / (float) m_tvSampleRate, m_settings.m_fftBandwidth / (float) m_tvSampleRate ); std::fill(m_DSBFilterBuffer, m_DSBFilterBuffer + m_ssbFftLen, Complex{0.0, 0.0}); m_DSBFilterBufferIndex = 0; m_bfoPLL.configure((float) m_settings.m_bfoFrequency / (float) m_tvSampleRate, 100.0 / m_tvSampleRate, 0.01); m_bfoFilter.setFrequencies(m_tvSampleRate, m_settings.m_bfoFrequency); } applyStandard(m_tvSampleRate, m_settings, ATVDemodSettings::getNominalLineTime(m_settings.m_nbLines, m_settings.m_fps)); if (m_registeredTVScreen) { m_registeredTVScreen->resizeTVScreen( m_samplesPerLine - m_numberSamplesPerLineSignals, m_settings.m_nbLines - m_numberOfBlackLines ); } m_fieldIndex = 0; m_colIndex = 0; m_rowIndex = 0; m_channelSampleRate = channelSampleRate; m_channelFrequencyOffset = channelFrequencyOffset; } void ATVDemodSink::applySettings(const ATVDemodSettings& settings, bool force) { qDebug() << "ATVDemodSink::applySettings:" << "m_inputFrequencyOffset:" << settings.m_inputFrequencyOffset << "m_forceDecimator:" << settings.m_forceDecimator << "m_bfoFrequency:" << settings.m_bfoFrequency << "m_atvModulation:" << settings.m_atvModulation << "m_fmDeviation:" << settings.m_fmDeviation << "m_fftFiltering:" << settings.m_fftFiltering << "m_fftOppBandwidth:" << settings.m_fftOppBandwidth << "m_fftBandwidth:" << settings.m_fftBandwidth << "m_nbLines:" << settings.m_nbLines << "m_fps:" << settings.m_fps << "m_atvStd:" << settings.m_atvStd << "m_hSync:" << settings.m_hSync << "m_vSync:" << settings.m_vSync << "m_invertVideo:" << settings.m_invertVideo << "m_halfFrames:" << settings.m_halfFrames << "m_levelSynchroTop:" << settings.m_levelSynchroTop << "m_levelBlack:" << settings.m_levelBlack << "m_lineTimeFactor:" << settings.m_lineTimeFactor << "m_topTimeFactor:" << settings.m_topTimeFactor << "m_rgbColor:" << settings.m_rgbColor << "m_title:" << settings.m_title << "m_udpAddress:" << settings.m_udpAddress << "m_udpPort:" << settings.m_udpPort << "force:" << force; if ((settings.m_nbLines != m_settings.m_nbLines) || (settings.m_fps != m_settings.m_fps) || (settings.m_atvStd != m_settings.m_atvStd) || (settings.m_atvModulation != m_settings.m_atvModulation) || (settings.m_fftBandwidth != m_settings.m_fftBandwidth) || (settings.m_fftOppBandwidth != m_settings.m_fftOppBandwidth) || (settings.m_atvStd != m_settings.m_atvStd) || (settings.m_lineTimeFactor != m_settings.m_lineTimeFactor) || force) { unsigned int samplesPerLineNom; ATVDemodSettings::getBaseValues(m_channelSampleRate, settings.m_nbLines * settings.m_fps, m_tvSampleRate, samplesPerLineNom); m_samplesPerLine = samplesPerLineNom + settings.m_lineTimeFactor; m_ampAverage.resize(m_samplesPerLine * m_settings.m_nbLines * 2); // AGC average in two full images qDebug() << "ATVDemodSink::applySettings:" << " m_tvSampleRate: " << m_tvSampleRate << " m_fftBandwidth: " << settings.m_fftBandwidth << " m_fftOppBandwidth:" << settings.m_fftOppBandwidth << " m_bfoFrequency: " << settings.m_bfoFrequency; if (m_tvSampleRate > 0) { m_interpolatorDistanceRemain = 0; m_interpolatorDistance = (Real) m_tvSampleRate / (Real) m_channelSampleRate; m_interpolator.create(24, m_tvSampleRate, settings.m_fftBandwidth / ATVDemodSettings::getRFBandwidthDivisor(settings.m_atvModulation), 3.0 ); } else { m_tvSampleRate = m_channelSampleRate; } m_DSBFilter->create_asym_filter( settings.m_fftOppBandwidth / (float) m_tvSampleRate, settings.m_fftBandwidth / (float) m_tvSampleRate ); std::fill(m_DSBFilterBuffer, m_DSBFilterBuffer + m_ssbFftLen, Complex{0.0, 0.0}); m_DSBFilterBufferIndex = 0; m_bfoPLL.configure((float) settings.m_bfoFrequency / (float) m_tvSampleRate, 100.0 / m_tvSampleRate, 0.01); m_bfoFilter.setFrequencies(m_tvSampleRate, settings.m_bfoFrequency); applyStandard(m_tvSampleRate, settings, ATVDemodSettings::getNominalLineTime(settings.m_nbLines, settings.m_fps)); if (m_registeredTVScreen) { m_registeredTVScreen->resizeTVScreen( m_samplesPerLine - m_numberSamplesPerLineSignals, m_settings.m_nbLines - m_numberOfBlackLines ); } m_fieldIndex = 0; m_colIndex = 0; m_rowIndex = 0; } if ((settings.m_topTimeFactor != m_settings.m_topTimeFactor) || force) { m_numberSamplesPerHTop = m_numberSamplesPerHTopNom * (settings.m_topTimeFactor / 100.0f); } if ((settings.m_fmDeviation != m_settings.m_fmDeviation) || force) { m_objPhaseDiscri.setFMScaling(1.0f / settings.m_fmDeviation); } if ((settings.m_levelBlack != m_settings.m_levelBlack) || force) { m_sampleRangeCorrection = 255.0f / (1.0f - m_settings.m_levelBlack); } m_settings = settings; }