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ATV demod: new HSync process based on new horizontal sync code

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This commit is contained in:
f4exb 2020-07-22 07:52:21 +02:00
parent d240d1ae57
commit 432d6ed8fd
1 changed files with 86 additions and 65 deletions
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151
plugins/channelrx/demodatv/atvdemodsink.h
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@ -195,70 +195,6 @@ private:
void demod(Complex& c);
void applyStandard(int sampleRate, const ATVDemodSettings& settings, float lineDuration);
// Vertical sync is obtained by skipping horizontal sync on the line that triggers vertical sync (new frame)
inline void processHSkip(float& sample, int& sampleVideo)
{
// Fill pixel on the current line - column index 0 is reference at start of sync remove only sync length empirically
m_registeredTVScreen->setDataColor(m_colIndex - m_numberSamplesHSyncCrop, sampleVideo, sampleVideo, sampleVideo);
// Horizontal Synchro detection
// Floor Detection (0.1 nominal)
if (sample < m_settings.m_levelSynchroTop)
{
m_synchroSamples++;
}
// Black detection (0.3 nominal)
else if (sample > m_settings.m_levelBlack) {
m_synchroSamples = 0;
}
// H sync pulse
if (m_synchroSamples == m_numberSamplesPerHTop) // horizontal synchro detected
{
// Vertical sync and image rendering
if ((m_sampleIndex >= (3*m_samplesPerLine) / 2) // Vertical sync is first horizontal sync after skip (count at least 1.5 line length)
|| (!m_settings.m_vSync && (m_lineIndex >= m_settings.m_nbLines))) // Vsync ignored and reached nominal number of lines per frame
{
// qDebug("ATVDemodSink::processHSkip: %sVSync: co: %d sa: %d li: %d",
// (m_settings.m_vSync ? "" : "no "), m_colIndex, m_sampleIndex, m_lineIndex);
m_avgColIndex = m_colIndex;
m_registeredTVScreen->renderImage(0);
m_lineIndex = 0;
m_rowIndex = 0;
m_registeredTVScreen->selectRow(m_rowIndex);
}
m_sampleIndex = 0; // reset after H sync
}
else
{
m_sampleIndex++;
}
if (m_colIndex < m_samplesPerLine + m_numberSamplesPerHTop - 1) // increment until full line + next horizontal pulse
{
m_colIndex++;
}
else // full line + next horizontal pulse => start of screen reference line
{
// set column index to start a new line
if (m_settings.m_hSync && (m_lineIndex == 0)) { // start of a new frame - readjust sync position
m_colIndex = m_numberSamplesPerHTop + (m_samplesPerLine - m_avgColIndex) / 2; // amortizing factor 1/2
} else { // reset column index at end of sync pulse normally
m_colIndex = m_numberSamplesPerHTop;
}
m_lineIndex++; // new line
m_rowIndex++; // new row
if (m_rowIndex < m_settings.m_nbLines) {
m_registeredTVScreen->selectRow(m_rowIndex);
}
}
}
inline void processClassic(float& sample, int& sampleVideo)
{
// Filling pixel on the current line - reference index 0 at start of sync pulse
@ -271,7 +207,7 @@ private:
sample < m_settings.m_levelSynchroTop) // horizontal synchro detected
&& (m_sampleIndexDetected > m_samplesPerLine - m_numberSamplesPerHTopNom))
{
double sampleIndexDetectedFrac =
double sampleIndexDetectedFrac =
(sample - m_settings.m_levelSynchroTop) / (prevSample - sample);
double hSyncShift = -m_sampleIndex - sampleIndexDetectedFrac;
if (hSyncShift > m_samplesPerLine / 2)
@ -374,6 +310,91 @@ private:
prevSample = sample;
}
// Vertical sync is obtained by skipping horizontal sync on the line that triggers vertical sync (new frame)
inline void processHSkip(float& sample, int& sampleVideo)
{
// Filling pixel on the current line - reference index 0 at start of sync pulse
m_registeredTVScreen->setDataColor(m_sampleIndex - m_numberSamplesPerHSync, sampleVideo, sampleVideo, sampleVideo);
if (m_settings.m_hSync)
{
// Horizontal Synchro detection
if ((prevSample >= m_settings.m_levelSynchroTop &&
sample < m_settings.m_levelSynchroTop) // horizontal synchro detected
&& (m_sampleIndexDetected > m_samplesPerLine - m_numberSamplesPerHTopNom))
{
double sampleIndexDetectedFrac =
(sample - m_settings.m_levelSynchroTop) / (prevSample - sample);
double hSyncShift = -m_sampleIndex - sampleIndexDetectedFrac;
if (hSyncShift > m_samplesPerLine / 2)
hSyncShift -= m_samplesPerLine;
else if (hSyncShift < -m_samplesPerLine / 2)
hSyncShift += m_samplesPerLine;
if (fabs(hSyncShift) > m_numberSamplesPerHTopNom)
{
m_hSyncErrorCount++;
if (m_hSyncErrorCount >= 8)
{
// Fast sync: shift is too large, needs to be fixed ASAP
m_sampleIndex = 0;
m_hSyncShiftSum = 0.0;
m_hSyncShiftCount = 0;
m_hSyncErrorCount = 0;
}
}
else
{
m_hSyncShiftSum += hSyncShift;
m_hSyncShiftCount++;
m_hSyncErrorCount = 0;
}
m_sampleIndexDetected = 0;
}
else
m_sampleIndexDetected++;
}
else
{
m_hSyncShiftSum = 0.0f;
m_hSyncShiftCount = 0;
}
m_sampleIndex++;
// end of line
if (m_sampleIndex >= m_samplesPerLine)
{
m_sampleIndex = 0;
m_lineIndex++;
m_rowIndex++;
if ((m_sampleIndexDetected > (3*m_samplesPerLine) / 2) // Vertical sync is first horizontal sync after skip (count at least 1.5 line length)
|| (!m_settings.m_vSync && (m_lineIndex >= m_settings.m_nbLines))) // Vsync ignored and reached nominal number of lines per frame
{
float shiftSamples = 0.0f;
// Slow sync: slight adjustment is needed
if (m_hSyncShiftCount != 0 && m_settings.m_hSync)
{
shiftSamples = m_hSyncShiftSum / m_hSyncShiftCount;
m_sampleIndex = shiftSamples;
m_hSyncShiftSum = 0.0f;
m_hSyncShiftCount = 0;
m_hSyncErrorCount = 0;
}
m_registeredTVScreen->renderImage(0,
shiftSamples < -1.0f ? -1.0f : (shiftSamples > 1.0f ? 1.0f : shiftSamples));
m_lineIndex = 0;
m_rowIndex = 0;
}
m_registeredTVScreen->selectRow(m_rowIndex);
}
prevSample = sample;
}
};