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ATV Demod: further simplify horizontal sync and use exponential averaging to stabilize it

This commit is contained in:
f4exb 2017-03-29 02:23:03 +02:00
parent 2ef7dc3109
commit 3ab665142d
2 changed files with 40 additions and 52 deletions
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81
plugins/channelrx/demodatv/atvdemod.cpp
View File

@ -42,7 +42,6 @@ ATVDemod::ATVDemod(BasebandSampleSink* objScopeSink) :
m_blnSynchroDetected(false),
m_blnVerticalSynchroDetected(false),
m_intRowsLimit(0),
m_blnImageDetecting(false),
m_fltEffMin(2000000000.0f),
m_fltEffMax(-2000000000.0f),
m_fltAmpMin(-2000000000.0f),
@ -56,7 +55,8 @@ ATVDemod::ATVDemod(BasebandSampleSink* objScopeSink) :
m_interpolatorDistance(1.0f),
m_DSBFilter(0),
m_DSBFilterBuffer(0),
m_DSBFilterBufferIndex(0)
m_DSBFilterBufferIndex(0),
m_objAvgColIndex(2)
{
setObjectName("ATVDemod");
@ -445,7 +445,7 @@ void ATVDemod::demod(Complex& c)
if (blnComputeImage)
{
m_objRegisteredATVScreen->setDataColor(m_intColIndex - m_intNumberSamplePerTop, intVal, intVal, intVal); // TODO: the subtraction should be made with back porch number of samples
m_objRegisteredATVScreen->setDataColor(m_intColIndex - m_intNumberSaplesPerHSync + m_intNumberSamplePerTop, intVal, intVal, intVal); // TODO: the subtraction should be made with back porch number of samples
}
m_intColIndex++;
@ -454,46 +454,22 @@ void ATVDemod::demod(Complex& c)
m_blnSynchroDetected=false;
if((m_objRunning.m_blnHSync) && (m_intRowIndex>1))
if (m_intColIndex >= intSynchroTimeSamples)
{
//********** Line Synchro 0-0-0 -> 0.3-0.3 0.3 **********
if(m_blnImageDetecting==false)
//Floor Detection 0
if (fltVal <= m_objRunning.m_fltVoltLevelSynchroTop)
{
//Floor Detection 0
if (fltVal <= m_objRunning.m_fltVoltLevelSynchroTop)
{
m_intSynchroPoints ++;
}
else
{
m_intSynchroPoints=0;
}
if(m_intSynchroPoints>=m_intNumberSamplePerTop)
{
m_blnSynchroDetected=true;
m_blnImageDetecting=true;
m_intSynchroPoints=0;
}
m_intSynchroPoints++;
}
else
{
//Image detection Sub Black 0.3
if (fltVal >= m_objRunning.m_fltVoltLevelSynchroBlack)
{
m_intSynchroPoints ++;
}
else
{
m_intSynchroPoints=0;
}
m_intSynchroPoints = 0;
}
if(m_intSynchroPoints>=m_intNumberSamplePerTop)
{
m_blnSynchroDetected=false;
m_blnImageDetecting=false;
m_intSynchroPoints=0;
}
if (m_intSynchroPoints >= m_intNumberSamplePerTop)
{
m_blnSynchroDetected = true;
m_intSynchroPoints = 0;
}
}
@ -502,7 +478,7 @@ void ATVDemod::demod(Complex& c)
// Vertical Synchro : 3/4 a line necessary
if(!m_blnVerticalSynchroDetected && m_objRunning.m_blnVSync)
{
if(m_intColIndex>=intSynchroTimeSamples)
if(m_intColIndex >= intSynchroTimeSamples)
{
if(m_fltAmpLineAverage<=fltSynchroTrameLevel) //(m_fltLevelSynchroBlack*(float)(m_intColIndex-((m_intNumberSamplePerLine*12)/64)))) //75
{
@ -518,16 +494,24 @@ void ATVDemod::demod(Complex& c)
}
}
// TODO: stabilize horizontal sync by (exponential) averaging the column index at sync detection.
// Then on the next block trigger on this column index average.
//Horizontal Synchro
if((m_intColIndex>=m_intNumberSamplePerLine)
|| (m_blnSynchroDetected==true))
if ((m_blnSynchroDetected)
|| (m_intColIndex >= m_intNumberSamplePerLine + m_intNumberSamplePerTop)
|| (!m_objRunning.m_blnHSync && (m_intColIndex >= m_intNumberSamplePerLine)))
{
m_intColIndex=0;
m_blnImageDetecting=true;
m_blnSynchroDetected=false;
if (m_blnSynchroDetected
&& (m_intRowIndex > m_intNumberOfSyncLines)
&& (m_intColIndex > m_intNumberSamplePerLine - m_intNumberSamplePerTop)
&& (m_intColIndex < m_intNumberSamplePerLine + m_intNumberSamplePerTop))
{
m_intAvgColIndex = m_objAvgColIndex.run(m_intColIndex);
m_intColIndex = m_intColIndex - m_intAvgColIndex;
}
else
{
m_intColIndex = 0;
}
m_fltAmpLineAverage=0.0f;
//New line + Interleaving
@ -738,7 +722,7 @@ void ATVDemod::applySettings()
applyStandard();
m_objRegisteredATVScreen->resizeATVScreen(
m_intNumberSamplePerLine - (m_intNumberSamplePerTop+m_intNumberSamplePerEndOfLine),
m_intNumberSamplePerLine - m_intNumberSamplePerLineSignals,
m_intNumberOfLines - m_intNumberOfBlackLines);
qDebug() << "ATVDemod::applySettings:"
@ -826,7 +810,8 @@ void ATVDemod::applyStandard()
}
// for now all standards apply this
m_intNumberSamplePerEndOfLine = (int) ((7.3f/64.0f)*m_objConfig.m_fltLineDuration * m_objConfig.m_intSampleRate);
m_intNumberSamplePerLineSignals = (int) ((12.0f/64.0f)*m_objConfig.m_fltLineDuration * m_objConfig.m_intSampleRate); // 12.0 = 7.3 + 4.7
m_intNumberSaplesPerHSync = (int) ((9.4f/64.0f)*m_objConfig.m_fltLineDuration * m_objConfig.m_intSampleRate); // 9.4 = 4.7 + 4.7
}
int ATVDemod::getSampleRate()

11
plugins/channelrx/demodatv/atvdemod.h
View File

@ -339,9 +339,10 @@ private:
int m_intNumberSamplePerTop;
int m_intNumberOfLines;
int m_intNumberOfRowsToDisplay;
int m_intNumberOfSyncLines; //!< this is the number of non displayable lines at the start of a frame. First displayable row comes next.
int m_intNumberOfBlackLines; //!< this is the total number of lines not part of the image and is used for vertical screen size
int m_intNumberSamplePerEndOfLine;
int m_intNumberOfSyncLines; //!< this is the number of non displayable lines at the start of a frame. First displayable row comes next.
int m_intNumberOfBlackLines; //!< this is the total number of lines not part of the image and is used for vertical screen size
int m_intNumberSamplePerLineSignals; //!< number of samples in the non image part of the line (signals)
int m_intNumberSaplesPerHSync; //!< number of samples per horizontal synchronization pattern (pulse + back porch)
//*************** PROCESSING ***************
@ -350,7 +351,6 @@ private:
int m_intSynchroPoints;
bool m_blnSynchroDetected;
bool m_blnImageDetecting;
bool m_blnVerticalSynchroDetected;
float m_fltAmpLineAverage;
@ -368,6 +368,9 @@ private:
int m_intColIndex;
int m_intRowIndex;
AvgExpInt m_objAvgColIndex;
int m_intAvgColIndex;
//*************** RF ***************
MovingAverage<double> m_objMagSqAverage;