Sample offset is adjusted every line

plugins/channelrx/demodatv/atvdemodsink.cpp

@@ -43,14 +43,12 @@ ATVDemodSink::ATVDemodSink() :
     m_ampMin(-1.0f),
     m_ampMax(1.0f),
     m_ampDelta(2.0f),
-    m_colIndex(0),
+    m_sampleOffset(0),
-    m_sampleIndex(0),
+	m_sampleOffsetFrac(0.0f),
-    m_sampleIndexDetected(0),
+    m_sampleOffsetDetected(0),
-    m_hSyncShiftSum(0.0f),
+	m_hSyncShift(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),
@@ -490,8 +488,6 @@ void ATVDemodSink::applyChannelSettings(int channelSampleRate, int channelFreque
     }
 
     m_fieldIndex = 0;
-    m_colIndex = 0;
-    m_rowIndex = 0;
 
     m_channelSampleRate = channelSampleRate;
     m_channelFrequencyOffset = channelFrequencyOffset;
@@ -584,8 +580,6 @@ void ATVDemodSink::applySettings(const ATVDemodSettings& settings, bool force)
         }
 
         m_fieldIndex = 0;
-        m_colIndex = 0;
-        m_rowIndex = 0;
     }
 
     if ((settings.m_topTimeFactor != m_settings.m_topTimeFactor) || force) {

plugins/channelrx/demodatv/atvdemodsink.h

@@ -150,15 +150,14 @@ private:
     float m_fltBufferI[6];
     float m_fltBufferQ[6];
 
-    int m_colIndex;
-    int m_sampleIndex;         // assumed (averaged) sample offset from the start of horizontal sync pulse
-    int m_sampleIndexDetected; // detected sample offset from the start of horizontal sync pulse
 	int m_amSampleIndex;
-    int m_rowIndex;
+
+    int m_sampleOffset;         // assumed (averaged) sample offset from the start of horizontal sync pulse
+	float m_sampleOffsetFrac;   // sample offset, fractional part
+    int m_sampleOffsetDetected; // detected sample offset from the start of horizontal sync pulse
     int m_lineIndex;
 
-    float m_hSyncShiftSum;
+	float m_hSyncShift;
-    int m_hSyncShiftCount;
     int m_hSyncErrorCount;
 
     float prevSample;
@@ -200,18 +199,18 @@ private:
     inline void processSample(float& sample, int& sampleVideo)
     {
         // Filling pixel on the current line - reference index 0 at start of sync pulse
-		m_tvScreenData->setSampleValue(m_sampleIndex - m_numberSamplesPerHSync, sampleVideo);
+		m_tvScreenData->setSampleValue(m_sampleOffset - m_numberSamplesPerHSync, 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))
+                && (m_sampleOffsetDetected > m_samplesPerLine - m_numberSamplesPerHTopNom))
             {
-                double sampleIndexDetectedFrac =
+                float sampleOffsetDetectedFrac =
                     (sample - m_settings.m_levelSynchroTop) / (prevSample - sample);
-                double hSyncShift = -m_sampleIndex - sampleIndexDetectedFrac;
+                float hSyncShift = -m_sampleOffset - m_sampleOffsetFrac - sampleOffsetDetectedFrac;
                 if (hSyncShift > m_samplesPerLine / 2)
 					hSyncShift -= m_samplesPerLine;
                 else if (hSyncShift < -m_samplesPerLine / 2)
@@ -220,46 +219,50 @@ private:
                 if (fabs(hSyncShift) > m_numberSamplesPerHTopNom)
                 {
                     m_hSyncErrorCount++;
-                    if (m_hSyncErrorCount >= 8)
+                    if (m_hSyncErrorCount >= 4)
                     {
                         // Fast sync: shift is too large, needs to be fixed ASAP
-                        m_sampleIndex = 0;
+						m_hSyncShift = hSyncShift;
-                        m_hSyncShiftSum = 0.0;
-                        m_hSyncShiftCount = 0;
                         m_hSyncErrorCount = 0;
                     }
                 }
                 else
                 {
-                    m_hSyncShiftSum += hSyncShift;
+					// Slow sync: slight adjustment is needed
-                    m_hSyncShiftCount++;
+					m_hSyncShift = hSyncShift * 0.2f;
                     m_hSyncErrorCount = 0;
                 }
-                m_sampleIndexDetected = 0;
+				m_sampleOffsetDetected = 0;
             }
             else
-                m_sampleIndexDetected++;
+				m_sampleOffsetDetected++;
         }
-        else
+		m_sampleOffset++;
-        {
-            m_hSyncShiftSum = 0.0f;
-            m_hSyncShiftCount = 0;
-        }
-        m_sampleIndex++;
 
         if (m_settings.m_vSync)
         {
-            if (m_sampleIndex > m_fieldDetectStartPos && m_sampleIndex < m_fieldDetectEndPos)
+            if (m_sampleOffset > m_fieldDetectStartPos && m_sampleOffset < m_fieldDetectEndPos)
                 m_fieldDetectSampleCount += sample < m_settings.m_levelSynchroTop;
-            if (m_sampleIndex > m_vSyncDetectStartPos && m_sampleIndex < m_vSyncDetectEndPos)
+            if (m_sampleOffset > m_vSyncDetectStartPos && m_sampleOffset < m_vSyncDetectEndPos)
                 m_vSyncDetectSampleCount += sample < m_settings.m_levelSynchroTop;
         }
 
         // end of line
-        if (m_sampleIndex >= m_samplesPerLine)
+        if (m_sampleOffset >= m_samplesPerLine)
         {
-            m_sampleIndex = 0;
+			if (m_settings.m_hSync)
+			{
+				float sampleOffsetFloat = m_hSyncShift + m_sampleOffsetFrac;
+				m_sampleOffset = sampleOffsetFloat;
+				m_sampleOffsetFrac = sampleOffsetFloat - m_sampleOffset;
+			}
+			else
+			{
+				m_sampleOffset = 0;
+			}
+			m_hSyncShift = 0.0f;
 
+			m_lineIndex++;
 			if (m_settings.m_atvStd == ATVDemodSettings::ATVStdHSkip) {
                 processEOLHSkip();
             } else {
@@ -273,24 +276,9 @@ private:
     // Standard vertical sync
     inline void processEOLClassic()
     {
-        m_lineIndex++;
-
         if (m_lineIndex == m_numberOfVSyncLines + 3 && m_fieldIndex == 0)
         {
-            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();
-            //m_registeredTVScreen->renderImage(0,
-            //    shiftSamples < -1.0f ? -1.0f : (shiftSamples > 1.0f ? 1.0f : shiftSamples));
         }
 
         if (m_vSyncDetectSampleCount > m_vSyncDetectThreshold &&
@@ -323,47 +311,21 @@ private:
         if (m_interleaved)
             rowIndex = rowIndex * 2 - m_fieldIndex;
 
-		// TODO: CHANGE
+		m_tvScreenData->selectRow(rowIndex, m_sampleOffsetFrac);
-		float shiftSamples = 0.0f;
-		if (m_hSyncShiftCount != 0)
-			shiftSamples = m_hSyncShiftSum / m_hSyncShiftCount;
-		m_tvScreenData->selectRow(rowIndex,
-			shiftSamples < -1.0f ? -1.0f : (shiftSamples > 1.0f ? 1.0f : shiftSamples));
 	}
 
     // Vertical sync is obtained by skipping horizontal sync on the line that triggers vertical sync (new frame)
     inline void processEOLHSkip()
     {
-        m_lineIndex++;
+		if ((m_sampleOffsetDetected > (3 * m_samplesPerLine) / 2) // Vertical sync is first horizontal sync after skip (count at least 1.5 line length)
-        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();
-            //m_registeredTVScreen->renderImage(0,
-            //    shiftSamples < -1.0f ? -1.0f : (shiftSamples > 1.0f ? 1.0f : shiftSamples));
 			m_lineIndex = 0;
-            m_rowIndex = 0;
         }
 
-		// TODO: CHANGE
+		m_tvScreenData->selectRow(m_lineIndex, m_sampleOffsetFrac);
-		float shiftSamples = m_hSyncShiftSum / m_hSyncShiftCount;
-		m_tvScreenData->setSampleValue(m_rowIndex,
-			shiftSamples < -1.0f ? -1.0f : (shiftSamples > 1.0f ? 1.0f : shiftSamples));
     }
 };
 
-
 #endif // INCLUDE_ATVDEMODSINK_H

sdrgui/gui/tvscreenanalog.cpp

@@ -104,10 +104,34 @@ void TVScreenAnalog::initializeGL()
 {
 	initializeOpenGLFunctions();
 
+	connect(QOpenGLContext::currentContext(), &QOpenGLContext::aboutToBeDestroyed,
+		this, &TVScreenAnalog::cleanup); // TODO: when migrating to QOpenGLWidget
+
 	m_shader = std::make_shared<QOpenGLShaderProgram>(this);
-	m_shader->addShaderFromSourceCode(QOpenGLShader::Fragment, fragmentShaderSource);
+	if (!m_shader->addShaderFromSourceCode(QOpenGLShader::Vertex, vertexShaderSource))
-	m_shader->addShaderFromSourceCode(QOpenGLShader::Vertex, vertexShaderSource);
+	{
-	m_shader->link();
+		qWarning()
+			<< "TVScreenAnalog::initializeGL: error in vertex shader:"
+			<< m_shader->log();
+		m_shader = nullptr;
+		return;
+	}
+	if (!m_shader->addShaderFromSourceCode(QOpenGLShader::Fragment, fragmentShaderSource))
+	{
+		qWarning()
+			<< "TVScreenAnalog::initializeGL: error in fragment shader:"
+			<< m_shader->log();
+		m_shader = nullptr;
+		return;
+	}
+	if (!m_shader->link())
+	{
+		qWarning()
+			<< "TVScreenAnalog::initializeGL: error linking shader:"
+			<< m_shader->log();
+		m_shader = nullptr;
+		return;
+	}
 
 	m_vertexAttribIndex = m_shader->attributeLocation("vertex");
 	m_texCoordAttribIndex = m_shader->attributeLocation("texCoord");
@@ -117,9 +141,6 @@ void TVScreenAnalog::initializeGL()
 	m_imageHeightLoc = m_shader->uniformLocation("imh");
 	m_texelWidthLoc = m_shader->uniformLocation("tlw");
 	m_texelHeightLoc = m_shader->uniformLocation("tlh");
-
-	connect(QOpenGLContext::currentContext(), &QOpenGLContext::aboutToBeDestroyed,
-		this, &TVScreenAnalog::cleanup); // TODO: when migrating to QOpenGLWidget
 }
 
 void TVScreenAnalog::initializeTextures()
@@ -162,6 +183,13 @@ void TVScreenAnalog::paintGL()
 {
 	m_isDataChanged = false;
 
+	if (!m_shader)
+	{
+		glClearColor(0.2f, 0.0f, 0.0f, 1.0f);
+		glClear(GL_COLOR_BUFFER_BIT);
+		return;
+	}
+
 	if (!m_imageTexture ||
 		m_imageTexture->width() != m_data->getWidth() ||
 		m_imageTexture->height() != m_data->getHeight())
@@ -192,7 +220,7 @@ void TVScreenAnalog::paintGL()
 	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
 		1, m_data->getHeight(), GL_RGBA, GL_UNSIGNED_BYTE, m_data->getLineShiftData());
 
-	float rectHalfWidth = 1.0f + 4 * texelWidth;
+	float rectHalfWidth = 1.0f + 4.0f / (imageWidth - 4.0f);
 	GLfloat vertices[] =
 	{
 		-rectHalfWidth, -1.0f,