From 29b691a5af68c0fd060a257a7b9c09ba03bdded0 Mon Sep 17 00:00:00 2001
From: f4exb <f4exb06@gmail.com>
Date: Sun, 9 Apr 2017 17:43:23 +0200
Subject: [PATCH] ATV Demod: optimize scope feed

---
 plugins/channelrx/demodatv/atvdemod.cpp | 11 ++++++-----
 plugins/channelrx/demodatv/atvdemod.h   |  2 ++
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/plugins/channelrx/demodatv/atvdemod.cpp b/plugins/channelrx/demodatv/atvdemod.cpp
index aa5071527..48646fea7 100644
--- a/plugins/channelrx/demodatv/atvdemod.cpp
+++ b/plugins/channelrx/demodatv/atvdemod.cpp
@@ -221,10 +221,9 @@ void ATVDemod::feed(const SampleVector::const_iterator& begin, const SampleVecto
     if ((m_objRunning.m_intVideoTabIndex == 1) && (m_objScopeSink != 0)) // do only if scope tab is selected and scope is available
     {
         m_objScopeSink->feed(m_objScopeSampleBuffer.begin(), m_objScopeSampleBuffer.end(), false); // m_ssb = positive only
+        m_objScopeSampleBuffer.clear();
     }
 
-    m_objScopeSampleBuffer.clear();
-
     if (ptrBufferToRelease != 0)
     {
         delete ptrBufferToRelease;
@@ -404,10 +403,12 @@ void ATVDemod::demod(Complex& c)
         fltVal = 0.0f;
     }
 
-    fltVal = (fltVal < -1.0f) ? -1.0f : (fltVal > 1.0f) ? 1.0f : fltVal;
-    m_objScopeSampleBuffer.push_back(Sample(fltVal*32767.0f, 0.0f));
-
     fltVal = m_objRunning.m_blnInvertVideo ? 1.0f - fltVal : fltVal;
+    fltVal = (fltVal < -1.0f) ? -1.0f : (fltVal > 1.0f) ? 1.0f : fltVal;
+
+    if ((m_objRunning.m_intVideoTabIndex == 1) && (m_objScopeSink != 0)) { // feed scope buffer only if scope is present and visible
+        m_objScopeSampleBuffer.push_back(Sample(fltVal*32767.0f, 0.0f));
+    }
 
     m_fltAmpLineAverage += fltVal;
 
diff --git a/plugins/channelrx/demodatv/atvdemod.h b/plugins/channelrx/demodatv/atvdemod.h
index 512cbeb2c..15364661a 100644
--- a/plugins/channelrx/demodatv/atvdemod.h
+++ b/plugins/channelrx/demodatv/atvdemod.h
@@ -385,6 +385,8 @@ private:
     AvgExpInt m_objAvgColIndex;
     int m_intAvgColIndex;
 
+    SampleVector m_sampleBuffer;
+
     //*************** RF  ***************
 
     MovingAverage<double> m_objMagSqAverage;