diff --git a/source/app/PlaYUVerModuleIf.h b/source/app/PlaYUVerModuleIf.h
index 175d085..5e6b475 100644
--- a/source/app/PlaYUVerModuleIf.h
+++ b/source/app/PlaYUVerModuleIf.h
@@ -45,6 +45,7 @@ enum __PlaYUVerModuleTypes
   VIDEO_LEVEL_MODULE,
 };
 
+#define APPLY_WHILE_PLAYING true
 #define MAX_NUMBER_FRAMES 3
 
 enum __PlaYUVerModuleRequirements
@@ -75,6 +76,7 @@ typedef struct __PlaYUVerModuleDefinition
   const Char* m_pchModuleTooltip;
   UInt m_uiNumberOfFrames;
   UInt m_uiModuleRequirements;
+  Bool m_bApplyWhilePlaying;
 } PlaYUVerModuleDefinition;
 
 class SubWindowHandle;
diff --git a/source/modules/DisparityCVVar.cpp b/source/modules/DisparityCVVar.cpp
index cb062e6..ffd2115 100644
--- a/source/modules/DisparityCVVar.cpp
+++ b/source/modules/DisparityCVVar.cpp
@@ -37,7 +37,9 @@ static PlaYUVerModuleDefinition DisparityCVVarDef =
     "StereoVar",
     "Measure the disparity between two images using the Stereo Var method (OpenCV)",
     MODULE_REQUIRES_TWO_FRAMES,
-    MODULE_REQUIRES_NEW_WINDOW, };
+    MODULE_REQUIRES_NEW_WINDOW,
+    !APPLY_WHILE_PLAYING,
+};
 
 DisparityCVVar::DisparityCVVar()
 {
diff --git a/source/modules/FilterFrame.cpp b/source/modules/FilterFrame.cpp
index 16a6d80..32edadb 100644
--- a/source/modules/FilterFrame.cpp
+++ b/source/modules/FilterFrame.cpp
@@ -37,6 +37,7 @@ PlaYUVerModuleDefinition FilterFrameDef = {
     "Filter Y matrix of YUV frame",
     MODULE_REQUIRES_ONE_FRAME,
     MODULE_REQUIRES_NOTHING,
+    APPLY_WHILE_PLAYING,
 };
 
 FilterFrame::FilterFrame()
diff --git a/source/modules/FrameDifference.cpp b/source/modules/FrameDifference.cpp
index 3b7b1c4..1be0f20 100644
--- a/source/modules/FrameDifference.cpp
+++ b/source/modules/FrameDifference.cpp
@@ -38,6 +38,7 @@ static PlaYUVerModuleDefinition FrameDifferenceDef =
     "Measure the difference between two images (Y plane)",
     MODULE_REQUIRES_TWO_FRAMES,
     MODULE_REQUIRES_NEW_WINDOW,
+    APPLY_WHILE_PLAYING,
 };
 
 FrameDifference::FrameDifference()
diff --git a/source/modules/MeasurePSNR.cpp b/source/modules/MeasurePSNR.cpp
index d60ffc6..50b3357 100644
--- a/source/modules/MeasurePSNR.cpp
+++ b/source/modules/MeasurePSNR.cpp
@@ -38,6 +38,7 @@ static PlaYUVerModuleDefinition MeasurePSNRDef =
     "Measure the PSNR between two images",
     MODULE_REQUIRES_TWO_FRAMES,
     MODULE_REQUIRES_NEW_WINDOW,
+    APPLY_WHILE_PLAYING,
 };
 
 MeasurePSNR::MeasurePSNR()