diff --git a/source/InputStream.cpp b/source/InputStream.cpp
index 7ae34bc..4583124 100755
--- a/source/InputStream.cpp
+++ b/source/InputStream.cpp
@@ -212,7 +212,7 @@ Void InputStream::readFrame()
   }
 
   m_iCurrFrameNum++;
-  if( m_iCurrFrameNum >= m_uiTotalFrameNum )
+  if( m_iCurrFrameNum >= (Int)m_uiTotalFrameNum )
   {
     m_iErrorStatus = END_OF_SEQ;
     m_iCurrFrameNum = 0;
@@ -249,8 +249,6 @@ Bool InputStream::writeFrame( const QString& filename )
 
 PlaYUVerFrame* InputStream::getFrame( PlaYUVerFrame *pyuv_image )
 {
-  Pel*** bufferRGB = m_cCurrFrame->getPelBufferRGB();
-
   if( pyuv_image == NULL )
     pyuv_image = new PlaYUVerFrame( m_cCurrFrame->getWidth(), m_cCurrFrame->getHeight(), m_cCurrFrame->getPelFormat() );
 
diff --git a/source/ModulesHandle.cpp b/source/ModulesHandle.cpp
index c743fae..45781a8 100644
--- a/source/ModulesHandle.cpp
+++ b/source/ModulesHandle.cpp
@@ -74,8 +74,6 @@ QMenu* ModulesHandle::createMenus( QMenuBar *MainAppMenuBar )
   PlaYUVerModuleIf* currModuleIf;
   QAction* currAction;
   QMenu* currSubMenu;
-  Bool bCategoryExists;
-  Int iNumberCategories = 0;
 
   m_pcActionMapper = new QSignalMapper( this );
   connect( m_pcActionMapper, SIGNAL( mapped(int) ), this, SLOT( selectModule(int) ) );
diff --git a/source/PlaYUVerFrame.cpp b/source/PlaYUVerFrame.cpp
index fc9e679..53b0940 100755
--- a/source/PlaYUVerFrame.cpp
+++ b/source/PlaYUVerFrame.cpp
@@ -109,9 +109,9 @@ static inline void yuvToRgb( int iY, int iU, int iV, int &iR, int &iG, int &iB )
 Void PlaYUVerFrame::YUV420toRGB()
 {
   Int iY, iU, iV, iR, iG, iB;
-  for( Int y = 0; y < m_uiHeight; y += 2 )
+  for( UInt y = 0; y < m_uiHeight; y += 2 )
   {
-    for( Int x = 0; x < m_uiWidth; x += 2 )
+    for( UInt x = 0; x < m_uiWidth; x += 2 )
     {
       // Pixel (x, y).
 
@@ -216,9 +216,9 @@ QImage PlaYUVerFrame::getQimage()
 
   if( sizeof(Pel) == sizeof(unsigned char) )
   {
-    for( Int y = 0; y < m_uiHeight; y++ )
+    for( UInt y = 0; y < m_uiHeight; y++ )
     {
-      for( Int x = 0; x < m_uiWidth; x++ )
+      for( UInt x = 0; x < m_uiWidth; x++ )
       {
         img.setPixel( x, y, qRgb( bufferRGB[0][y][x], bufferRGB[1][y][x], bufferRGB[2][y][x] ) );
       }
diff --git a/source/PlaYUVerModuleIf.h b/source/PlaYUVerModuleIf.h
index 5f2fe6f..257c6b2 100644
--- a/source/PlaYUVerModuleIf.h
+++ b/source/PlaYUVerModuleIf.h
@@ -47,9 +47,9 @@ enum __PlaYUVerModuleTypes
 typedef struct __PlaYUVerModuleDefinition
 {
   int   m_pchModuleType;
-  char* m_pchModuleCategory;
-  char* m_pchModuleName;
-  char* m_pchModuleTooltip;
+  const char* m_pchModuleCategory;
+  const char* m_pchModuleName;
+  const char* m_pchModuleTooltip;
 }PlaYUVerModuleDefinition;
 
 
@@ -72,7 +72,7 @@ public:
   virtual Void process() {};
 
   virtual Void create( PlaYUVerFrame* ) {};
-  virtual PlaYUVerFrame* process( PlaYUVerFrame* ) {};
+  virtual PlaYUVerFrame* process( PlaYUVerFrame* ) { return NULL; };
 
   virtual Void destroy() {};
 
diff --git a/source/SubWindowHandle.cpp b/source/SubWindowHandle.cpp
index d470925..bfc07e0 100644
--- a/source/SubWindowHandle.cpp
+++ b/source/SubWindowHandle.cpp
@@ -146,9 +146,9 @@ QImage* SubWindowHandle::FrameToQImage( PlaYUVerFrame* curr_frame )
 
   curr_frame->YUV420toRGB();
 
-  for( Int y = 0; y < curr_frame->getHeight(); y++ )
+  for( UInt y = 0; y < curr_frame->getHeight(); y++ )
   {
-    for( Int x = 0; x < curr_frame->getWidth(); x++ )
+    for( UInt x = 0; x < curr_frame->getWidth(); x++ )
     {
       m_pCurrFrameQImage->setPixel( x, y, qRgb( bufferRGB[0][y][x], bufferRGB[1][y][x], bufferRGB[2][y][x] ) );
     }
@@ -245,7 +245,7 @@ Void SubWindowHandle::zoomToFit()
 {
   // Scale to a smaller size that the real to a nicer look
   QSize niceFit( m_cScrollArea->viewport()->size().width() - 10, m_cScrollArea->viewport()->size().height() - 10 );
-  if( m_pCurrStream->getWidth() <= niceFit.width() && m_pCurrStream->getHeight() <= niceFit.height() )
+  if( (Int)m_pCurrStream->getWidth() <= niceFit.width() && (Int)m_pCurrStream->getHeight() <= niceFit.height() )
   {
     normalSize();
     return;
diff --git a/source/modules/FilterFrame.cpp b/source/modules/FilterFrame.cpp
index 7476a6d..4bbc853 100644
--- a/source/modules/FilterFrame.cpp
+++ b/source/modules/FilterFrame.cpp
@@ -56,9 +56,9 @@ PlaYUVerFrame* FilterFrame::process( PlaYUVerFrame* InputFrame )
 
   m_pcFilteredFrame->CopyFrom( InputFrame );
 
-  for( Int y = 0; y < m_pcFilteredFrame->getHeight() / 2; y++ )
+  for( UInt y = 0; y < m_pcFilteredFrame->getHeight() / 2; y++ )
   {
-    for( Int x = 0; x < m_pcFilteredFrame->getWidth() / 2; x++ )
+    for( UInt x = 0; x < m_pcFilteredFrame->getWidth() / 2; x++ )
     {
       pppPelYUV[1][y][x] = 128;
       pppPelYUV[2][y][x] = 128;