diff --git a/src/AvTranscoder/CodedStructures/CodedDesc.cpp b/src/AvTranscoder/CodedStructures/CodedDesc.cpp
index 1f132282..6e369f07 100644
--- a/src/AvTranscoder/CodedStructures/CodedDesc.cpp
+++ b/src/AvTranscoder/CodedStructures/CodedDesc.cpp
@@ -57,18 +57,18 @@ void CodedDesc::initCodecContext( )
 {
 	if( m_codec == NULL )
 	{
-		throw std::runtime_error( "unknown audio codec" );
+		throw std::runtime_error( "unknown codec" );
 	}
 
 	if( ( m_codecContext = avcodec_alloc_context3( m_codec ) ) == NULL )
 	{
-		throw std::runtime_error( "unable to create context for audio context" );
+		throw std::runtime_error( "unable to create context for context" );
 	}
 
 	// Set default codec parameters
 	if( avcodec_get_context_defaults3( m_codecContext, m_codec ) != 0 )
 	{
-		throw std::runtime_error( "unable to find audio codec default values" );
+		throw std::runtime_error( "unable to find codec default values" );
 	}
 }
 
diff --git a/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.cpp b/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.cpp
index 6e23bf3f..683c5ab1 100644
--- a/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.cpp
+++ b/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.cpp
@@ -34,6 +34,7 @@ VideoEssenceTransform::VideoEssenceTransform()
 	, _srcOffsets  ( MAX_SWS_PLANE, 0 )
 	, _dstOffsets  ( MAX_SWS_PLANE, 0 )
 	, _isInit      ( false )
+	, _verbose( false )
 {
 }
 
@@ -60,6 +61,34 @@ bool VideoEssenceTransform::init( const Frame& srcFrame, const Frame& dstFrame )
 	av_image_fill_linesizes( &_srcLineSize[0], src.desc().getPixelDesc().findPixel(), src.desc().getWidth() );
 	av_image_fill_linesizes( &_dstLineSize[0], dst.desc().getPixelDesc().findPixel(), dst.desc().getWidth() );
 
+	if( _verbose )
+	{
+		std::clog << "video conversion from ";
+		const char* pixFmt;
+		pixFmt = av_get_pix_fmt_name( src.desc().getPixelDesc().findPixel() );
+		std::clog << ( pixFmt != NULL ? pixFmt : "None" ) << " to ";
+		pixFmt = av_get_pix_fmt_name( dst.desc().getPixelDesc().findPixel() );
+		std::clog << ( pixFmt != NULL ? pixFmt : "None" ) << std::endl;
+
+		std::clog << "source, width = " << src.desc().getWidth() << std::endl;
+		std::clog << "source, height = " << src.desc().getHeight() << std::endl;
+		
+		std::clog << "source, lineSize:" << std::endl;
+		std::clog << "[0] = " << _srcLineSize[0] << std::endl;
+		std::clog << "[1] = " << _srcLineSize[1] << std::endl;
+		std::clog << "[2] = " << _srcLineSize[2] << std::endl;
+		std::clog << "[3] = " << _srcLineSize[3] << std::endl;
+		
+		std::clog << "destination, width = " << dst.desc().getWidth() << std::endl;
+		std::clog << "destination, height = " << dst.desc().getHeight() << std::endl;
+		
+		std::clog << "destination, lineSize:" << std::endl;
+		std::clog << "[0] = " << _dstLineSize[0] << std::endl;
+		std::clog << "[1] = " << _dstLineSize[1] << std::endl;
+		std::clog << "[2] = " << _dstLineSize[2] << std::endl;
+		std::clog << "[3] = " << _dstLineSize[3] << std::endl;
+	}
+
 	size_t cumulSrcOffset = 0;
 	size_t cumulDstOffset = 0;
 
@@ -108,6 +137,33 @@ void VideoEssenceTransform::convert( const Frame& srcFrame, Frame& dstFrame )
 		throw std::runtime_error( "unknown color convert context" );
 	}
 
+	if( _verbose )
+	{
+		std::clog << "source, offset:" << std::endl;
+		std::clog << "[0] = " << &_srcOffsets[0] << std::endl;
+		std::clog << "[1] = " << &_srcOffsets[1] << std::endl;
+		std::clog << "[2] = " << &_srcOffsets[2] << std::endl;
+		std::clog << "[3] = " << &_srcOffsets[3] << std::endl;
+		
+		std::clog << "source, slice:" << std::endl;
+		std::clog << "[0] = " << &_srcData[0] << std::endl;
+		std::clog << "[1] = " << &_srcData[1] << std::endl;
+		std::clog << "[2] = " << &_srcData[2] << std::endl;
+		std::clog << "[3] = " << &_srcData[3] << std::endl;
+		
+		std::clog << "destination, offset:" << std::endl;
+		std::clog << "[0] = " << &_dstOffsets[0] << std::endl;
+		std::clog << "[1] = " << &_dstOffsets[1] << std::endl;
+		std::clog << "[2] = " << &_dstOffsets[2] << std::endl;
+		std::clog << "[3] = " << &_dstOffsets[3] << std::endl;
+		
+		std::clog << "destination, slice:" << std::endl;
+		std::clog << "[0] = " << &_dstData[0] << std::endl;
+		std::clog << "[1] = " << &_dstData[1] << std::endl;
+		std::clog << "[2] = " << &_dstData[2] << std::endl;
+		std::clog << "[3] = " << &_dstData[3] << std::endl;
+	}
+
 	int ret = sws_scale( _imageConvertContext,
 		&_srcData[0], &_srcLineSize[0], 0, src.desc().getHeight(),
 		&_dstData[0], &_dstLineSize[0] );
diff --git a/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.hpp b/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.hpp
index d56ab161..08f00c85 100644
--- a/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.hpp
+++ b/src/AvTranscoder/EssenceTransform/VideoEssenceTransform.hpp
@@ -19,6 +19,8 @@ class AvExport VideoEssenceTransform : public EssenceTransform
 
 	void convert( const Frame& srcFrame, Frame& dstFrame );
 
+	void setVerbose( bool verbose = false ){ _verbose = verbose; }
+
 private:
 	bool init( const Frame& srcFrame, const Frame& dstFrame );
 
@@ -32,6 +34,8 @@ class AvExport VideoEssenceTransform : public EssenceTransform
 	std::vector<size_t>    _dstOffsets;
 
 	bool _isInit;
+
+	bool _verbose;
 };
 
 }