StreamTranscoder::StreamTranscoder(
		IInputStream& inputStream,
		IOutputFile& outputFile,
		const ProfileLoader::Profile& profile,
		const int subStreamIndex,
		const double offset
	)
	: _inputStream( &inputStream )
	, _outputStream( NULL )
	, _sourceBuffer( NULL )
	, _frameBuffer( NULL )
	, _inputDecoder( NULL )
	, _generator( NULL )
	, _currentDecoder( NULL )
	, _outputEncoder( NULL )
	, _transform( NULL )
	, _subStreamIndex( subStreamIndex )
	, _offset( offset )
	, _canSwitchToGenerator( false )
{
	// create a transcode case
	switch( _inputStream->getStreamType() )
	{
		case AVMEDIA_TYPE_VIDEO :
		{
			// input decoder
			VideoDecoder* inputVideo = new VideoDecoder( *static_cast<InputStream*>( _inputStream ) );
			// set decoder options with empty profile to set some key options to specific values (example: threads to auto)
			inputVideo->setProfile( ProfileLoader::Profile() );
			inputVideo->setup();
			_inputDecoder = inputVideo;
			_currentDecoder = _inputDecoder;

			// output encoder
			VideoEncoder* outputVideo = new VideoEncoder( profile.at( constants::avProfileCodec ) );
			_outputEncoder = outputVideo;

			VideoFrameDesc outputFrameDesc = _inputStream->getVideoCodec().getVideoFrameDesc();
			outputFrameDesc.setParameters( profile );
			outputVideo->setProfile( profile, outputFrameDesc );

			// output stream
			_outputStream = &outputFile.addVideoStream( outputVideo->getVideoCodec() );

			// buffers to process
			_sourceBuffer = new VideoFrame( _inputStream->getVideoCodec().getVideoFrameDesc() );
			_frameBuffer = new VideoFrame( outputVideo->getVideoCodec().getVideoFrameDesc() );

			// transform
			_transform = new VideoTransform();

			// generator decoder
			VideoGenerator* generatorVideo = new VideoGenerator();
			generatorVideo->setVideoFrameDesc( outputVideo->getVideoCodec().getVideoFrameDesc() );
			_generator = generatorVideo;

			break;
		}
		case AVMEDIA_TYPE_AUDIO :
		{
			// input decoder
			AudioDecoder* inputAudio = new AudioDecoder( *static_cast<InputStream*>( _inputStream ) );
			// set decoder options with empty profile to set some key options to specific values (example: threads to auto)
			inputAudio->setProfile( ProfileLoader::Profile() );
			inputAudio->setup();
			_inputDecoder = inputAudio;
			_currentDecoder = _inputDecoder;

			// output encoder
			AudioEncoder* outputAudio = new AudioEncoder( profile.at( constants::avProfileCodec )  );
			_outputEncoder = outputAudio;

			AudioFrameDesc outputFrameDesc( _inputStream->getAudioCodec().getAudioFrameDesc() );
			outputFrameDesc.setParameters( profile );
			if( subStreamIndex > -1 )
			{
				// @todo manage downmix ?
				outputFrameDesc.setChannels( 1 );
			}
			outputAudio->setProfile( profile, outputFrameDesc );

			// output stream
			_outputStream = &outputFile.addAudioStream( outputAudio->getAudioCodec() );

			// buffers to process
			AudioFrameDesc inputFrameDesc( _inputStream->getAudioCodec().getAudioFrameDesc() );
			if( subStreamIndex > -1 )
				inputFrameDesc.setChannels( 1 );

			_sourceBuffer = new AudioFrame( inputFrameDesc );
			_frameBuffer  = new AudioFrame( outputAudio->getAudioCodec().getAudioFrameDesc() );

			// transform
			_transform = new AudioTransform();

			// generator decoder
			AudioGenerator* generatorAudio = new AudioGenerator();
			generatorAudio->setAudioFrameDesc( outputAudio->getAudioCodec().getAudioFrameDesc() );
			_generator = generatorAudio;

			break;
		}
		default:
		{
			throw std::runtime_error( "unupported stream type" );
			break;
		}
	}
	if( offset )
		switchToGeneratorDecoder();
}