audiodecoder.cpp

《Visual C++视频/音频开发实用工程案例精选》一书的源代码

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#include "AudioDecoder.h"



MediaAudioDecoder::MediaAudioDecoder()
{
	this->acmDecoder = new MediaAudioDecoderACM();
	this->mp3Decoder = new MediaAudioDecoderMP3();

	this->decoder    = NULL;
}

MediaAudioDecoder::~MediaAudioDecoder()
{
	delete this->acmDecoder;
	delete this->mp3Decoder;
}


media_type_t  MediaAudioDecoder::GetType()
{
	return MEDIA_TYPE_AUDIO_DECODER;
}

char         *MediaAudioDecoder::GetName()
{
	if(this->decoder)
		return this->decoder->GetName();

	return "Audio Decoder Wrapper";
}
	
MP_RESULT     MediaAudioDecoder::Connect(MediaItem *item)
{

	if(this->acmDecoder->Connect(item) == MP_RESULT_OK) {

		this->decoder = (MediaItemAudioDecoder *) this->acmDecoder;
		
		return MP_RESULT_OK;
	}

	if(this->mp3Decoder->Connect(item) == MP_RESULT_OK) {

		this->decoder = (MediaItemAudioDecoder *) this->mp3Decoder;
		
		return MP_RESULT_OK;
	}

	return MP_RESULT_ERROR;
}

MP_RESULT     MediaAudioDecoder::ReleaseConnections()
{
	if(this->decoder) {

		this->decoder->ReleaseConnections();
	}

	this->decoder = NULL;
	
	return MP_RESULT_OK;
}

DWORD         MediaAudioDecoder::GetCaps()
{
	return 0;
}

MP_RESULT     MediaAudioDecoder::Configure(HINSTANCE hInstance, HWND hwnd)
{
	return MP_RESULT_ERROR;
}



WAVEFORMATEX *MediaAudioDecoder::GetAudioFormat()
{
	if(this->decoder)
		return this->decoder->GetAudioFormat();

	return NULL;
}

MP_RESULT     MediaAudioDecoder::EmptyAudioBuffer()
{
	if(this->decoder)
		return this->decoder->EmptyAudioBuffer();

	return MP_RESULT_ERROR;
}

unsigned int  MediaAudioDecoder::Decompress(void *buffer, unsigned int size)
{
	if(this->decoder)
		return this->decoder->Decompress(buffer, size);

	return 0;
}