mpa_frame_header.h

来自「symbian 下的helix player源代码」· C头文件 代码 · 共 47 行

/*============================================================================*
 *
 * (c) 1995-2002 RealNetworks, Inc. Patents pending. All rights reserved.
 *
 *============================================================================*/
 
#ifndef MPA_FRAME_HEADER_H__
#define MPA_FRAME_HEADER_H__

#define MPA_FRAME_HDR_SZ 4	    // size of packed frame header
#define MPA_SAMPLES_PER_FRAME 1152  // all frames contain 1152 samples

#define MPA_VERSION1 3		// MPEG1 version is 11
#define MPA_VERSION2 2		// MPEG2 version is 10
#define MPA_VERSION_RESERVED 1	// Reserved version is 01
#define MPA_VERSION25 0		// MPEG2.5 version is 00
#define MPA_LAYER1 3 		// Layer I id is 11
#define MPA_LAYER2 2		// Layer II id is 10
#define MPA_LAYER3 1		// Layer III id is 01
#define MPA_LAYER_RESERVED 0	// Reserved Layer id is 00

class MPAFrameHeader 
{
public:
    int m_version;
    int m_layer;
    int m_hasCRC;
    int m_bitRate;
    int m_sampleRate;
    int m_pad;
    int m_chnlMode;
    int m_chnlModeEx;

    int m_frameSize;
    int m_samplesPerFrame;
    int m_channels;

    static bool IsSync(const unsigned char* p);
    bool Unpack(const unsigned char* p);
    //void DumpFrameInfo() const;

private:
    void ComputeFrameSize();
};

#endif // MPA_FRAME_HEADER_H__