typedef struct mpeg1waveformat_tag {
    WAVEFORMATEX    wfx;
    WORD            fwHeadLayer;
    DWORD           dwHeadBitrate;
    WORD            fwHeadMode;
    WORD            fwHeadModeExt;
    WORD            wHeadEmphasis;
    WORD            fwHeadFlags;
    DWORD           dwPTSLow;
    DWORD           dwPTSHigh;
} MPEG1WAVEFORMAT;

typedef MPEG1WAVEFORMAT                 *PMPEG1WAVEFORMAT;

typedef MPEG1WAVEFORMAT NEAR           *NPMPEG1WAVEFORMAT;

typedef MPEG1WAVEFORMAT FAR            *LPMPEG1WAVEFORMAT;