typedef struct waveformat_tag {
    WORD    wFormatTag;        
    WORD    nChannels;         
    DWORD   nSamplesPerSec;    
    DWORD   nAvgBytesPerSec;   
    WORD    nBlockAlign;       
} WAVEFORMAT, *PWAVEFORMAT, NEAR *NPWAVEFORMAT, FAR *LPWAVEFORMAT;

typedef WAVEFORMAT NEAR *NPWAVEFORMAT;