ACMDRVSTREAMSIZE

typedef struct {
    DWORD cbStruct;      
    DWORD fdwSize;       
    DWORD cbSrcLength;   
    DWORD cbDstLength;   
} ACMDRVSTREAMSIZE;
 

Contains information needed by an Audio Compression Manager (ACM) driver to respond to the ACMDM_STREAM_SIZE message. The lParam2 parameter of the acmDriverProc function will contain a pointer to this structure during the ACMDM_STREAM_SIZE message.

Members

cbStruct

Size, in bytes, of the ACMDRVSTREAMSIZE structure. This member will be initialized by the ACM before calling the driver. This member can be greater than the size, in bytes, of the base ACMDRVSTREAMSIZE structure. An ACM driver should ignore any members that are not contained in the base ACMDRVSTREAMSIZE structure. This member should not be modified by the driver.

fdwSize

Flags for the stream-size query. This member should not be modified by the driver.

ACM_STREAMSIZEF_DESTINATION	Indicates that the cbDstLength member contains the size of the application's destination buffer in bytes. The driver should return the recommended source buffer size, in bytes, in the cbSrcLength member. A driver should not modify the cbDstLength member if this query type is specified.
ACM_STREAMSIZEF_SOURCE	Indicates that the cbSrcLength member contains the size of the application's source buffer in bytes. The driver should return the recommended destination buffer size, in bytes, in the cbDstLength member. A driver should not modify the cbSrcLength member if this query type is specified.

cbSrcLength

Size, in bytes, of the source buffer. This member is an input parameter if the query type specified in the fdwSize member is ACM_STREAMSIZEF_SOURCE. This member is an output parameter if the query type specified in the fdwSize member is ACM_STREAMSIZEF_DESTINATION.

cbDstLength

Size, in bytes, of the destination buffer. This member is an input parameter if the query type specified in the fdwSize member is ACM_STREAMSIZEF_DESTINATION. This member is an output parameter if the query type specified in the fdwSize member is ACM_STREAMSIZEF_SOURCE.

See Also

ACMDM_STREAM_CLOSE, ACMDM_STREAM_CONVERT, ACMDM_STREAM_OPEN, ACMDM_STREAM_PREPARE, ACMDM_STREAM_RESET, ACMDM_STREAM_SIZE, ACMDM_STREAM_UNPREPARE, ACMDRVOPENDESC, ACMDRVSTREAMHEADER, ACMDRVSTREAMINSTANCE