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vceGetEncodingInfo
Description
- Gets information about a voice encoding.
Prototype
- DWORD vceGetEncodingInfo ( CTAHD ctahd,
unsigned encoding,
unsigned *framesize,
unsigned *frametime)
- ctahd Handle returned by ctaCreateContext.
- encoding The encoding ID, for example, VCE_ENCODE_NMS_24.
- framesize Pointer to the returned size (in bytes) of one frame. This can be NULL.
- frametime Pointer to the returned time (in milliseconds) represented by one frame. This can be NULL.
Return Values
Events
- None.
Details
- This function returns information about any encoding that is supported by the play/record service associated with the context (for example, the ADI service).
- framesize is the minimum data block size. Data at the specified encoding will always be a multiple of this size. frametime is the duration to play or record one frame. The data rate in bytes per second is framesize * 1000 / frametime.
- Use the following formulas to convert between milliseconds and bytes. Note that these translations truncate the results to frame multiples.
- Bytes = ( milliseconds / frametime ) * framesize
- Milliseconds = ( bytes / framesize ) * frametime
- Use vceGetOpenInfo to get the encoding used in an open voice object.
See Also
- vceGetOpenInfo
Example
/* Return message size in bytes */
unsigned myMsgSize (VCEHD vh, unsigned message)
{
VCE_OPEN_INFO openinfo;
unsigned framesize;
unsigned frametime;
unsigned msgsize;
vceGetOpenInfo (vh, &openinfo, sizeof openinfo) ;
vceGetEncodingInfo (openinfo.ctahd, openinfo.encoding, &framesize,
&frametime) ;
vceGetMessageSize (vh, message, &msgsize) ;
return (msgsize / frametime * framesize);
}
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