ACMDM_FORMAT_SUGGEST
lParam1 = (LPARAM) pacmDFS // see below
lParam2 = reserved // should be ignored
Sent to an Audio Compression Manager (ACM) driver to suggest a destination format for a given source format for a conversion. This message is usually sent to an ACM driver in response to an acmFormatSuggest call.
- Return MMSYSERR_NOERROR if the operation is successful or an error value otherwise. The following errors are possible:
| ACMERR_NOTPOSSIBLE |
The ACMDRVFORMATSUGGEST structure and suggestion restrictions specify information that cannot be satisfied by the driver. |
| MMSYSERR_NOTENABLED |
The driver failed to load or initialize. |
| MMSYSERR_NOTSUPPORTED |
The driver does not support format suggestion operations. |
- lParam1
- Address of the ACMDRVFORMATSUGGEST structure that defines how a destination format should be suggested, given a particular source format.
An ACM driver must support this message if it supports the ACMDM_STREAM_OPEN message and conversions other than filtering operations are available. Note that the following parameters for the ACMDM_FORMAT_SUGGEST message will be validated before calling the driver:
- The lParam1 parameter will contain a valid pointer to an ACMDRVFORMATSUGGEST structure with all members initialized. This structure will be at least the size of the base ACMDRVFORMATSUGGEST structure.
- The cbStruct member of the ACMDRVFORMATSUGGEST structure will be set to at least the size, in bytes, of the base ACMDRVFORMATSUGGEST structure.
- The pwfxSrc member of the ACMDRVFORMATSUGGEST structure will be a valid pointer to a WAVEFORMATEX structure that is at least the size, in bytes, specified in the cbwfxSrc member of the ACMDRVFORMATSUGGEST structure.
- The pwfxDst member of the ACMDRVFORMATSUGGEST structure will be a valid pointer to a WAVEFORMATEX structure that is at least the size, in bytes, specified in the cbwfxDst member of the ACMDRVFORMATSUGGEST structure.
- No invalid flag combinations will be specified in lParam2.
The driver need not check for these conditions.
See Also
ACMDM_FORMAT_DETAILS, ACMDM_FORMATTAG_DETAILS, ACMDRVFORMATSUGGEST