acmFormatSuggest
The acmFormatSuggest
function queries the ACM or a specified ACM driver to suggest a destination
format for the supplied source format. For example, an application can use this
function to determine one or more valid PCM formats to which a compressed
format can be decompressed.
MMRESULT acmFormatSuggest(
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HACMDRIVER
had, |
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|
LPWAVEFORMATEX pwfxSrc, |
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LPWAVEFORMATEX pwfxDst, |
|
|
DWORD cbwfxDst, |
|
|
DWORD fdwSuggest |
|
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); |
|
Parameters
had
Handle of an
open instance of a driver to query for a suggested destination format. If this parameter
is NULL, the ACM attempts to find the best driver to suggest a destination
format.
pwfxSrc
Address of a WAVEFORMATEX structure that identifies
the source format for which a destination format will be suggested by the ACM
or specified driver.
pwfxDst
Address of a WAVEFORMATEX
structure that will receive the suggested destination format for the pwfxSrc
format. Depending on the fdwSuggest parameter, some members of the
structure pointed to by pwfxDst may require initialization.
cbwfxDst
Size, in
bytes, available for the destination format. The acmMetrics and acmFormatTagDetails functions can be used to
determine the maximum size required for any format available for the specified
driver (or for all installed ACM drivers).
fdwSuggest
Flags for
matching the desired destination format. The following values are defined:
ACM_FORMATSUGGESTF_NCHANNELS
The nChannels
member of the structure pointed to by pwfxDst is valid. The ACM will
query acceptable installed drivers that can suggest a destination format
matching nChannels or fail.
ACM_FORMATSUGGESTF_NSAMPLESPERSEC
The nSamplesPerSec
member of the structure pointed to by pwfxDst is valid. The ACM will
query acceptable installed drivers that can suggest a destination format
matching nSamplesPerSec or fail.
ACM_FORMATSUGGESTF_WBITSPERSAMPLE
The wBitsPerSample
member of the structure pointed to by pwfxDst is valid. The ACM will
query acceptable installed drivers that can suggest a destination format
matching wBitsPerSample or fail.
ACM_FORMATSUGGESTF_WFORMATTAG
The wFormatTag
member of the structure pointed to by pwfxDst is valid. The ACM will
query acceptable installed drivers that can suggest a destination format
matching wFormatTag or fail.
Return Values
Returns zero
if successful or an error otherwise. Possible error values include the following:
|
MMSYSERR_INVALFLAG |
At least
one flag is invalid. |
|
MMSYSERR_INVALHANDLE |
The
specified handle is invalid. |
|
MMSYSERR_INVALPARAM |
At least
one parameter is invalid. |
See Also