acmDriverEnumCallback

The acmDriverEnumCallback function specifies a callback function used with the acmDriverEnum function. The acmDriverEnumCallback name is a placeholder for an application-defined function name.

BOOL ACMDRIVERENUMCB acmDriverEnumCallback(
  HACMDRIVERID hadid,  
  DWORD dwInstance,    
  DWORD fdwSupport     
);
 

Parameters

hadid

Handle of an ACM driver identifier.

dwInstance

Application-defined value specified in acmDriverEnum.

fdwSupport

Driver-support flags specific to the driver specified by hadid. These flags are identical to the fdwSupport flags of the ACMDRIVERDETAILS structure. This parameter can be a combination of the following values:

ACMDRIVERDETAILS_SUPPORTF_ASYNC

Driver supports asynchronous conversions.

ACMDRIVERDETAILS_SUPPORTF_CODEC

Driver supports conversion between two different format tags. For example, if a driver supports compression from WAVE_FORMAT_PCM to WAVE_FORMAT_ADPCM, this flag is set.

ACMDRIVERDETAILS_SUPPORTF_CONVERTER

Driver supports conversion between two different formats of the same format tag. For example, if a driver supports resampling of WAVE_FORMAT_PCM, this flag is set.

ACMDRIVERDETAILS_SUPPORTF_DISABLED

Driver has been disabled. An application must specify the ACM_DRIVERENUMF_DISABLED flag with acmDriverEnum to include disabled drivers in the enumeration.

ACMDRIVERDETAILS_SUPPORTF_FILTER

Driver supports a filter (modification of the data without changing any of the format attributes). For example, if a driver supports volume or echo operations on WAVE_FORMAT_PCM, this flag is set.

Return Values

The callback function must return TRUE to continue enumeration or FALSE to stop enumeration.

Remarks

The acmDriverEnum function will return MMSYSERR_NOERROR (zero) if no ACM drivers are installed. Moreover, the callback function will not be called.

The following functions should not be called from within the callback function: acmDriverAdd, acmDriverRemove, and acmDriverPriority.

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in msacm.h.
  Import Library: User-defined.

See Also

Audio Compression Manager Overview, Audio Compression Functions, ACMDRIVERDETAILS, acmDriverEnum, acmDriverAdd, acmDriverRemove, and acmDriverPriority