The waveOutSetPlaybackRate function sets the playback rate for the specified waveform-audio output device.
MMRESULT waveOutSetPlaybackRate( HWAVEOUT hwo, DWORD dwRate );
Handle to the waveform-audio output device.
New playback rate setting. This setting is a multiplier indicating the current change in playback rate from the original authored setting. The playback rate multiplier must be a positive value.
The rate is specified as a fixed-point value. The high-order word contains the signed integer part of the number, and the low-order word contains the fractional part. A value of 0x8000 in the low-order word represents one-half, and 0x4000 represents one-quarter. For example, the value 0x00010000 specifies a multiplier of 1.0 (no playback rate change), and a value of 0x000F8000 specifies a multiplier of 15.5.
Returns MMSYSERR_NOERROR if successful or an error otherwise. Possible error values include the following.
||Specified device handle is invalid.|
||No device driver is present.|
||Unable to allocate or lock memory.|
||Function isn't supported.|
Changing the playback rate does not change the sample rate but does change the playback time. Not all devices support playback rate changes. To determine whether a device supports playback rate changes, use the WAVECAPS_PLAYBACKRATE flag to test the dwSupport member of the WAVEOUTCAPS structure (filled by the waveOutGetDevCaps function).
|Minimum supported client||Windows 2000 Professional [desktop apps only]|
|Minimum supported server||Windows 2000 Server [desktop apps only]|
|Header||mmeapi.h (include Windows.h)|