IDirectSoundBuffer8::SetFrequency Method
[The feature associated with this page, DirectSound, is a legacy feature. It has been superseded by WASAPI and Audio Graphs. Media Casting have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Media Casting instead of DirectSound, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The SetFrequency method sets the frequency at which the audio samples are played.
Syntax
HRESULT SetFrequency(
DWORD dwFrequency
)
Parameters
- dwFrequency
Frequency, in hertz (Hz), at which to play the audio samples. A value of DSBFREQUENCY_ORIGINAL resets the frequency to the default value of the buffer format.
Return Value
If the method succeeds, the return value is DS_OK. If the method fails, the return value may be one of the following error values:
| Return code |
| DSERR_CONTROLUNAVAIL |
| DSERR_GENERIC |
| DSERR_INVALIDPARAM |
| DSERR_PRIOLEVELNEEDED |
Remarks
Increasing or decreasing the frequency changes the perceived pitch of the audio data. This method does not affect the format of the buffer.
Before setting the frequency, you should ascertain whether the frequency is supported by checking the dwMinSecondarySampleRate and dwMaxSecondarySampleRate members of the DSCAPS structure for the device. Some operating systems do not support frequencies greater than 100,000 Hz.
This method is not valid for the primary buffer.
Requirements
Header: Declared in DSound.h.
Library: Use Dsound3d.dll.