Capture Device Capabilities
[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 It has been superseded by WASAPI and Audio Graphs.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.]
To retrieve the capabilities of a capture device, call the IDirectSoundCapture8::GetCaps method. The parameter to this method is a pointer to a DSCCAPS structure. As with other such structures, you have to initialize the dwSize member before passing it. On return, the structure contains the number of channels the device supports, as well as a combination of values for supported formats, equivalent to the values in the WAVEINCAPS structure used in the Win32 waveform audio functions.
On non-WDM drivers, a capture device can be used by only one application at a time. If the driver supports simultaneous use of the device by more than one application, DSCCAPS_MULTIPLECAPTURE is returned in the dwFlags member of DSCCAPS. Each application can set its own format for the capture buffer.