DSCFXAec Structure

[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 It has been superseded by WASAPI and Audio Graphs.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 DSCFXAec structure contains parameters for acoustic echo cancellation in a capture buffer.

Syntax

typedef struct DSCFXAec {
    BOOL fEnable;
    BOOL fNoiseFill;
    DWORD dwMode;
} DSCFXAec;

Members

• fEnable
  Boolean value that specifies whether the effect is enabled.
• fNoiseFill
  Boolean value that specifies whether to enable background comfort noise, which makes the capture signal sound more natural by preventing periods of dead silence. By default, background comfort noise is not enabled.
• dwMode
  Operation mode. This member contains one of the following values.

  Value	Description
  DSCFX_AEC_MODE_PASS_THROUGH	The effect is passing capture and render data through without modifying it.
  DSCFX_AEC_MODE_HALF_DUPLEX	The effect is running in half duplex mode. Not presently supported.
  DSCFX_AEC_MODE_FULL_DUPLEX	The effect is running in full duplex mode.

Remarks

The dwMode member is ignored when this structure is passed to IDirectSoundCaptureFXAec8::SetAllParameters.

Windows

Important Note for Windows Vista Existing applications that access Windows XP Acoustic Echo Cancellation (AEC) features via the DirectSound API will no longer obtain AEC when running on Windows Vista. These applications will still run, but their calls to AEC-specific DirectSound API calls will have no effect on the captured audio. To learn how to obtain AEC in Windows Vista, See the Windows Vista AEC topics in the Windows SDK.

Requirements

Header: Declared in DSound.h.

See Also

IDirectSoundCaptureFXAec8::GetAllParameters
IDirectSoundCaptureFXAec8::SetAllParameters