Share via

MFPKEY_WMAAECMA_DMO_SOURCE_MODE Property

  • Article
banner art

Specifies whether the Voice Capture DSP uses source mode or filter mode.

Constant for IPropertyBag

Available only by using IPropertyStore.

Data Type

VT_BOOL

Default Value

VARIANT_TRUE

Remarks

In source mode, the application does not need to send input data to the DSP, because the DSP automatically pulls data from the audio devices. In filter mode, the application must send the input data to the DSP.

This property can have the following values.

Value Description
VARIANT_FALSE Filter mode.
VARIANT_TRUE Source mode.

Note In source mode users should only call IMediaObject::SetOutputType to set output stream format, and do not call IMediaObject::SetInputType to set input stream formats. Otherwise DMO initialization will fail.

If the value of this property is VARIANT_TRUE, the DSP has zero inputs. If the value is VARIANT_FALSE, the DSP has one or two inputs, depending on the value of the MFPKEY_WMAAECMA_SYSTEM_MODE property, as shown in the following table.

Value of
MFPKEY_WMAAECMA_SYSTEM_MODE		 Number of inputs
OPTIBEAM_ARRAY_AND_AEC 2
OPTIBEAM_ARRAY_ONLY 1
SINGLE_CHANNEL_AEC 2
SINGLE_CHANNEL_NSAGC 1

Note   Only modes with a single input will work with the wrapper filter DMO from the DirectShow 9.0 API.

Applies To

Requirements

Client: Requires Windows Vista or Windows XP.

Header: Include wmcodecdsp.h.

See Also