Windows Media Video 9 Advanced Profile Codec

The Windows Media Video 9 Advanced Profile encoder object is instantiated using the same class identifier as the Windows Media Video 9 encoder: CLSID_CWMV9EncMediaObject. The decoder object is instantiated using the class identifier CLSID_CWMVDecMediaObject. The FOURCC for Windows Media Video 9 Advanced Profile encoded content is "WVC1".

Encoder Properties

The following properties, in addition to the properties of Windows Media Video 9 encoder, can be set on the Windows Media Video 9 Advanced Profile encoder.

Property Description
MFPKEY_DELTAMVRANGEINDEX Specifies the method used to encode the motion vector information.
MFPKEY_FORCEFRAMEHEIGHT Specifies an intermediate frame height for encoded video.
MFPKEY_FORCEFRAMEWIDTH Specifies an intermediate frame width for encoded video.
MFPKEY_INTERLACEDCODINGENABLED Specifies whether interlaced video encoding will be used.
MFPKEY_RANGEREDUX Specifies the degree to which the codec should reduce the effective color range of the video.
MFPKEY_VTYPE Specifies the logic that the codec will use to detect interlaced source video.

Remarks

A video encoder or decoder object exposes the IMediaObject interface so that the object can be used as a DirectX Media Object (DMO), and the IMFTransform interface so that the object can be used as a Media Foundation Transform (MFT).

A video encoder or decoder behaves as a DMO or an MFT depending on which interfaces you obtain and which version of Windows is running. The following table shows the conditions under which a video encoder or decoder behaves as a DMO or an MFT.

Operating system Encoder or decoder behavior
Windows XP A Windows Media video encoder or decoder always behaves as a DMO.
Windows Vista and Windows 7 By default, a Windows Media video encoder or decoder behaves as a DMO. If you obtain an IMFTransform interface on a video encoder or decoder, it behaves as an MFT.

Beginning with Windows 7, the Windows Media Video Advanced Profile Decoder implements the IDMOQualityControl interface. For information about the IDMOQualityControl interface, see the DirectX Media Objects section of the DirectShow SDK documentation.

Requirements

Client Requires Windows XP, Windows Vista, or Windows 7.
Header Declared in Wmcodecdsp.h.
Library Use Wmvencod.dll for the encoder or wmvdecod.dll for the decoder.

See Also

Codec Objects
Using the Windows Media Video 9 Advanced Profile Codec

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Build date: 1/27/2009