Windows Media MPEG-4 V3 Decoder

The Windows Media MPEG-4 V3 decoder decodes MPEG-4 V3 video streams.

Class Identifier

The class identifier (CLSID) for the Windows MPEG-4 V3 decoder is represented by the constant CLSID_CMpeg43DecMediaObject. You can create an instance of the MPEG-4 V3 decoder by calling CoCreateInstance.

Formats

The Windows Media MPEG-4 V3 decoder supports the following input media types.

• MEDIASUBTYPE_MP43
• MEDIASUBTYPE_mp43

The Windows Media MPEG-4 V3 decoder supports the following output media subtypes when it is acting as a DirectX Media Object (DMO).

• MEDIASUBTYPE_YUY2
• MEDIASUBTYPE_UYVY
• MEDIASUBTYPE_RGB32
• MEDIASUBTYPE_RGB24
• MEDIASUBTYPE_RGB565
• MEDIASUBTYPE_RGB8
• MEDIASUBTYPE_RGB555

The Windows Media MPEG-4 V3 decoder supports the following output media subtypes when it is acting as a Media Foundation Transform (MFT).

• MFVideoFormat_YUY2
• MFVideoFormat_UYVY
• MFVideoFormat_RGB32
• MFVideoFormat_RGB24
• MFVideoFormat_RGB565
• MFVideoFormat_RGB8
• MFVideoFormat_RGB555

Remarks

The Windows Media MPEG-4 V3 decoder object exposes the IMediaObject interface so that the object can be used as a DirectX Media Object (DMO), and it exposes the IMFTransform interface so that the object can be used as a Media Foundation Transform (MFT). The object has the same class identifier (CLSID) regardless of whether it acts as a DMO or an MFT.

The MPEG-4 V3 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 an MPEG-4 V3 decoder behaves as a DMO or an MFT.

The globally unique identifiers (GUIDs) for RGB media subtypes differ depending on whether a decoder is acting as a DMO or an MFT. The GUIDs for non-RGB media subtypes are the same, regardless of whether a decoder is acting as a DMO or an MFT. For information about the GUIDs that represent media subtypes, see Video Subtype GUIDs.

Requirements

See also

Codec Objects