Windows Media Video 9 Screen Decoder
The Windows Media Video 9 Screen decoder decodes streams that were encoded by the Windows Media Video 9 Screen Encoder.
The class identifier (CLSID) for the Windows Media Video 9 Screen decoder is represented by the constant CLSID_CMSSCDecMediaObject. You can create an instance of the decoder by calling CoCreateInstance.
The four-character code (FOURCC) for Windows Media Video Screen Version 9 encoded content is "MSS2".
The following input types are supported by the Version 9 Screen decoder.
The following output types are supported by the Version 9 Screen decoder when it is being used as a DirectX Media Object (DMO).
The following output types are supported by the Version 9 Screen decoder when it is being used as a Media Foundation Transform (MFT).
A screen 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).
A screen 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 screen decoder behaves as a DMO or an MFT.
|Operating system||Decoder behavior|
|Windows XP||A Windows Media Screen decoder always behaves as a DMO.|
|Windows Vista and Windows 7||By default, a Windows Media Screen decoder behaves as a DMO. If you obtain an IMFTransform interface on a screen decoder, it behaves as an MFT.|
You can use the same CLSID (CLSID_CMSSCDecMediaObject) to create the Version 7 Screen decoder and the Version 9 Screen decoder. The FOURCC for Windows Media Video Screen Version 7 encoded content is "MSS1". The Version 7 Screen decoder supports the MEDIASUBTYPE_MSS1 input type.
||Windows XP, Windows Vista or Windows 7