Talk:Microsoft MPEG-4

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erm, isnt some advanced profile wmv3 still not fully supported? --~

We don't qualify WMV3/VC-1 as being in the family of MS MPEG-4 codecs. The line ended with WMV2. --Multimedia Mike 23:23, 11 November 2007 (EST)
WMV3 != VC-1, WMV3 has own set of features, some of them unsupported (YUV411 interlacing, old P-frame coding scheme) and VC-1 has other things (slices, another form of interlacing). And WMV3 is definitely close to MSMPEG-4 than to anything else. --Kostya 00:03, 12 November 2007 (EST)
wmv3 is mpeg4, no? and its microsoft, so i thought microsoftmpeg4 was a good description. but ok.... --Compn 20:45, 12 November 2007 (EST)
VC-1 is H.264 AKA MPEG-4 AVC, but not really MPEG-4 ASP AFAIK. --DonDiego 05:02, 13 November 2007 (EST)
Um no it isn't. --Merbanan 05:45, 13 November 2007 (EST)
Isn't it based off some H.264 draft? --DonDiego 07:28, 13 November 2007 (EST)

Just for the sake of clarity. WMV3 is MSMPEG-4 evolved format, it even has the same tables. Also it uses the same macroblock structure and even old IDCT sometimes (along with some other WMV2 features). VC-1 is WMV3 cleared from some weird and unnecessary features with own advanced profile and features. While it uses 8x4, 4x8 and 4x4 transforms for some blocks (the main point in propaganda, but IIRC it was planned for WMV2 too) it has no relation to H.264 at all (which operates on 4x4 subblocks almost in any case). RealVideo 3/4 is H.264-based, Sorenson Video 3 is too. --Kostya 12:00, 13 November 2007 (EST)