Microsoft Screen Codec
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Also known as Windows Media Screen Codec.
- FourCCs: MSS1, MSS2, MSA1
- Samples:
MSA1 is created by Live Meeting 2007
Some details about format
Both MSS1 and MSS2 are quite close (thus are decoded with single decoder). They employ arithmetic coding - real one, with probability coding. This coding is used with several adaptive models, which look a bit like PPM.
Extradata format
(for some reason, data in .wmv is stored in big-endian order)
4- 7 header length 8-11 major version 12-15 minor version 16-19 display width 20-23 display height 24-27 coded width 28-31 coded height 32-35 frames per second (float) 36-39 bitrate 40-43 max lead time (float) 44-47 max lag time 48-51 max seek time 52-55 nFreeColors 56-... palette (256 RGB triplets)