Difference between revisions of "Cinepak"

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(corrected patch status)
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http://titan.codemill.se/~tomhar/cinepakenc.patch
 
http://titan.codemill.se/~tomhar/cinepakenc.patch
  
Unfortunately the open source encoder does not use all the possibilities of the format (f.i. skipped or partial codebook replacement). This is the probable reason why it does not achieve the performance of the proprietary one. It is also using the non-compliant YUV420 colorspace (should be easy to fix).
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Unfortunately both this open source encoder and the decoder present in ffmpeg are using the non-compliant YUV420 colorspace instead of the native Cinepak one (should be easy to fix).
  
The mentioned open source encoder was recently adapted for the current (December 2012) ffmpeg and slightly improved by Rl. This version is available at
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The mentioned open source encoder was recently adapted for the current (December 2012) ffmpeg and bugfixed by Rl. For a (not necessarily the latest) snapshot see
 
http://www.aetey.se/dl/cinepak-encoder-ffmpeg.patch
 
http://www.aetey.se/dl/cinepak-encoder-ffmpeg.patch
  

Revision as of 13:56, 8 February 2013

The Cinepak coding method is a vector quantization scheme with interframe update optimization. It is known to operate most commonly using a modified YUV 4:2:0 colorspace but also supports 256-grayscale mode. A modified variant of this format is used for full motion video on many Sega Saturn games (in Sega FILM files often bearing the .cpk extension). It is not known if this format has anything in common with the Cinepak For Sega format used in many Sega CD games.

ffmpeg contains an almost compliant decoder (using YUV420 instead of the Cinepak colorspace, which distorts colors somewhat - should be easy to fix).

There are several versions of a binary proprietary encoder/decoder as a windows dll, among others ftp://ftp.probo.com/pub/cinepak/cvid32.zip

There is also a simple and straightforward open source encoder as a ffmpeg patch, written in 2011 by Tomas Härdin and available at http://titan.codemill.se/~tomhar/cinepakenc.patch

Unfortunately both this open source encoder and the decoder present in ffmpeg are using the non-compliant YUV420 colorspace instead of the native Cinepak one (should be easy to fix).

The mentioned open source encoder was recently adapted for the current (December 2012) ffmpeg and bugfixed by Rl. For a (not necessarily the latest) snapshot see http://www.aetey.se/dl/cinepak-encoder-ffmpeg.patch

The encoder was never submitted for inclusion in ffmpeg, feel free to push it upstream.