[Ffmpeg-devel] lossless video codec comparison

[Kostya]

On Mon, Mar 19, 2007 at 01:11:26AM -0600, Loren Merritt wrote:
> On Sun, 18 Mar 2007, Mike Melanson wrote:
> >
> >The more interesting part about Lagarith is that it was designed for 
> >parallelization and the only version available is pre-optimized for MMX. 
> >This makes it difficult to RE a description for the Wiki:
> 
> The MMX parts are all identical to functions found in other codecs, so 
> that's no problem.
>
> I also don't see anything about the format that's especially "designed for 
> parallelization". Any intra-only format is embarrassingly parallel: just 
> run multiple codec instances on different frames.
> 
> imho the most interesting part is the arithcoder. Unlike 
> ffv1/snow/h264/vp*/jpeg2k which use binary arithcoders, lagarith stores a 
> whole coefficient in one symbol. End result is apparently that it's only 
> a few % slower than vlc.

Isn't that a normal operating mode for traditional arithmetic coding
(and range coding too)?
 
> --Loren Merritt
>