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Re: Idle? We could need some help...



At 04:32 PM 17/02/2002 +0100, you wrote:
>Second, what about good, high-quality video codecs? I have so far found 
>none that is both high-quality and not bound to any patenting/licencing 
>issues that could make us pay (especially MPEG2/MPEG4, which we 
>therefore cannot use at all).

 I don't believe there are licensing issues with mpeg1/2 as there are
multiple free codecs available for these, however IANAL..

>I've attempted to develop an own codec, but as things turned out, 
>encoding is very slow (between 10 and 60s/frame on any of my machines) 
>and bandwidth usage is poor (about 1MB for 20 frames of animation at 
>640x480). However, it is lossless, meaning I can recover *every* frame 
>in its original form. The bottom line is that it's there, we can't use 
>it, but it still has some potential left. If anyone is interested I can 
>share the sources with you anytime you like.

 You could try mjpeg - http://mjpeg.sourceforge.net/
 There is also linuxvideo which is mpeg2 based at http://linuxvideo.org/
Or sampeg-2 at
http://rachmaninoff.informatik.uni-mannheim.de/sampeg/index.html

 If you still want lossless, you might want to look at Huffyuv, which is
GPL'd (but doesn't have a linux version, though since you've written your
own codec you may not have trouble porting it or at least using some of
it's concepts in your own code.)
http://www.math.berkeley.edu/%7Ebenrg/huffyuv.html
 btw, about 20:1 (what you claim, assuming 24bit) is pretty good for
lossless video. You'll probably have trouble improving on that without
moving to a lossy codec, though as with all compression it depends what
your original material is like as to what ratio you can achieve. (by "high
quality video codec" you could mean lossless or lossy, your message wasn't
very clear on that)
 Also you may want to ask about in news:comp.compression - I'm sure people
in there would be interested in the codec work you've done so far.

Regards, Errol