[MPlayer-dev-eng] qclp Codec problems / information to developers

[Diego Biurrun]

On Wed, Oct 29, 2008 at 06:51:33PM +0100, Jean-Pierre Demailly wrote:
> 
> Many users still have problems with certain Quicktime files,
> especially those which involve the (Qualcomm) qclp audio codec.
> Mplayer does provides a binary audio codec "Quicktime.qts" which
> unfortunately is only available for 32 bit systems. In any
> case, the integration with mplayer (even in 32 bit) is not
> perfect. For instance, the Quicktime files from
>    http://www.anatomy.wisc.edu/courses/gross/DissectionXX.mov
> where XX=01...27
> will play with video and sound desynchronized.

What version of MPlayer are you using?  Does the desynchronization
appear with -demuxer lavf as well?

> It turns out that Qualcomm has actually provided a couple of years back
> a sample implementation of tools for their qclp codec. Here it is.
> I hope this might help for improving qclp support in
> libquicktime / mplayer.

This implementation is well-known to us, but it's nonfree unfortunately.

However, currently an LGPL implementation of QCELP is being reviewed on
ffmpeg-devel.  With a bit of luck, support for this audio codec should
be available as free software by the end of this year.

Also, please don't send such large attachments to mailing lists.

Diego