[FFmpeg-devel] Westwood VQA3 demuxer additions

[Pekka Väänänen]

Greetings!

This small patch is required for high color 15-bit Westwood VQA3 videos
to be decoded properly. It just saves an offset of a VQFL chunk when it
sees one and then concatenates it with the packet of a later VQFR chunk
that contains full frame data. This way the (yet-to-be-merged) VQA3
decoder can apply the updated codebook before rendering a new frame and
each packet contains a standalone frame, as expected.

This change was already added by Adam Iglewski as part of GSoC 2009:

https://lists.ffmpeg.org/pipermail/ffmpeg-devel/2009-May/075047.html

However that patch had a memory leak with the dynamically allocated
memory:

https://lists.ffmpeg.org/pipermail/ffmpeg-devel/2009-May/075154.html

Here that problem is avoided because no heap allocation is done.

One question though: is it a problem that I use avio_seek() to rewind
the stream?