[FFmpeg-devel] [patch] mjpeg restart marker parsing

[Tom Harper]

in the mjpeg code the parsing code is not checking to see if the proper 
next restart marker is present at the assumed restart marker boundary- 
if there are stuffing bits for example present instead of the marker the 
following error is often seen:
[mjpeg @ 6B0445C4]
sequencial DCT  p:0 >>:0 ilv:63 bits:8
[mjpeg @ 6B0445C4]
mjpeg_decode_dc: bad vlc: 0:0 (01BBDAA0)

so this error causes the decoder to bail out, resulting in the picture 
not being fully decoded.  The restart markers are supposed to provide 
recovery points but that is another patch for another day.

In any case I fixed the basic case, which is to look for the actual 
restart marker at or near where the next marker is supposed to be.  So 
that is the purpose of this patch.

Feedback appreciated, I think particularly for mjpeg web cameras this is 
a helpful patch.

Tom
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