[FFmpeg-devel] [PATCH] Enable PAFF decoding

[Uoti Urpala]

On Fri, 2007-10-12 at 12:05 +1000, Neil Brown wrote:
> On Friday October 12, michaelni at gmx.at wrote:
> > ive not looked at the stream at all, but from what you posted these b frames
> > have timestamps which lay prior to the first IDR picture if that is the case
> > the sane solution is to drop them
> 
> In my 11 second clip there are two IDR frames.  Each is followed (in
> decode order) by two B frames (pairs of B fields) which should be
> displayed (based on picture order count) before the IDR frame.
> (poc numbers for fields are, in decode order, 
>      0, 1, -4, -3, -2, -1, 4, 5, 2, 3, ...
>      I  P   B   B   B   B  P  P  B  B
> )
> 
> If we dropped all such frames, it would be sad - even if it would be sane.

Is this the start of the stream or not? Usually such B frames would
depend on earlier frames (before -4) and so would be dropped _if_
decoding starts from frame 0 here, but not if we get here after decoding
earlier parts and have frames buffered from there.