[Ffmpeg-devel] Help understanding AVParser

[Michael Niedermayer]

Hi

On Wed, Dec 20, 2006 at 12:01:24PM +0000, Cool_Zer0 wrote:
[...]
> >[...]
> >> I've tried other combinations like
> >> $ ffmpeg -i -vcodec h263 compressed.avi -vcodec mpeg1video tt.mpg
> >
> >this is of course meaningless nonsese what you want is
> >ffmpeg -f h263 -i compressed.avi ...
> 
> 
> 
> Now it works but with the same problems...
> I'm putting the file in attachment (it's only 121kb) for you to see.
> 
> >>From now on I'm totally stucked... I can't understand what the problem is 
> >>:(
> 
> At the end of this mail is the result of the ffmpeg conversion... It gives
> some errors... (May be that's the problem!!)...
> 
> 
> [...]
> >> But any have worked...
> >> :(
> >>
> >> We must be really dumb... I have three more people working in this
> >project
> >
> >yes, and to help others who have the same problem ... maybe you want to
> >suggest some improvements to the docs after you figured out where the
> >problem
> >was ...
> 
> 
> 
> It will be my pleasure. And it will help me improve my english :)
> 
> 
> also dont mix packets from unrelated streams like sending audio packets to
> >the video decoder and dont forget to parse and strip any RTP headers or
> >what
> >else non-h263 is there (iam just guessing, these could cause such errors)
> 
> 
> 
> Nop... I'm only saving H.263 packets... I even have use a hexadecimal
> display to show what I've saved and what I've received (with the help of
> Ethereal)...

i suggest you try:

ffmpeg -i somefileofyourchoice -f image2 -vcodec h263 -s 176x144 frame%d.h263

this will provide you with plenty of valid h263 frames for comparission


[...]
> [h263 @ 6899C000]slice end not reached but screenspace end (133 left 054A2A,
> score= -17)
> [h263 @ 6899C000]concealing 11 DC, 11 AC, 11 MV errors
> [h263 @ 6899C000]slice end not reached but screenspace end (128 left 7E07D1,
> score= -25)
> [h263 @ 6899C000]concealing 11 DC, 11 AC, 11 MV errors
> [h263 @ 6899C000]slice end not reached but screenspace end (128 left 7E07D1,
> score= -33)

this doesnt look like valid h263

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I do not agree with what you have to say, but I'll defend to the death your
right to say it. -- Voltaire