[Ffmpeg-devel] problem with timestamps in a video file

[Vincent Torri]

Hello,

I'm using gstreamer to read a file (xvid stream, no audio, in a AVI) :

http://www.iecn.u-nancy.fr/~torri/files/gstreamer_test_seek/blood.avi

Gstreamer uses in that case ffmpeg. My aim is to do exact seeking (i work 
on avisynth 3.0). But it seems that the gstreamer plugin has problems with 
that file.

More precisely, when I seek to frame 0 (for example), the timestamp 
returned by gstreamer is 1.0/fps s., instead of 0 s.

One of the gstreamer dev analysed the file :

"[the file] has a decodable frame at time 0 but is delayed and 
outputted when the second frame is sent to the decoder. So the first frame 
to exit the decoder gets the timestamp of the second frame"

it seems that ffmpeg does not manage the timestamps for us, and it might 
buffer/delay/drop an unknown number of frames (it's only suppositions), 
and so, the guess of timestamps is quite complicated.

so, here is the question :

Is there a way to feed data+timestamp to the decoder and get a 
frame+corresponding timestamp back ?

thank you very much

Vincent Torri