[FFmpeg-devel] About guess_correct_pts / AVFrame.best_effort_timestamp

[Nicolas George]

Hi.

Commit 76ad67c introduced best_effort_timestamp into AVFrame and moved
guess_correct_pts from cmdutils to lavc. It was accepted in ffmpeg at videolan
but not in ffmpeg at ffmpeg.

Keeping things concise, there are three issues here:

1. Do we want a single preferred timestamp for decoded frames, for
   applications that do not want to handle subtleties?

2. What API do we want for this timestamp?

3. What logic should be used to determine this timestamp?


My answers:

1. Definitely yes.
   The underlying timestamps should still be available for applications that
   want to handle subtleties.

2. A field in AVFrame, set at the same time as the rest of the structure.
   Exporting the underlying logic is ok, but only if there is a need for it.

3. The current algorithm seems fine to me for a start,
   but I do not insist on it if someone proposes something better.
   There have been hints of problems in the timestamp logic, but nothing
   precise that could be actually pinned on this algorithm.


I am willing to expand on any of these points, but I do not do it
immediately to avoid sidetracking.

Regards,

-- 
  Nicolas George
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20110216/6fe63d0e/attachment.pgp>