[FFmpeg-devel] [PATCH] Implement guessed_pts in avcodec_decode_video2.

[Måns Rullgård]

Alexander Strange <astrange at ithinksw.com> writes:

> On Jan 30, 2011, at 2:28 PM, Nicolas George wrote:
>
>> 
>> Signed-off-by: Nicolas George <nicolas.george at normalesup.org>
>> ---
>> cmdutils.c           |   27 ---------------------------
>> cmdutils.h           |   24 ------------------------
>> ffmpeg.c             |   14 ++++++--------
>> ffplay.c             |   10 +++-------
>> libavcodec/avcodec.h |   20 ++++++++++++++++++++
>> libavcodec/utils.c   |   43 ++++++++++++++++++++++++++++++++++++++++++-
>> 6 files changed, 71 insertions(+), 67 deletions(-)
>> 
>> This patch moves the guess_correct_pts function from cmdutils to libavcodec.
>> The feature is available through a new field in AVFrame, guessed_pts.
>> 
>> make test and ffplay still work, but I would like to have some more time to
>> read it carefully, but I have things to do in the next few days, and this
>> feature was discussed in another thread, so here the current version. It
>> will conflict with some patches that will certainly soon be applied, so I
>> will update and submit it again anyway.
>> 
>> Regards,
>> 
>> -- 
>>  Nicolas George
>> 
>> [..]
>> +\
>> +    /**\
>> +     * pts estimated using various heuristics, in stream time base\
>> +     * - encoding: unused\
>> +     * - decoding: set by libavcodec, read by user.\
>> +     */\
>> +    int64_t guessed_pts;\
>
> It's not quite estimated, it's chosen from either pts or dts.  I
> think the name should be reassuring - though I can't think of one,
> just 'timestamp'?
> Also, the comment should say that clients can rely on this as the
> time of the frame.

But can they?  The current code certainly doesn't look reliable to me.

-- 
M?ns Rullg?rd
mans at mansr.com