[Ffmpeg-devel] Frame rates and time_base

[Måns Rullgård]

Bill May <wmay at cisco.com> writes:

> M?ns Rullg?rd wrote:
>> OK, I'll try to rephrase it.  Where does libavcodec get the values it
>> puts in AVFrame.pts?  If the demuxer supplies a pts with a frame, I'd
>> like that pts to appear in the corresponding AVFrame.  How do I tell
>> libavcodec about the pts of the encoded frames I'm feeding it?
>
> I'd like to know if:
>
> for the encoder, if it is possible to put a DTS, then get the PTS
> of the returned frame ?  (x264 has this).
>
> for the decoder, pass in a PTS, and get a DTS from the decoded frame.

If PTS and DTS are different for an encoded frame, there is no way to
determine one from the other.  While decoding a sequence of frames, it
is of course possible to determine any PTS, given the PTS of one of
the frames.

While encoding, only PTS is meaningful as input, and the encoder may
reorder the output, resulting in different values for PTS and DTS of
the encoded frame.

-- 
M?ns Rullg?rd
mru at inprovide.com