[MPlayer-users] frame-accurate playback/encoding

[D Richard Felker III]

On Sun, Oct 12, 2003 at 11:19:32PM +0200, Karl Ewald wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> Hi Rich,
> 
> stopping at any frame shouldn't be a problem at all as far as I understand
> things.
> Also I do not see any fundamental obstacle to starting to display/encode
> frames at non-keyframe boundaries, by seeking to the preceding keyframe and

You misunderstand. In many formats there is absolutely no way to know
the frame number of a frame without parsing the whole file from the
beginning. It has nothing to do with key/nonkey frames.

> decoding silently the intervening frames until the starting point is
> reached. This probably isn't worth it for viewing since waiting for the
> intended starting point without a picture or with some unrequested picture
> doesn't usually make a big difference, however when encoding it does.

I agree totally that there should be a higher-level seek function that
can seek to non-key frames by decoding from previous keyframe. I just
don't think using frame numbers is possible. Timestamps should be used
instead.

Rich