[MPlayer-users] Cut First Part of Movie

[The Wanderer]

n0dalus wrote:

> On 3/4/06, The Wanderer <inverseparadox at comcast.net> wrote:
> 
[a seek-to-frame option]
>> There are technical reasons why this has not been, and perhaps
>> cannot be, done (although I forget the details just at the moment).
>> If you think that it can be done regardless, then the onus is on
>> you to explain how or, preferably and more effectively, send a
>> patch.
> 
> I don't really know how hard it would be to write, but is there some
> way of making mplayer do accurate seeking by using null outputs? So,
> in this case it would jump in the video to the keyframe before the
> desired frame, then go through the normal process of "playing" the
> video and audio, as quickly as it can and without outputting any of
> it. Then when it gets to the right frame, it starts outputting.

Yes, this is in theory possible. I started trying to implement it once,
but got bogged down in A/V sync and actually getting the video decoding
done properly, and have not touched the effort in a long time.

If you can manage to implement it, send a patch. ^_^

However, that would not by itself be enough to implent a '-sf' option.
The problem is that in order to know which frame is the correct one, you
would have to count every preceding frame in the file, which would
involve parsing (if not actually decoding) every single one. This would
be ungodly slow if seeking to any location not *very* early in the file.

-- 
       The Wanderer

Warning: Simply because I argue an issue does not mean I agree with any
side of it.

Secrecy is the beginning of tyranny.