[MEncoder-users] Mencoder does not cut exactly

[TAJTHY Tamás]

Dear Etienne,

>> mencoder ..compression-arguments.. -ss 1.120 -endpos 1:23:00.000 -o
>> cut.avi patch.avi;
>>
>> My problem is that the resulted file does not contain the exact frames.
>> Depending on the -ss option it can be +/-1 frames different. At the end
>> position can be +/- 4 frames different. If I add 3-5 ms to the -ss and
>> -endpos options so the start become puntual, but the problem still
appears
>> at the end.

>The -ss and -endpos method is quite inacurrate (even if you got a very
> good accuracy for using those IMHO...).

> You'd better use -hr-edl-seek, after selecting good timestamps using
> -edlout. From the manpage: See
http://www.mplayerhq.hu/DOCS/HTML/en/edl.html for details.

I modified my program to generate edl file and I used -edl option in both
passes. The result is the same as with -ss and -endpos. I modified the start
and end times a little bit to cut the exact frames and it seems it is not
deterministic. If I add more lines to the edl file two frames appears at the
end of the first section. The first section does not start with the 1st
frame, but the 4th (and then goes the 1st and the other frames). I don't
uderstand why!

Could You thell me why mencoder can not cut an mjpeg file exactly?

Thanx in advance!