[MPlayer-users] edl accuracy in mplayer vs. mencoder

[pfile at pacbell.net]

On Dec 26, 2005, at 2:34 PM, Rich Felker <dalias at aerifal.cx> wrote:
>>
> On Mon, Dec 26, 2005 at 10:42:07AM -0800, pfile at pacbell.net wrote:
>> begins) happen a few seconds too late. changing the cutpoint to be
>> progressively earlier has no effect until finally mencoder starts
>> cutting in several seconds too early.
>
> You cannot do accurate editing with -ovc copy unless you use a codec
> where all frames are keyframes. Also I recommend using the
> -hr-edl-seek option with mencoder. And make sure your edl file has the
> exact timestamps you want to cut at, not whatever adjusted values work
> well for mplayer -edl (which is imprecise).
>
> Rich
>
>

so i guess it was just a coincidence then that i happened to have 
keyframes very near most of my computed cutpoints. (or maybe not -- 
perhaps the discontinuity in the video between content and commercial 
forces a keyframe to be generated.) oh well. strangely enough on at 
least two programs -edl was very accurate with mplayer so i took this 
to mean that there might be a bug in mencoder. the edl file should have 
exact timestamps since they were computed by mplayer itself, taken from 
sh_video->pts at the moment the commercials begin and end.

i think i will try to construct cutlists for avidemux then. in my 
limited experience with avidemux it appears to be able to cut at 
arbitrary frames. first i'll give -hr-edl-seek a shot and see what 
happens.

rob