[FFmpeg-user] ffmpeg

[Stefano Sabatini]

On date Wednesday 2011-07-13 10:47:34 -0800, Lou encoded:
> On Tue, 12 Jul 2011 12:54:03 -0300
> "cmjury at gmail.com" <cmjury at gmail.com> wrote:
> 
> >  Hello I tried one of your tricks splitting my "zi6 quicktime mov" hd
> > videos, i have 250 clips of around 10 or 15 seconds each, from lot of
> > places, locationes around the globe and want to combine them in a
> > single big clip.
> 
> Are all of your inputs the same frame rate, format, etc?
> 
> > I can merge them very good with "mkvmerge".
> > The problem is that the first frames of all videos in the collection
> > (splitted with ffmpeg), are gray or with artifacts at beggining
> 
> With what player? Does it play as expected with ffplay?
> 
> > I do not know how to explain, maybe wrong ffmpeg commands, I'm
> > doing this (whit batch command line, which is great / fast for me):
> > 
> > =======begin of batch file
> > ffmpeg -i jockey_club_fpv.mov -ss 00:00:17 -t 00:00:24 -g 1 -sameq
> > -vcodec copy -vf fade=in:0:30 partes3a.mov
> 
> -g 1, -sameq, and -vf fade=in:0:30 options are not compatible with
> -vcodec copy. If you want to apply a fade in you will need to
> re-encode. I'm guessing that FFmpeg is using -vcodec copy and ignoring
> the other options.

I confirm (todo: issue a warning and/or exit since this it tricking
many people).
-- 
ffmpeg-user random tip #3
Some few multimedia formats (mpeg-1, mpeg-2:PS, DV) support physical merge 
consistency, which means you can merge two files with cat. E.g.:
cat input1.mpeg input2.mpeg > output.mpeg
See: http://www.ffmpeg.org/faq.html#SEC25