Sorry, I will be more precise.
Michel Bardiaux <[EMAIL PROTECTED]> writes:
> >> What does ffmpeg -i say about your output file?
Original output file.
FFmpeg version SVN-r12661, Copyright (c) 2000-2008 Fabrice Bellard, et al.
configuration: --enable-memalign-hack --disable-shared --enable-static --
enable-pthreads --disable-stripping --prefix=/home/wl
libavutil version: 49.6.0
libavcodec version: 51.54.0
libavformat version: 52.13.0
libavdevice version: 52.0.0
built on Apr 2 2008 10:26:52, gcc: 4.2.1 (Ubuntu 4.2.1-5ubuntu4)
Input #0, mpeg, from 'p8211_2221_2231_2008-04-04-14-25-00_2008-04-04-14-35-
00.mpg':
Duration: 00:10:01.0, start: 84077.479689, bitrate: 3312 kb/s
Stream #0.0[0x1e0]: Video: mpeg2video, yuv420p, 720x576 [PAR 16:15 DAR
4:3], 3165 kb/s, 25.00 tb(r)
Stream #0.1[0x1c0]: Audio: mp2, 48000 Hz, mono, 64 kb/s
Then
$ ffmpeg -i p8211_2221_2231_2008-04-04-14-25-00_2008-04-04-14-35-00.mpg -acodec
copy -vcodec copy p8.mpg -f dvd
Then
$ ffmpeg -i p8.mpg
FFmpeg version SVN-r12661, Copyright (c) 2000-2008 Fabrice Bellard, et al.
configuration: --enable-memalign-hack --disable-shared --enable-static --
enable-pthreads --disable-stripping --prefix=/home/wl
libavutil version: 49.6.0
libavcodec version: 51.54.0
libavformat version: 52.13.0
libavdevice version: 52.0.0
built on Apr 2 2008 10:26:52, gcc: 4.2.1 (Ubuntu 4.2.1-5ubuntu4)
Input #0, mpeg, from 'p8.mpg':
Duration: 00:10:01.0, start: 0.500000, bitrate: 3237 kb/s
Stream #0.0[0x1c0]: Audio: mp2, 48000 Hz, mono, 64 kb/s
Stream #0.1[0x1e0]: Video: mpeg2video, yuv420p, 720x576 [PAR 16:15 DAR
4:3], 3165 kb/s, 25.00 tb(r)
> No, all wrong. Dont you notice you have mpeg2 in, but mpeg1 in the
> output? That's because you put the spec of p8.mpg after the file, it
> must be before.
Now all correct. :)
> > Sorry, one thing I forgot to mention.
> > When adding streams to the OutputFormatContext, I set
> > st->pts.num=st->time_base.num;
> > st->pts.den=st->time_base.den;
> > st is the result of av_new_stream( )
> >
> > I got divizion by 0 without setting pts, because compute_pkt_fileds2()
calls
> > avfrac_add, which tries to divide by pts.den, which is 0.
> >
> > And one more thing:
> >
> > static float mux_preload= 0.5;
> > static float mux_max_delay= 0.7;
> > output->preload= (int)(mux_preload*AV_TIME_BASE);
> > output->max_delay= (int)(mux_max_delay*AV_TIME_BASE);
> >
> > I was advised to do that here, mpeg muxer complains on buffer underflow
without
> > these assignments.
> >
> >
> >>> If the movie is recorded as MPEG PS and contains MPEG2 video and MPEG-1
> > audio,
> >>> how does a media player calculate its duration?
> >> There are several possible ways: subtract the first time stamp from the
> >> last; or, divide the file size by the nominal bit rate stated by the
> >> container (some containers like avi, store the duration explicitly;
> >> MPEG-PS doesn't though). IIRC ffmpeg uses the 2nd method.
> >
> > VLC and Kaffeine seem to use another method, or use some other fields in
the
> > file. I must set up them also.
> I cant comment on that if you are not more precise. *Which* other method?
That was only my supposition.
You have named two methods, and said that ffmpeg uses the second one, and
calculates the duration correctly. I just supposed that since vlc and kaffeine
don't calculate the movie duration correctly, they don't use that method, but
use some other.
I understand that this is a wrong list to ask questions about other media
players specifics.
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