Michel Bardiaux <[EMAIL PROTECTED]> writes:
> What does ffmpeg -i say about your output file? Compared to what it says
> on the output file of ffmpeg -vcodec copy etc...?
Original recorded file:
$ ffmpeg -i p8211_2221_2231_2008-04-04-14-25-00_2008-04-04-14-35-00.mpg
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
Must supply at least one output file
Then
$ ffmpeg -i p8211_2221_2231_2008-04-04-14-25-00_2008-04-04-14-35-00.mpg p8.mpg -
f dvd -acodec copy -vcodec copy
$ ffmpeg -i p8.mpg
Input #0, mpeg, from 'p8.mpg':
Duration: 00:10:00.9, start: 0.500000, bitrate: 704 kb/s
Stream #0.0[0x1e0]: Video: mpeg1video, yuv420p, 720x576 [PAR 178:163 DAR
445:326], 104857 kb/s, 25.00 tb(r)
Stream #0.1[0x1c0]: Audio: mp2, 48000 Hz, mono, 64 kb/s
Must supply at least one output file
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.
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