[FFmpeg-user] Forcing ffmpeg to detect duration reliably

[Carl Eugen Hoyos]

tracey jaquith <tracey <at> archive.org> writes:

> I use this for our archives when I get an estimated duration 
> that seems wrong.  Much faster than the "ffmpeg -i
> input -f null -", though I'm sure there may be some pros/cons.
> 
> It uses "ffprobe" to "count video packets" and their durations, 
> finally printing a total #seconds.
> 
> ffprobe -select_streams v  -show_packets -print_format compact 
> *mpg  2>/dev/null | egrep -o
> 'duration_time=[^ ]+'|cut -f2 -d= | perl -ne 'chop; $n+=$_; 
> print (int($n*10)/10)."\n" if (eof());'
> 1800

Does this also work if the stream contains timestamp 
discontinuities?

Carl Eugen