[MEncoder-users] Detecting black areas in video

[Evgeniy Stepanov]

On Thursday 24 August 2006 18:49, Jean Hoderd wrote:
> I need to locate areas in video where the image goes completely black
> for a couple of seconds.  I have looked into mplayer's filters, but
> couldn't find nothing that helps (at least at first sight).
>
> I have thought of using "-lavdopts vstats" and then analysing the
> data, looking for areas where the instantaneous bitrate drops for
> two seconds.  However, this is likely to lead to plenty of false
> positives, and I'm not even sure if it would work anyway.
>
> Has someone come across this problem before?  Do you have any
> suggestions to help me?  Thanks in advance!

Try -vf blackframe. You'll need to compile mplayer from svn, since it is a 
recent addition.