[FFmpeg-user] decimate with dupthresh

[David Spreadborough]

Hi there,
would it be possible for someone to explain the dupthresh option for the decimate filter? 

I have a number of different formats with encoded duplicate frames. I cannot remove them with -vsync drop and then manage frame rate.
The duplicate rate varies so I am unable to use the cycle parameter.

The dupthresh option appears to be similar to that used with Mencoder. (I have used  -vf decimate=-0:99999 to remove all images that are exactly the same as the previous).

I would prefer to use ffmpeg and understand the dupthresh option a little better.

Thanks
David