[FFmpeg-devel] [PATCH]lavf/decimate: Fix total difference for the first frame

[Carl Eugen Hoyos]

Derek Buitenhuis <derek.buitenhuis <at> gmail.com> writes:

> 
> On 1/3/2016 3:11 PM, Carl Eugen Hoyos wrote:
> > With the patch, the frame with the lowest diff is actually dropped 
> > instead of the first frame that indicates a scene change without 
> > the patch (iiuc).
> 
> Is this for all scene changes or just frame 0? If for all 
> scene changes, ignore the lower comment.

Afaict, prv==NULL only for the the first frame.

> > -        dm->queue[dm->fid].totdiff  = INT64_MAX;
> > +        dm->queue[dm->fid].totdiff  = dm->scthresh;
> 
> Upstream uses +1 here, but I'm not sure why:

"dm->scthresh+1" is equivalent to INT_MAX afaict and 
makes the given sample fail with our decimate filter.

Carl Eugen