[MPlayer-users] [BUG] naq & bframes can cause horrible results and bandwidth consumption

[Corey Hickey]

Jindrich Makovicka wrote:
> Hello,
> 
> I just found a reproducible case when usage of naq, *_mask and b-frames
> causes lavcodec produce terrible output. After the encoder encounters a
> high motion scene, or a scene with a lot of noise (as in the example),
> it starts producing a sequence of P & B frames, where P-frames are with
> low detail and blocky, while B-frames are with high detail. The
> resulting video looks extremely crappy for the rest of the file and the
> encoder starts consuming high amount of bandwidth, which doesn't
> decrease with time. Removing naq causes the problem disappear.
> 
> code used to reproduce the case:
> 
> #!/bin/sh
> 
> VCODEC="-ovc lavc -lavcopts vcodec=mpeg4:vbitrate=746:vlelim=-4:vcelim=7:\
> lumi_mask=0.05:dark_mask=0.01:scplx_mask=0.02:tcplx_mask=0.08:\
> mbd=2:vmax_b_frames=1:naq:vqmin=2"
> 
> mencoder -v -nosound $VCODEC -o out.avi test1.avi
> 
> input video is available at http://kmlinux.fjfi.cvut.cz/~makovick/test1.avi
> 

Unless Michael Niedermayer sees this here, you should forward the report
to the ffmpeg-devel list.

-Corey