[MEncoder-users] [BUG] non-deterministic PSNR calculation with -lavcopts threads=2

[Michael Niedermayer]

Hi

On Tue, Dec 06, 2005 at 05:07:14PM -0800, Corey Hickey wrote:
> I'm currently in the final stage of preparing an lavc mpeg-4 mencoder
> command for Doom9: testing threads=2 and seeing how much quality is
> lost. I have a full encode going right now, but meanwhile I've been
> testing a short clip.
> 
> Quality is visibly a bit lower on the clip I tested when two threads are
> used, but, oddly enough, the PSNR shown is not only about 4-5% higher,
> but varies somewhat each time I run mencoder. The output file is the
> same each time, however, so the encoding itself should be correct.
> 
> I haven't used TOOLS/psnr-video.sh yet to see what the PSNR really is,
> but the variation didn't look right.

the variation should be fixed

[...]
-- 
Michael