[MPlayer-dev-eng] [PATCH] synch to x264 r50 / mencgen

[Romain Dolbeau]

Loren Merritt wrote:

> Y,U,V,Avg are arithmetic means of the frame-wise PSNRs.
> PSNR is a log scale, so it's meaning to take a mean. Consider a video 
> where half the frames are supposed to be pure black (and were encoded 
> with no errors, PSNR=infinity but capped to 100), and the other half are 
> supposed to be detailed, but were encoded as black anyway (PSNR ~= 0). 
> x264's Y,U,V,Avg PSNRs will all be 50 (i.e. good quality), even though 
> the video sucks. Global (calculated the same way as lavc's and xvid's 
> PSNR) will be about 3.

Ok, lots of thanks for the explanations. It make senses to me now :-)

Is that proper 'Global' values available for the other 2 encoders that
mencgen support, i.e. XviD and lavc ? From the line I parse, I only
see Y/Cb/Cr/All for lavc, and Y/U/V  for XviD...

-- 
Romain Dolbeau
<dolbeau at caps-entreprise.com>