[x264-devel] Re: [PATCH] PSNR averages

[Måns Rullgård]

Laurent Aimar <fenrir at via.ecp.fr> writes:

>> I was thinking on a lower level.  To calculate the PSNR, the quantized
>> samples must be dequantized and inverse transformed, as is done in
>> various places.  Is the reconstructed image needed for other reasons
>> than statistics?  Otherwise I suppose some cycles could be gained by
>> skipping these steps.
>  The quatif/dequant has to be done anyway (as the encoder need the
> reconstructed picture to do the MC).

Yes, of course.  I should have known better.

> Not doing PSNR will only save a SSE over the complete reconstructed
> picture.

That still saves a couple percent time.

-- 
Måns Rullgård
mru at mru.ath.cx

-- 
This is the x264-devel mailing-list
If you are in trouble, please contact <postmaster at videolan.org>