[XviD-devel] pre-processing

[Marc FD]

> > You can't say it like that. To decide if size difference is better than
> > PSNR drop, you should test at constant bitrate mode for that.
> >
> > But for preprocessing this is not really good, either. So maybe 12% size
> > difference is very good, if the visual quality doesn't get worse.
> >
> > gruel
> >
> >
>
> constant bitrate ?

I tested and it gives me -0.2 Db PSNR on CBR (with -5% size)
but i see two problems in this test :
- It's a sort of Pre-Processing, so it's reducing noise. for the eye, it's
better, but it's worse PSNR-wise.
- I'm using a too big bitrate (900 kbps) , so the quantizers are too low and
the impact of the pre-processing is vicious.

I'll make beta-testing. if the users see an improvement, we could add it
optionnaly (tested on anime) or hard-coded (if it works with movies too)

the idea of my pre processing is to increase the TOO_SMALLLIMIT (based on
ssd) when a MB doesn't move at all. so noise between 2 identical MBs isn't
coded. i have no smearing, so it's seems to work well.