[XviD-devel] SAD vs MSE for ME (warning! acronym overflow!)

[Michael Niedermayer]

Hi

On Friday 06 September 2002 13:03, skal wrote:
> Hi Michael,
>
> On Fri, 2002-09-06 at 13:05, Michael Niedermayer wrote:
> > perhaps u want to take a look at motion_est.c in ffmpeg CVS it does
> > halfpel search with only 4 instead of 8 checks
> >
> > its based upon one assumtation:
> > that the score of the comparissions can be well approximated by axy +
> > bx^2 + cy^2 + dx + ey + f(type)
> > type is the interpolation type (none, horizontal, vertical, both)
>
> 	this looks pretty nice. What do you use as 'score()' function?
> 	SAD or SSD? SSD would maybe fit better the 2nd order 	approximation
> since it is quadratic itself...
we use SAD currently ...

> 	And does it extend to qpel search? Do you need additional
> 	check points to ensure good error bounds?
i didnt try qpel yet, ffmpeg doesnt support qpel encoding yet ...

[...]

Michael