[MPlayer-dev-eng] comprehensive lavcopts test - in progress.

[Roman Gaufman]

Cant say I see your point.

From your results I can tell that 
[dia=-2,predia=-2] and [dia=2,predia=2]

or:
[dia=-1,predia=-1] and [dia=2,predia=2]

dont have an PSNR change.

Do you have tests for them individually without all the other args? Wouldn't 
they give you the same findings?

Also, what type of file are you testing, PSNR value is very different with 
different bitrate, with different input type, like animation or video, slow 
motion or high motion.

On Monday 14 June 2004 15:58, Romain Dolbeau wrote:
> Michael Niedermayer wrote:
> > btw, it would be interresting to know how many local minima are there in
> > your results
> > i mean cases where no single changed option leaded to an improvement
>
> that would be local maxima wrt PSNR ?
>
> That would be 3 if I'm not wrong:
>
> [cmp=6, dia=2, mbd=2, mv0, precmp=6, predia=2, qpel, subcmp=6, trell, v4mv,
> vmax_b_frames=0, vme=4]:44.63 [cmp=3, dia=-2, mbd=2, mv0, precmp=3,
> predia=-2, qpel, subcmp=3, trell, v4mv, vmax_b_frames=1, vme=4]:44.65
> [cmp=3, dia=2, mbd=2, mv0, precmp=3, predia=2, qpel, subcmp=3, trell, v4mv,
> vmax_b_frames=1, vme=4]:44.65
>
> You can't go from the first to one of the other 2 with
> only 1 change, and the last two are the same, PSNR-wise.
>
> The opposite (local minima for PSNR, i.e. you can't worsen
> the result with 1 change):
>
> [cmp=0, dia=2, mbd=2, precmp=0, predia=2, qprd, subcmp=0, vmax_b_frames=1,
> vme=4]:42.75 [cmp=0, dia=-1, mbd=2, precmp=0, predia=-1, qprd, subcmp=0,
> vmax_b_frames=1, vme=4]:42.75 [cbp, cmp=0, dia=-1, mbd=2, precmp=0,
> predia=-1, qprd, subcmp=0, trell, vmax_b_frames=1, vme=4]:42.96 [cbp,
> cmp=0, dia=2, mbd=2, precmp=0, predia=2, qprd, subcmp=0, trell,
> vmax_b_frames=1, vme=4]:42.96
>
> But those are not very useful in practice :-)
>
> (this is from the 2352 results vme=4, mbd=2)