[Ffmpeg-devel] ratecontrol experimentation

[Loren Merritt]

On Mon, 13 Feb 2006, Corey Hickey wrote:

> I've been messing around with ratecontrol and analysis thereof. The
> results don't really fit well in an email, so I put together a small web
> page.
>
> http://fatooh.org/ratecontrol/
>
> I'd appreciate any feedback. I'm starting to have good results, and some
> suggestions might point me in the right direction for even better results.

Can pTex serve the same purpose as mcVar?

In 2pass.log I see mc-var on the same order of magnitude as *tex 
(depending on quantizer). The value of mcVar seen by the vrc_eq is 
(mc-var / mb_num) where mb_num=880 at your resolution. So your factor of 
10^8 should still by 10^5 times bigger than tex, and make the equation 
equivalent to vrc_eq="mcVar^qComp". Which is a valid choice, but is it 
what you meant?

> for i in 1:turbo:vb_strategy=2 2 ; do
>   mencoder matrix.vob -aid 128 -oac copy -vf \
>   crop=718:356:0:60,scale=640:272 -sws 9 -ovc lavc -lavcopts \
>   vcodec=mpeg4:vbitrate=581:psnr:vpass=$i:mbd=2:mv0:trell:cbp:\
>   precmp=2:cmp=2:subcmp=2:predia=2:dia=2:preme=2:vme=5:v4mv:\
>   last_pred=2:vqcomp=0.6:qpel:sc_factor=6 -ofps 24000/1001 -o
>   lavc-default.avi
> done

Is that the exact command you ran? My copy of bash retains the spaces at 
the beginning of the line when collapsing \'s, thus treating last 2 lines 
of the lavcopts as input filenames (which obviously won't exist).

Also, I see vb_strategy but no vmax_b_frames.

--Loren Merritt