[MEncoder-users] MPEG-2: vrc_minrate and vqmin / lmin

[Nicolas Hesler]

 lmin < vqmin.
> vrc_minrate sets minimum bitrate.
> I can only guess, that by setting vrc_minrate > 0, you (somehow) 
> prevent 
> big quantizers (which would lead to low bitrates).


My initial testing was flawed in that I assumed that vqmin and lmin were necessary in reducing the blocking.
In actuality vrc_minrate>0 seems to be a more important factor.  As soon as I raise vrc_minrate above 0 the blocking more or less disappears whether I change the values of vqmin/lmin/vqmax or not.   

Can someone explain this further?   

Why would raising the minrate cause such an "improvement" in deblocking/image quality? 

What does the warning mean, why did the developers put such a message in there?? : [mpeg2video @ 00D85BA0]Warning min_rate > 0 but min_rate != max_rate
isn't recommended!