Adaptive Quantization

[donkeykong]

Can anyone explain to a thicko (me) what Adaptive Quantization means in english

[Ethlred]

The main thing it does is re-balance the way bits are allocated so that more are used in the dark sorta flat areas. X264 had a rather nasty habit in areas with not quite flat lighting of not using enough bits and that resulted in gradients that had steps instead of being smooth. It annoyed me and obviously others didn't care for it either.

http://mewiki.project357.com/wiki/X264_Settings#aq-mode

aq-mode

Adaptive Quantization Mode

Default: 1

Without AQ, x264 tends to underallocate bits to less-detailed sections. AQ is used to better distribute the available bits between all macroblocks in the video. This setting changes what scope AQ re-arranges bits in:

0: Do not use AQ at all.
1: Allow AQ to redistribute bits across the whole video and within frames.
2: Auto-variance AQ (experimental) which attempts to adapt strength per-frame.

So I recommend using it. Blocky shadows and walls bug me. I have only used a setting of 1 so far, haven't tried the 2: Auto-variance setting and I leave the strength at the default of 1.

Ethelred