[theora] NHW Project - high compression -l4 setting

Raphael Canut

2018-02-19 15:24:56 UTC

Hello,

-l4 compression setting is still experimental, I like its
neatness/sharpness approach because the other codecs at equivalent
compression tend to blur image.Do you approve this approach?

On the other side, -l4 setting little lacks of precision, should raise the
quantization from 0.87 to something like 0.89-0.9, and then I would have to
compensate with for example more quantization on the DC parts or start to
increase "adaptively" the wavelet coeff threshold of the dead-zone.

-l3 setting seems to be good, even if I can still raise quantization to
0.89-0.9 and save bits on other parts...

As I said in my last post, when -l3 and especially -l4 settings will be
validated, I will create a new release 0.1.4 for the NHW Project, this is
for long overdue.-Even if there will not be all the improvements I wanted
to add, for example we can still save 1-2Ko in average per .nhw file...-

Many thanks!
Cheers,
Raphael

Post by Raphael Canut
Hello,
For those interested, I have added a -l4 high compression setting to the
NHW codec ( http://nhwcodec.blogspot.com/ ).This setting is very
experimental, I have boosted the sharpness for this one, but it can lack of
precision on low contrast areas.
This setting still maintains a good neatness and when it will be
validated, I will then make a new 0.1.4 version for the NHW Project.
High compression is really complex.Any help is welcome.
Cheers,
Raphael