[FFmpeg-user] Libx265 halves the quality when psy-rd is enabled for 444 input.

[Aditya Dandavate]

On Mon, 1 Jan, 2024, 7:44 pm Ferdi Scholten, <ferdi at sttc-nlp.nl> wrote:

> On 31-12-2023 04:32, Aditya Dandavate wrote:
> >>> rd=3 psy-rd=2.00
> >> Those (default) values are probably too high for your purpose, creating
> >> artifarcts, ringing and blurring. Reduce them (1 is the recommended
> >> start setting).
> >>
> >> Read the documentation for it:
> >> https://x265.readthedocs.io/en/master/cli.html#psycho-visual-options
> >> _______________________________________________
> >>
> > -x265-params psy-rd=1.00 sets 'psy-rd to 1' but how to change '-rd' to
> '1' ?
> >
> >
> The same way,
>
> -x265-params psy-rd=1.00:rd=1
>
> rd accepts values 1..6 generally 1 has the fastest encoding and 6 is
> slowest. Where as 6 gives smaller size and 1 bigger size output.
>
> Experiment with settings until you find appropriate values.
> _______________________________________________
>

yes sir. Sure 👍

Also, in the documentation, I saw that there is a way to set cbQpOffset and
crQpOffset. When psy-rd is enabled for 444 input, both these values are set
to 6. What is their default setting ?
How can I force them to be at their default settings always ? Can you
please help me in this ?

Thanks 🙏

>