Extend the range of "speed" option in avif output params

[janaz]

There's a new speed setting added to aom in v 3.0.0

New speed 9 setting for faster realtime encoding.

This tiny PR extends the speed range for avif output from 0..8 to 0..9

[coveralls]

Coverage remained the same at 100.0% when pulling ddf0336 on janaz:aom-speed9 into 861cd93 on lovell:bijou.

[janaz]

It seems that the "FreeBSD 13.0" check is currently broken on the "bijou" branch, so most likely the failing test is not caused by my change

[lovell]

Hi Tomasz, good to hear from you, thanks for the PR.

Have you been able to test this with libvips? I ask as there's currently a 0-8 range limit on the speed parameter that will probably need lifting first:

https://github.com/libvips/libvips/blob/77ccd04cbe3939c5680b1b4e0aeebbb71febd6d8/libvips/foreign/heifsave.c#L509-L514

(See also libvips/libvips#1819, which introduced the feature and has some discussion about what range would be suitable given the state of dependent libraries at that time.)

[janaz]

Hi Lovell,

I haven't tested the change with libvips, but I'm going to do that as soon as possible and report if it works or not. If there's a limit of speed=8 in libvips then obviously the change either won't have any effect or will raise an error. If that's the case then I'll try to compile patched libvips locally to do some further testing.

I don't think there's a limit for the speed setting in AVIF encoders. I might be wrong but it looks like the speed values just turn on or off some toggles in the encoder's algorithm and each encoder may define its own range for the speed setting. For that reason, it might be better not to limit it in libvips or sharp as future versions of aom of rav1e are likely to introduce yet another speed value.

[lovell]

It looks like this PR was auto-closed when I removed the work-in-progress bijou branch and now I don't appear to be able to reopen it or change the destination branch, sorry Tomasz. Please feel free to reopen when you're ready!