AVIF encoding can be very slow

[swissspidy]

Related:

• https://github.com/libvips/libvips/issues/2983

[swissspidy]

Maybe just because this is using libheif under the hood which isn't super fast?

Previously I used @jsquash/avif (removed in #257), which uses libavif with aom encoder instead.

Maybe I can partially undo #257 to do some testing/benchmarking.

Related useful links:

• https://publishing-project.rivendellweb.net/image-formats-for-the-web-heic-and-avif/
• https://apple.stackexchange.com/questions/452019/how-is-heic-image-decoding-very-fast-in-ios
• https://github.com/strukturag/libheif/issues/545
• https://github.com/AOMediaCodec/libavif#build-notes

[swissspidy]

Can tinker with the (CPU) effort config in vips. It defaults to 4 (equivalent to speed = 5). The lower the faster. So to match https://core.trac.wordpress.org/ticket/61758 it would need to be set to 2.