Encode with a specific speed, where 0=slowest, 10=fastest, and 6=default

avifenc

AV1 Image File Format (AVIF) encoder.
More information: <https://aomediacodec.github.io/av1-avif/>.
Trick copyright: tl;dr; <https://github.com/tldr-pages/tldr>

avifenc --speed {{2}} {{path/to/image.png}} {{path/to/image.avif}}

click the source code to copy