[ENH]: Support avif as output format

[rotsee]

Problem

Since v3.6.0, Matplotlib supports webp output (yay!), but I couldn't find a ticket tracking Avif support, so here's a feature request for savefig to support saving as .avif.

relevant links:

• CanIUse
• Pillow pull request

Proposed solution

No response

[jklymak]

I think this would need to wait for pillow to support?

[ksunden]

While Pillow support is a prerequisite (and probably sufficient) condition for savefig to support AVIF, animations actually may have some support already.

Newer versions of ffmpeg support AVIF (though I could not test easily because the version in my distro's repository is too old).

The imagemagick writer did save an AVIF file. However, it may have only saved a single frame... (Not 100% sure if that is a viewer program problem or file output problem)

ani.save("test.avif", writer="imagemagick")

Gives: (zipped AVIF file because github doesn't allow AVIF directly)
test.zip

[github-actions]

Good first issue - notes for new contributors

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[fdintino]

Until that PR is merged you can use a separate package, pillow-avif-plugin, to allow Pillow to save AVIF images.