Convert user uploaded animated GIFs to videos

[swissspidy]

Feature Description

Since we now have all the pieces to do use FFmpeg in the editor and force cross-origin isolation, it would totally be possible to optimize a user-uploaded animated GIF by automatically turning it into an MP4. In the editor this would use the "hidden" GIF element we already use for Tenor GIFs (which are also actually videos).

Not only would it be possible, but it should also be quite trivial to implement:

During upload:

1. Upload GIF file
2. We check whether the GIF is animated (perhaps with something like https://gist.github.com/marckubischta/261ad8427a214022890b)
3. If GIF is animated, run through FFmpeg
4. Create GIF element with the video
5. Create poster image for the video

Existing images:

1. Just like for non-optimized videos, offer a button to optimize GIF, which will optimize it behind the scenes

Alternatives Considered

This might not be a high priority since not many users might be uploading animated GIFs to WordPress / stories.

Additional Context

Related: WordPress/gutenberg#19730

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Acceptance Criteria

Implementation Brief

[swissspidy]

cc @o-fernandez @pbakaus

[spacedmonkey]

This is an interesting read - https://github.com/cyburgee/ffmpeg-guide

[swissspidy]

Here's a proof-of-concept demo:

GIF.2.Video.mov

Poster generation works too, it's just not reflected in the media library yet.

The underlying data structure for GIF resources needs to be adapted a little bit, but it looks really promising already.

[spacedmonkey]

Is the poster image the originally uploaded image?

[swissspidy]

Is the poster image the originally uploaded image?

In my PoC the poster image is a freshly generated, still image of the video's first frame. Just using the GIF would negate any benefits of using videos in the first place, because the browser would then download a large GIF and a video, which would just make things worse.

[csossi]

poster not generated after video optimization completed for animated gif:

[swissspidy]

@csossi Well spotted! Since GIFs are technically images to the user's eyes, there's no poster image section under "Accessbility" for GIFs. This is the same behavior as today, when inserting a GIF from Tenor for example. So this is expected behavior.

[csossi]

Then all is well, @swissspidy

Verified in QA