Bug 246792 – Laggy Animated WEBP Rendering

• Status: RESOLVED
• Resolution: MOVED
• Component: Images

Created attachment 463108 [details]
Chrome vs Safari rendering the same animated WEBP

Safari has full support for the WEBP and animated WEBP image format (reference - https://caniuse.com/webp). However,  rendering of larger animated WEBP files are extremely janky, to the extent that the image is unviewable. A ~10MB, 1600 × 1039px and 15FPS animated WEBP encoded with FFMPEG exhibits this issue, as seen in https://github.com/SwiftcordApp/Swiftcord/blob/main/README.md. Rendering starts out mildly laggy (frame skips, each frame takes too long to render), then quickly descends into a slideshow. Viewing the same website on Chrome works perfectly, which shows that this isn't an encoding issue. I've tested with smaller animated WEBP images and found that smaller images slow down the onset of lag.

A screen recording demonstrating the same website on Chrome and Safari helps illustrate the issue. I've only reproduced this bug on my machine, a 2021 14" MBP.

Created attachment 463110 [details]
Chrome vs Safari rendering the same animated WEBP (compressed)

Compressed for easier viewing

[Radar WebKit Bug Importer]

<rdar://problem/101399610>

[Said Abou-Hallawa]

rdar://100568410

[Said Abou-Hallawa]

This also can be seen in this image https://makeavideo.studio/assets/style1.webp

[Said Abou-Hallawa]

This is a bug in a system framework below webkit.

[Said Abou-Hallawa]

*** Bug 247414 has been marked as a duplicate of this bug. ***