Videos Inside a Scene

A Scene is a web page (an HTML file, or a folder with an index.html) that Wallpaper Reactor renders exactly as you wrote it. If your Scene plays its own video, that video must be VP9 in a WebM container. Wallpaper Reactor refuses to create the wallpaper otherwise.

Why the rule exists

• A Scene is rendered as authored. The app cannot swap your page’s <video> element for a player it controls.
• The desktop engine ships without the H.264 and H.265 decoders, so those videos would show as a black rectangle.
• AV1 plays in the desktop engine, but macOS decodes it only on recent Apple silicon, so on many Macs it would also show as a black rectangle.
• VP9 plays on every desktop platform, but on macOS only inside WebM. VP9 in an MP4 is refused for that reason.

This rule applies only to videos inside a Scene. A plain Video wallpaper is unaffected, and H.264 in MP4 stays the recommended format there.

Encode your video

Run this before you add the video to your Scene:

ffmpeg -i clip.mp4 -c:v libvpx-vp9 -b:v 0 -crf 31 -c:a libopus clip.webm

• -c:v libvpx-vp9 -b:v 0 -crf 31 encodes constant-quality VP9. Lower the -crf number for higher quality and a larger file.
• -c:a libopus encodes the audio as Opus, the audio codec WebM carries. Add -an instead if the video has no sound you need.

Then point your page at the .webm file, and make sure the old .mp4 is no longer in the folder.

What Wallpaper Reactor checks

The check reads the bytes of every video file in your Scene, so renaming a file’s extension does not get past it. If a video does not qualify, creation stops and shows the file name, what it found (for example H.264/MP4), and the same ffmpeg command with your file’s name filled in. The app checks for VP9 in WebM; a VP8 WebM also passes.

If you see this error, run the command it shows and add the new .webm file to your Scene.

Related

• Creating a wallpaper for the full Scene requirements
• Customizable User Settings to give your Scene options
• Wallpaper Upload Guidelines