Export Formats Reference
Whiteboard Video Maker exports two formats — WebM video and animated GIF — both encoded in the browser. This page is the technical detail behind the export guide.
WebM video
| Property | Value |
|---|---|
| Container | WebM |
| Video codec | VP9 |
| Audio codec | Opus (when audio is included) |
| Encoder | WebCodecs API → webm-muxer |
| Fallback | MediaRecorder when WebCodecs is unavailable |
| Audio | Muxed in-browser into the WebM |
WebM is widely supported in modern browsers and on most platforms. It is the recommended output for publishing.
Animated GIF
| Property | Value |
|---|---|
| Format | Animated GIF |
| Encoder | gif.js (runs in a web worker) |
| Audio | None (GIF has no audio) |
| Color | Palette-limited (inherent to GIF) |
GIF is ideal for short, silent loops and embeds. File size grows quickly with length and resolution.
Resolutions
| Preset | Dimensions |
|---|---|
| 480p | 854 × 480 |
| 720p | 1280 × 720 |
| 1080p | 1920 × 1080 |
Quality
Low / medium / high control the encoder's bitrate/effort, trading file size against visual fidelity.
Why no MP4?
MP4/H.264 encoding in the browser is encumbered and not consistently available across browsers without large extra dependencies. WebM (VP9) is royalty-free and natively encodable via WebCodecs, which keeps the app free, dependency-light, and fully client-side. To get MP4, export WebM and convert it with any standard converter.
Browser support notes
- Chrome / Edge — best path; WebCodecs gives fast, high-quality WebM.
- Firefox / Safari — supported via the
MediaRecorderfallback; encode characteristics differ slightly. - Mobile web — supported; longer encodes are CPU-bound on the device.
Keep the tab in the foreground during export so the browser does not throttle the encoding worker.