Browser support for frame-accurate compare playback
RemoteRoom compare is used from Review, including the unified Media & Review workspace that new rooms use by default. Ganged video compare has two browser paths: an exact WebCodecs path for frame-level control and a compatible video path when those browser APIs are not available.
Where compare lives now
New rooms use a single Media & Review page, where the file browser and review player can be enabled together or individually. Older rooms can still show separate Media Browser and Review tabs. In both layouts, compare belongs to the review player and supports side-by-side, wipe, and difference views.
Exact compare in modern browsers
For exact ganged video compare, RemoteRoom requests browser-playable H.264 full sources for both A and B. It then uses WebCodecs to decode paired frames and composites those frames onto one visible canvas. Because both sides are drawn by one frame engine, side-by-side, wipe, and difference views can stay tightly aligned.
Why Chrome is recommended
WebCodecs gives web applications low-level access to decoded video frames, and the exact compare player depends on browser support for APIs such as VideoDecoder and VideoFrame. Chrome and Chromium-based browsers currently provide the most reliable implementation for this workflow in our testing, especially for worker-based full-quality playback and canvas compositing.
Compatible fallback mode
If your browser does not expose the exact WebCodecs path, RemoteRoom falls back to compatible compare playback instead of blocking the session. This fallback uses normal browser video elements and clocks. It is useful for review continuity, while critical frame-accurate ganged decisions are best made in Chrome or another browser with reliable WebCodecs support.
What to check
If compare playback says it is preparing sources, one or both full browser-playable transcodes are still being generated. If compare playback says compatible mode is enabled, playback should continue, but very small timing differences can occur between the two sides.