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About this tool
The Multi-screen Player is a local preview tool for editing-style multi-region playback. It renders one composite canvas and splits it into several regions using preset layout templates. Drop in a local video file, pick one, or paste a URL into each region, then adjust how much space each region takes by dragging the separators. Use the transport bar to play, pause, restart or seek every region at once, and mute each region independently (all muted by default so multiple tracks do not pile up as one noisy mix). Switch the canvas ratio between 16:9, 9:16 and 1:1 to check how the edit looks in different frames. Everything runs locally in your browser with no uploads and no exports.
How to use
- Pick a layout template on the toolbar, such as Full, Two columns, Three vertical, 1 big + 2 small or a 2x2 grid.
- In each region, choose a local video file or paste a video URL, or drag and drop a file directly onto the region.
- Drag the separator bars between regions to adjust how much space each one takes.
- Use Play all, Pause all, Restart all and Seek to to control every region at once; toggle the mute button on each region to let only the tracks you want be heard.
- Switch the canvas ratio between 16:9, 9:16 and 1:1 to preview the layout in different frames.
Are my videos uploaded anywhere?
No. Everything runs entirely in your browser. Local files are turned into in-memory object URLs and never leave your machine.
Why does a pasted URL sometimes fail to play?
Some sources are blocked by CORS or hotlink protection, so the browser cannot fetch them. A local file is the most reliable option for monitoring.
Is playback frame-synchronized across regions?
No. Each video decodes on its own timeline. The tool only roughly triggers play, pause, restart and seek together; frame-accurate sync across media is not guaranteed and is a physical limit of in-browser multi-stream decoding.
Can I export the composite as a video file?
No. This is a live monitoring/preview tool only, with no export or recording.