n24-yt-multiviewer

Watch many YouTube livestreams at once — full-viewport video wall with priority rows, auto-fitting grid, and live-sync. Built for the Nürburgring 24h onboards.

▶ Live: https://n24.bbrks.me

Features

• Paste any number of YouTube livestream URLs (one per line) — watch?v=, youtu.be/, /live/, /embed/ and bare IDs are all accepted.
• Primary rows — prefix a line with * to pin it to a full-width primary row, or ** for a second full-width primary row below it. Primary tiles are rendered at native 16:9 with no letterboxing or gaps.
• Auto-fitting matrix — the remaining streams are laid out in the column count that keeps the 16:9 video as large as possible for the available space, recomputed on window resize.
• Autoplay muted with a one-shot sync-to-LIVE ~5s after load (seeks every player to the live edge so the views stay aligned).
• Fullscreen kiosk mode that auto-hides the control bar.
• Mute/unmute all in one click.

Usage

YouTube's IFrame API rejects a null origin, so it must be served over HTTP (not opened as a file://):

python3 -m http.server 8000

Then open http://localhost:8000/. The default N24 onboard streams are pre-filled; edit the list and click Load / Reload.

Hosting (Docker)

Static nginx image, no build step:

docker build -t n24-yt-multiviewer .
docker run -d --restart unless-stopped -p 8080:80 n24-yt-multiviewer

Then open http://localhost:8080/ (put it behind your own TLS-terminating reverse proxy / load balancer when hosting publicly).

Hotkeys

Key	Action
f	Toggle fullscreen
m	Mute / unmute all
h	Hide / show bar
s	Sync all to LIVE

Hotkeys are ignored while typing in the URL box.

Limitations

• Some channels disable off-site embedding (YouTube error 150/153) — nothing fixable client-side; drop/replace those URLs.
• Browsers only autoplay muted video; that's why streams start muted.
• Many simultaneous HD streams is heavy on CPU/bandwidth; YouTube picks adaptive quality.