17xande.dev web2sdi

Getting started

Install it, point it at a page, and get it on the wire.

What you need

  • A Windows PC with a Blackmagic DeckLink card. Development and verification were done on a DeckLink Duo 2.
  • Blackmagic Desktop Video, the card's driver. This is the only prerequisite: web2sdi talks to the card through the driver's COM registration and ships no DeckLink DLL of its own.
  • Something to plug the SDI output into — a monitor, a switcher, a recorder.

Install

Run web2sdi-setup-<version>.exe. It installs to C:\Program Files\web2sdi, adds Start Menu and Desktop shortcuts, and opens TCP port 8787 in the firewall for the control page. It warns if Desktop Video is missing.

It also offers a Startup shortcut. Take it if this box is going to live in a rack: after a power cut or a reboot, it comes back on air by itself, on the page it was last showing.

For an unattended install, /S installs silently:

web2sdi-setup-0.1.0.exe /S

Uninstalling removes everything except your settings in %APPDATA%\web2sdi.

First run

Start web2sdi from the Start Menu. A tray icon appears; it opens the control page and is the clean way to quit. Only one copy runs at a time — two would fight over one SDI output.

The control page is at http://127.0.0.1:8787/. On first run it shows https://example.com in 1080p59.94 on device 0.

  1. Type the page you want on air into Source → URL and press Apply. The preview shows what the browser is rendering.
  2. If the page needs a click or a login, switch on Interact in the preview's header. Your mouse and keyboard go to the page — which is live to air, so the preview gets an amber outline while you do it.
  3. If the page has a <video>, a Video card appears with seek, skip, play and pause, mute and rate.
  4. Open Settings to change the SDI mode, device, or turn on embedded audio.

The badge in the top bar says whether the output is running. If it is not, the Source card says why — a card that is missing or busy does not stop the browser, the preview or the control page from coming up.

Reaching it from another machine

By default the control page only answers on this machine. To drive it from elsewhere on the network:

web2sdi.exe --lan --port 8787

There is no password: anyone who can reach the page can change what goes to air. Put the box somewhere only operators can reach — its own VLAN, say.

Pages and video

Chromium's official builds, which web2sdi uses, have no H.264 or AAC. An .mp4 renders as a black frame, reports a duration of zero and logs nothing. Use WebM (VP8/VP9 video, Opus/Vorbis audio) for anything you play locally, and expect the same from any site that only serves H.264.

The control page drives the first <video> in the page's main frame. A video inside a cross-origin iframe — a YouTube embed, for instance — is out of its reach. Dropdowns, date pickers and autocomplete lists do render, both in the preview and on the wire.