Scoreboard through a capture card

The simple test

Open the Windows Camera app. If your capture card shows up there and you can see the picture, UniversoOCR will see it too — it reads the card the same way any other Windows program does. That covers essentially every USB card: Elgato, AVerMedia, Magewell, Cam Link, cheap unbranded HDMI sticks, and internal PCIe cards that install a video device.

The same applies to SDI cards — what matters is that Windows presents it as a camera, not which connector is on the back.

Set the resolution — this one is important

Under Source there is a resolution setting: Auto, 720p, 1080p, 1440p or 4K. On a capture card it is worth setting deliberately.

A scoreboard at the far end of a hall occupies a small part of the frame. At 720p the clock digits may be twenty pixels tall, and twenty pixels is not much to decide whether a segment is lit. At 1080p the same digits are half as tall again, and the reading gets noticeably steadier.

The resolution takes effect on the next Start, not immediately — stop and start the source after changing it.

Set-up

1. Plug the card in and confirm the picture in the Windows Camera app.
2. Close any other program holding the card — most importantly OBS.
3. In UniversoOCR: open Source and pick the card — normally under Capture cards, though an unbranded stick with an odd name can land under Cameras. Choose a resolution, then press Start.
4. Define Corners over the board, then Add Field for the clock and the score.
5. Turn on OBS WebSocket, the vMix API, a file output or a browser overlay — they all run at once.

The one real problem: two programs, one card

Windows lets only one program open a capture device at a time. If OBS is already using the card, UniversoOCR cannot have it — the source list marks it In use rather than letting you find out from an error after pressing Start.

Four ways out, cheapest first:

• A separate camera for the board. Usually the best answer anyway. The scoreboard does not need a broadcast camera — a plain USB webcam on a tripod, pointed at the board and left alone, costs very little and never competes with your program feed.
• Send it back out as NDI. OBS with the NDI output plugin can re-share the feed it already has, and UniversoOCR reads that instead. See NDI.
• An HDMI splitter into a second, cheap capture stick.
• A card that allows several programs at once. Some do; most consumer sticks do not.

Getting a clean picture

• Fill the frame. Zoom in on the board. Do not read it from a wide shot of the court.
• Lock the camera down. A tripod. If the shot drifts, the marked fields drift off the digits.
• Watch for glare. Reflections on the board's cover are the usual reason digits fail to read, not the card and not the software.
• Avoid a wobbly angle. An angle is fine — Define Corners straightens it — but it must stay put.