How to plan a live event video system
1. Start with the screens
For each destination write down what it needs to receive: pixel size, frame rate and the connector it takes. An LED wall is cabinets times pixels per cabinet: 22 × 9 cabinets of 192 pixels is a 4224 × 1728 canvas. A projection blend is the projectors' pixels minus the overlap. A canvas too big for one output is split across several, and each output then needs its own timing and EDID (custom EDIDs for LED processors and media servers).
2. Pick one show rate
Match your sync source: 59.94 or 50 Hz when the system is locked to broadcast or house sync, 60 otherwise. Everything that is switched or mixed together should run at the same rate, so choose it once and hold every source and display to it. The calculator's exact-refresh clocks land on 59.94 and 29.97 Hz properly (how the pixel clock sets the refresh rate).
3. List the sources
For each source note the connector it actually has and the format it will output: size, rate, bit depth and color format. A laptop, a media server and a camera rarely start in the same family, which is why the next two steps matter.
4. Check every link
A link either carries the signal or it doesn't, and the weakest one in the chain decides. Check every cable, not just the first. This is what the common show formats need (standard CTA-861 timing, calculated by the same engine as the calculator):
| Format | SDI link needed | HDMI 2.0 | HDMI 2.1 | DisplayPort 1.2 | DisplayPort 1.4 |
|---|---|---|---|---|---|
| 1080p59.94 · 8-bit RGB | 6G-SDI | Fits · 25% | Fits · 8% | Fits · 21% | Fits · 14% |
| 1080p59.94 · 10-bit 4:2:2 | 3G-SDI | Fits · 25% | Fits · 8% | Fits · 17% | Fits · 11% |
| 2160p59.94 · 10-bit 4:2:2 | 12G-SDI | At the limit · 99% | Fits · 33% | Fits · 69% | Fits · 46% |
| 2160p59.94 · 8-bit RGB | Check | At the limit · 99% | Fits · 33% | Fits · 82% | Fits · 55% |
SDI links have no headroom: a format maps to a fixed link, so the table names the link instead of a percentage. 8-bit sources travel as 10-bit on SDI. "Check" means the format isn't in the SMPTE mapping tables the calculator uses, so look at the equipment's data sheet. The percentages on HDMI and DisplayPort show how much of each link the signal uses. More detail: 4K60 over HDMI and DisplayPort.
5. Count the converters
A converter is needed wherever the signal family changes (HDMI into SDI, DisplayPort into SDI) or the physical socket differs, such as USB-C into a full-size DisplayPort input. A different version of the same socket doesn't need one: DisplayPort 1.2 into 1.4, or 12G-SDI into 3G-SDI. Treat each converter as a piece of gear in its own right. It goes on the equipment order, and the cables into and out of it are two cables in the schedule.
6. Route and label
When many sources have to reach many destinations, put a router in the middle and a screen switcher in front of the screens. Label every router input and output with the source or destination it carries, so the person at the router and the person at the screen are using the same names.
7. Number the cables
Give every cable a number and, if you can, a length. The numbers and lengths drive the cable schedule, the cable labels and the equipment order: video cable schedule and labels.
8. Draw it
A signal flow diagram reads left to right: sources, production, routing, screen switcher, destinations. Each box lists its ports and each line lands on the port it is patched to, so anyone can follow a signal from the camera to the wall. Plot it on one sheet with a title block.
Checklist before load-in
- One show rate, the same on every source and display.
- Every link in the chain passes the check, including the ones after a converter.
- Every converter is on the equipment order, and the cables either side are in the schedule.
- Every cable is numbered and labeled at both ends.
- The equipment order matches the patch.
- Any source that must output a fixed size has the EDID it needs loaded.
Do it in the Signal Flow Planner
The Signal Flow Planner follows these steps: you patch the devices port by port, it runs the link check on every cable, flags a missing converter, draws the diagram and produces the cable schedule, equipment order and labels from the same patch. Try the live demo, a sample show you can rewire.