Screen sync: SignalRGB + WLED
Make the LEDs follow what is on your screen. Install SignalRGB on Windows, add the WLED device, map the layout, and tune it so it feels instant.
This is the part people film. The lights stop being a colour and start being an extension of the screen — the room fills with whatever is on the panel, half a frame behind it.
1. Get WLED ready to receive
Open your WLED device and go to Config → Sync Interfaces. Enable the realtime receivers — DDP is the one to prefer, and E1.31 (sACN) is the fallback if your version of SignalRGB asks for it. Set the realtime timeout to about 2500 ms so the strip returns to its own effects a couple of seconds after the PC stops sending.
Write down the controller's IP address — it is on the WLED info page. Then go to your router and reserve that IP for the controller (usually called DHCP reservation or static lease). If you skip this, the router will hand the ESP32 a different address one day and your sync will silently stop working.
2. Install SignalRGB
Download it from signalrgb.com
Take the free version. Everything you need for WLED screen mirroring is in it.
Let it finish its first-run scan
It enumerates your RGB hardware on first launch and can take a minute. Let it finish before you add anything.
Allow it through the Windows firewall
When Windows asks, tick Private networks. SignalRGB talks to the controller over UDP on your LAN; blocked at the firewall, the device will appear connected and simply never light up.
3. Add the WLED device
In SignalRGB open Devices and look for the option to add a network or WLED device (the exact wording moves between versions — it is under Devices, sometimes behind an "Add Device" or "Network Devices" button). Enter the IP address you reserved. The device should appear with its LED count read from WLED.
4. Map the layout
This is what separates a sync that looks right from one that looks broken. SignalRGB has a canvas that represents your screen; you place the device on it so each LED knows which part of the picture it is showing.
Open the layout canvas
Find your WLED device in the layout view. It will appear as a strip of LEDs you can position, rotate and bend.
Wrap it around the monitor rectangle
Arrange the LEDs around the edge of the screen in the same order the physical strip runs — starting at the bottom-right and going anti-clockwise, if you followed the layout diagram. Order matters more than exact position.
Set the first LED where your data enters
LED number one in SignalRGB must be the LED nearest the controller. If your whole ambilight looks rotated — the top edge showing what is on the left of the screen — this is why.
Save the layout
Then pick the screen-mirror effect (it is usually called Screen Mirror, Ambient or similar) and point it at the display you actually watch.
5. Tune it
| Symptom | Setting to change | What to do |
|---|---|---|
| Lights lag noticeably behind the picture | Capture rate / FPS | Raise it. 30–60 FPS feels instant; below 20 you see it trailing. |
| Colours wash out to a muddy grey | Saturation boost | Increase saturation. Averaged screen content is naturally desaturated. |
| Too bright for a dark room | Brightness in WLED, not SignalRGB | Set the ceiling in WLED so every effect respects it. |
| Flickers on fast content | Smoothing / blur | Add a little smoothing. Some frame-to-frame averaging is worth the tiny extra latency. |
| Black bars on a film make the edges go dark | Capture area / crop | Crop the capture region to the actual picture, excluding the letterbox. |
6. When you switch the PC off
After the realtime timeout expires, WLED goes back to whatever effect and preset it had before. Set a preset you actually like as the default — a slow warm gradient at low brightness is a good idle state — so the TV wall still looks deliberate when the PC is asleep.