After the initial touch around in this blog Lights up with blaze - RGB for RadiantGoofyBulbs and understanding the project idea here The Project Plan - RGB for RadiantGoofyBulbs , this blog explains the display colour extraction method done through Prismatic tool.
Prismatic + WLED: How Screen Colours Flow to the LEDs
1. Screen Color Capture
The Prismatic app runs on the computer and continuously captures the visible part of your display. It divides the screen into zones that correspond to each LED along the edges of the screen.
For every frame:
- It calculates the average colour of each zone
- Applies gamma correction and smoothing to ensure smooth transitions
Result is a list of RGB colour values, one per LED
2. Colour Mapping and Data Packaging
Prismatic has to know how the LEDs are arranged (top, bottom, left, right)
It maps each zone’s colour to a specific LED index and prepares a data packet that contains all RGB values
3. Wi-Fi Transmission to WLED
Prismatic sends this colour data wirelessly over the local network using UDP packets (fast, low-latency communication)
The controller running the firmware listens for these packets on a specific port and drives the associated addressable LEDs.
4. WLED Receives & Drives the LEDs
The RGB data is decoded and updates the corresponding LEDs in real time. The LEDs change colour hundreds of times per second, perfectly matching what’s happening on your display.
Prismatic Tool Setup and Configuration
That's about Prismatic functionality, stepwise configuration and in the next blog, we'll talk about the mechanical build up, painting and how the PCBs are put together to build LED towers.
