I wanted to display some logos on the RGB LED Matrix in view of the MacroFab Design Contest: Blink an LED. I decided to show the Hackaday Jolly Wrencher, the MacroFab logo and Mouser Electronics logo. I found all of these with a simple search, resized and edited them slightly:

The problem was that the Node-RED could only accept RGB values between 0 and 255, not a PNG file. I have yet to program a PNG parser in JavaScript, this wasn't the point of the task though.

I found this nice website that converted PNG images to XLSX files with the RGB pixel values from 0 to 255. The formatting wasn't quite right, so I applied some regex-fu and voilà: an illegible stream of numbers that, when sent to the RGB LED Matrix, would display the following logos:

I couldn't take a video as the update rate of the LED display gave a large black scan line when using my phone camera. That's not visible to the human eye though.