LedBanner Multicast Receiver

See the 80x8 LED banner at RevSpace on your own screen, from anywhere on the hackerspace WiFi. This little C/SDL3 app joins the same multicast group the physical display listens to, decodes each RGB565 frame, and paints it pixel-for-pixel in a scaled window. No extra hardware needed - just the network stream the banner already broadcasts.

What you get

• An SDL3 window rendering the live 80x8 banner, scaled 8x
• A multicast socket module that joins the group and validates 1280-byte frames
• Per-frame RGB565 to RGB decoding
• A Game of Life sender to exercise the receiver without the real banner

The data path

Each frame arrives on the multicast group as 1280 bytes of raw RGB565. The app checks the size, decodes the 2-byte pixels to RGB, and writes them into an 80x8 buffer. Then it renders that buffer scaled 8x in the SDL window. Stats land on the console: bytes, FPS, kB/s. Decoding RGB565 is the only transformation the frames get.