Four days ago, YouTuber ChromaLock uploaded a build log of his latest hardware project on his channel. This time, he showcased a Game Boy Color capable of playing back video through its original link cable via a Raspberry Pi Pico and custom software optimized for the workload.
Generally, simpler video means higher playback FPS— with surprisingly good clarity and smoothness for a connected USB webcam versus the classic Game Boy Camera accessory— but most videos are best played in monochrome since colors are limited to a palette of 4 and make videos even harder to run on Game Boy Color's 160 x 144-pixel display.
The final streaming utility intended to be used with a Raspberry Pi Pico, Game Boy Color, and link cable is an app called CGBLinkVideo, uploaded to GitHub by ChromaLock and built based on some other open-source software. The video compression operations reduce video quality to 1 Megabyte per second. Still, the Link Cable can only receive up to 64 Kilobytes per second, making the final video frames even more supremely compressed. This also makes phenomena like dropped frames or split frames far more common— but the playback does indeed overall "work."
The full ChromaLock video doesn't just demonstrate video playback—it includes detailed explanations of this tool's development around the Game Boy Color's system restrictions. Video playback can reach as high as 60 FPS when using grayscale or monochrome. When using color, video output is usually limited to about 12 FPS.
Some video game streaming was also tested, but even streaming original Game Boy games was a substantially worse experience than natively running applications, and modern 3D games like Doom Eternal were so high-resolution as to be unreadable on the Game Boy Color's archaic low-resolution display.
The main motivation of the project on ChromaLock's part just seemed to be pulling off a demonstration of the infamous Touhou Project music video "Bad Apple" being played back smoothly on a Game Boy Color. Since that video is already monochrome, getting it running at 60 FPS on a Game Boy Color actually turns out to be quite feasible, though there is some strong dithering present due to the streaming method.
