Comment by spicyjpeg

Bayer dithering was also employed heavily on the original PlayStation. The PS1's GPU was capable of Gouraud shading with 24-bit color precision, but the limited capacity (1 MB) and bandwidth of VRAM made it preferable to use 16-bit framebuffers and textures. In an attempt to make the resulting color bands less noticeable, Sony thus added the ability to dither pixels written to the framebuffer on-the-fly using a 4x4 Bayer matrix hardcoded in the GPU [1]. On a period-accurate CRT TV using a cheap composite video cable, the picture would get blurred enough to hide away the dithering artifacts; obviously an emulator or a modern LCD TV will quickly reveal them, resulting in a distinct grainy look that is often replicated in modern "PS1-style" indie games.

Interestingly enough, despite the GPU being completely incapable of "true" 24-bit rendering, Sony decided to ship the PS1 with a 24-bit video DAC and the ability to display 24-bit framebuffers regardless. This ended up being used mainly for title screens and video playback, as the PS1's hardware MJPEG decoder retained support for 24-bit output.

[1]: https://psx-spx.consoledev.net/graphicsprocessingunitgpu/#24...