ディザリング

Dithering arranges pixels of two or more available colors in patterns that the eye blends at a distance, perceiving a color that is not actually present in the palette. Common algorithms include Floyd-Steinberg (error diffusion) and ordered dithering (using a Bayer matrix). Dithering was essential in the era of limited color palettes (8-bit and 16-bit displays, GIF format) and remains important in certain contexts: reducing file sizes in GIF and PNG images, printing with limited ink colors, and creating a retro aesthetic. In modern design, dithering is occasionally used deliberately as a stylistic choice for texture and nostalgic visual effect.