Posterization

For the basketball slang term about dunking over an opponent, see Posterized.
Example of a photograph in JPEG format (24-bit color or 16.7 million colors) before posterization, contrasting the result of saving to GIF format (256 colors). Posterization occurs across the image, but is most obvious in areas of subtle variation in tone.
Posterized photo of a hibiscus
Posterized photo

Posterization or posterisation of an image is the conversion of a continuous gradation of tone to several regions of fewer tones, causing abrupt changes from one tone to another.[1] This was originally done with photographic processes to create posters. It can now be done photographically or with digital image processing, and may be deliberate or an unintended artifact of color quantization. Posterization is often the first step in vectorization (tracing) of an image.

  1. ^ Chao, Cheng-Kang Ted (15 July 2021). "PosterChild: Blend-Aware Artistic Posterization" (PDF). Computer Graphics Forum. 40 (4): 87. doi:10.1111/cgf.14343. Retrieved 19 April 2024.