Again, in order to prevent large-scale patterns (such as false contours), an intentionally applied form of noise is used to randomize the quantization error. This process is known as dithering. The Floyd-Steinberg algorithm implements dithering using the error diffusion technique—in other words, it pushes (adds) the residual quantization error of a pixel onto its neighboring pixels, to be dealt with later. It spreads the quantization error out according to the distribution shown in the following screenshot, as a map of the neighboring pixels:
In the previous screenshot, the current pixel is represented ...
