Dithering

Dithering is a technique to convert a grayscale image to black and white. It is used to create an illusion of the color which is actually not present. Dithering is done by randomly arranging the pixels.

Dither is applied in the form of noise to prevent quantization error.

Below image have different levels of dithering.

There are three types of dithering methods:

1. Random dither
2. Ordered dither
3. Error diffusion dither

Random dither

In random dither, errors appear as a noise.

Ordered dither

In ordered dither, error occurs randomly in the form of pseudo.

Error diffusion dither

In error diffusion dither, error occurs over in the neighbor pixel.