Term used to describe the process by which an image file is reduced by throwing away sampled points. If an image array consisted of 100 samples on the X axis and 100 samples on the Y axis, and every other sample where thrown away, the image file is decimated by a factor of 2 and the size of the file is reduced by 1/4. If only one sample out of every four is saved, the decimation factor is 4 and the file size is 1/16 of the original. Decimation is a low-cost way of compressing video files and is found in many low-cost systems. Decimation however introduces many artefacts that are unacceptable in higher-cost systems.