A term used in all mpeg video encoders, both software and hardware, which refers to the two 8x8 blocks of numbers appearing under the Quantize Matrix tab in the settings on some encoders or hard coded. These blocks of numbers represent the mathematical functions that the encoder will perform in order to best optimize the video for the appropriate format. Settings vary between a video being encoded as computer animation intended for a computer monitor or full motion video intended for a television. Different Matrix are used for progressive frame and interlaced and also the matrix varies (should) dependent on bit rate.

See also BLOCK and DCT