Macroblock

Each macroblock consists of a 16 x 16 array of luma (Y)  pixels (4 blocks). The number of chroma pixels (Cr, Cb) will vary depending upon the chroma pixel structure indicated in the sequence header.

The macroblock is the fundamental unit for motion compensation and will have motion vector(s) associated with it if is predictively coded.

A macroblock is also classified as field coded or frame coded depending on how the four blocks are extracted from it. See Field DCT Coding and Frame DCT Coding.

A slice  is composed of a series of macroblocks.

 

MPEG 2 Video Data Structures Topics:

- PIXEL

- BLOCK

- MACROBLOCK

- Field DCT Coding and Frame DCT Coding

- SLICE

- PICTURE

- GROUP of PICTURES (GOP)

- SEQUENCE

- PACKETIZED ELEMENTARY STREAM

Up to MPEG 2 Video Data Structures