Macroblock: 16×16 Split in blocks: 8×8 Split in sub-blocks: 4×4

In H.264, each macroblock (16 x16 pixels) may be split into sub-macroblocks in four ways: one 16 x 16 sub-macroblock, two 16 x 8 sub-macroblocks, two 8 x 16 sub-macroblocks, or four 8 x 8 sub-macroblocks. If the 8 x 8 mode is chosen, each of the four 8 x 8 sub-macroblocks may be split further in four ways: one 8 x 8 partition, two 8 x 4 partitions, two 4 x 8 partitions or four 4 x 4 partitions.

Intra prediction works in 9 possible modes (encoder dependent)