Video compression picture types

B-frames use prediction from a (possibly weighted) average of two reference frames, one preceding and one succeeding.

Typically, pictures (frames) are segmented into macroblocks, and individual prediction types can be selected on a macroblock basis rather than being the same for the entire picture, as follows: Furthermore, in the H.264 video coding standard, the frame can be segmented into sequences of macroblocks called slices, and instead of using I, B and P-frame type selections, the encoder can choose the prediction style distinctly on each individual slice.

Also in H.264 are found several additional types of frames/slices: Multi‑frame motion estimation increases the quality of the video, while allowing the same compression ratio.

SI and SP frames (defined for the Extended Profile) improve error correction.

When such frames are used along with a smart decoder, it is possible to recover the broadcast streams of damaged DVDs.

Intra refresh periods of a half-second are common on such applications as digital television broadcast and DVD storage.