Multihypothesis pictures are related to B pictures where
two motion-compensated signals from previous and future
reference frames are linearly combined for prediction.
Multihypothesis pictures also linearly combine two
motion-compensated signals but only from temporally
previous reference frames. Consequently, multihypothesis
pictures have the advantage that there is no extra coding
delay like for B pictures. In addition, multihypothesis
pictures are also used for reference to predict future
multihypothesis pictures. We integrate multihypothesis
prediction into the emerging H.26L standard by introducing
one additional multihypothesis macroblock mode for low delay
video coding which is similar to the bi-directional
macroblock mode for B pictures. The current implementation
achieves bit-rate savings up to 13% for the investigated
test-sequences when compared to the H.26L test model.
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