In video compression, a motion vector is the key element in the motion estimation process. It is used to represent a macroblock in a picture based on the position of this macroblock (or a similar one) in another picture, called the reference picture.
The H.264/MPEG-4 AVC standard defines motion vector as:
motion vector: A two-dimensional vector used for inter prediction that provides an offset from the coordinates in the decoded picture to the coordinates in a reference picture.
... modes are referred to when a block is coded without sending residual error or motion vectors ... The decoder will deduce the motion vector of Direct/Skip Mode coded block from other blocks already decoded ... There are two ways to deduce the motion TEMPORAL It uses the block motion vector from List 1 frame, located at the same position to deduce the motion vector ...
... The blocks that stayed in the same relative position (read there was no motion in this part of the image) receive relatively little processing ... for a match to find out where the "block" went (if there's motion, the block obviously had to have gone somewhere..) ... at the immediate surrounding blocks (assuming little motion) ...
Famous quotes containing the word motion:
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