motion estimation

Motion perception is the process of inferring the speed and direction of objects and surfaces that move in a visual scene given some visual input. Although this process appears straightforward to most observers, it has proven to be a difficult problem from a computational perspective, and extraordinarily difficult to explain in terms of neural processing.
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(n.) The technique used to calculate the motion vectors in motion compensation. These motion vectors indicate how far and in which direction a macroblock has moved from one video frame to another. The MPEG and H.261 encoding standards do not dictate how these vectors are calculated.

An image compression technique that achieves compression by describing only the motion differences between adjacent frames, thus eliminating the need to convey redundant static picture information from frame to frame. Used in the MPEG standards.