What does Motion vector mean?
A motion vector describes an estimated displacement used in motion-compensated video prediction. It helps an encoder and decoder relate regions across pictures rather than storing every new image entirely from scratch.
Why it matters
The estimate serves compression; it is not necessarily a measurement of an object’s true physical movement. Camera motion, overlapping objects and newly revealed backgrounds complicate prediction. Good coding can use these relationships efficiently, while difficult scenes still require additional information to avoid visible errors. A viewer should not confuse codec motion vectors with a television’s separately estimated interpolation frames.
A practical example
During a slow pan across a building, much of the image shifts predictably and can be represented efficiently. A crowd waving flags introduces more irregular changes. That helps explain why two scenes at the same resolution and nominal data rate can retain very different amounts of clean texture.
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Related terminology: Motion interpolation, Multicast.
For practical setup and troubleshooting, browse the journal or support guides.