05194908 is referenced by 47 patents and cites 11 patents.

In apparatus, such as a weapon sight, the speed of an object moving relative to a scene is determined by processing a plurality of successive frames of data, each obtained by scanning the scene, and detecting motion of the object relative to the background/foreground features of the scene. Each frame is compared with a reference comprising a different one of the frames and corresponding background features registered. Once the frames are registered, light intensity values of corresponding elements of the frames are subtracted. The registered background features, being stationary, cancel leaving the object features. Displacement of the object features over a predetermined number of frames is used to calculate the crossing speed of the object relative to the background features.

Title
Detecting target movement
Application Number
7/799969
Publication Number
5194908
Application Date
November 29, 1991
Publication Date
March 16, 1993
Inventor
Mark Wardell
Nepean
CA
James H Lougheed
Kinburn
CA
Agent
Thomas Adams
Assignee
Computing Devices Canada
CA
IPC
G01P 3/36
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