04219847 is referenced by 160 patents and cites 6 patents.

A method of obtaining on-line data useful in determining the center of area or centroid of a geometrical area of unspecified shape lying in a larger x-y scan field and having its existence indicated by a level discriminated amplitude or intensity or a parameter measurable in the z-dimension comprising; scanning the x-y field in a known raster pattern and obtaining a series of discrete output voltage pulses related to elemental x-y points in the scan field and having an amplitude related to the amplitude or intensity of the said parameter; generating a series of discrete clock pulses related to elemental x-y points in the scan field; obtaining a series of x and y synchronizing pulses from and related to the x-y scan field; establishing in relation to the clock pulses and the x and y synchronizing pulses a smaller x-y scan field in the form of a rectangular window around the geometrical area in the larger x-y scan field, the boundaries as x-y co-ordinates of the said window being known; identifying, from the series of discrete clock pulses, those pulses that coincide with pulses obtained above having an amplitude above a preset voltage level and which fall within the boundaries of the smaller x-y scan field such as to define sample point areas in the geometrical area; making an overall count of the number of pulses identified above, making a count of the number of elemental x-y point each of the pulses identified above are spaced from a boundary of the window in both the x and the y directions to provide x-moment arm counts and y-moment arm counts, and summing the x-moment arm counts and the y-moment arm counts, said counts taken with the count obtained from above providing data for computing the center of area or other mathematical functions of the geometrical area.

Title
Method and apparatus of determining the center of area or centroid of a geometrical area of unspecified shape lying in a larger x-y scan field
Application Number
6/14207
Publication Number
4219847
Application Date
February 22, 1979
Publication Date
August 26, 1980
Inventor
Charles I Perratt
Ottawa
CA
Harold F L Pinkney
Ottawa
CA
Agent
J R Hughes
Assignee
Canadian Patents & Development
CA
IPC
H04N 7/18
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