Patent Document ID: 5416518
Application ID: 07937053
Patent Status: 1

Claim One:
1. A method for automatically adjusting the focus of a camera on an image frame, comprising the steps of: (a) scanning an image frame; (b) searching for at least one highly bright object in said image frame, said searching step comprising: (1) generating a first count signal by comparing a first reference signal to a luminance signal corresponding to said image frame; (2) generating a second count signal by comparing a second reference signal to said luminance signal, such that said second reference signal is greater in intensity than said first reference signal; (3) determining a ratio of said second count signal to said first count signal, such that, if the ratio of the second count signal to the first count signal is greater than a first threshold, then a highly bright object is detected; (c) searching the image frame for at least one normal object and adjusting the focus of said camera on said at least one normal object when a highly bright object is not detected; (d) adjusting the focus of said camera when a highly bright object is detected in accordance With the steps of: (1) searching for at least one normal object; and (2) adjusting the focus of said camera while masking off said highly bright object if said at least one normal object is detected, said masking off step comprising the steps of: comparing said first reference signal to said luminance signal corresponding to said image frame; generating a comparator pulse signal if said luminance signal intensity is greater than said reference signal. intensity, such that said comparator pulse signal overlaps a portion of said luminance signal corresponding to said highly bright object; generating a first evaluation function by masking said highly bright object from said luminance signal with said comparator pulse signal; (e) adjusting the focus of said camera when a highly bright object is detected and a normal object is not detected by not masking off said highly bright object from said image frame such that said first count signal is at or close to a relative minimum value.