Patent ID: 9232121
Filing Date: 2016-01-05
CPC Classification: H04N

Claim Text:
1. A system comprising: a calibration imaging system to capture a plurality of blurred calibration images of a calibration scene, wherein at least one known unusable calibration image sensor array (ISA) element is present at a known location in a calibration ISA associated with the calibration imaging system; a calibration defect detector operatively coupled to the calibration ISA to identify a calibration ISA element as a candidate unusable element if a calibration contrast ratio calculated from an illuminance indicated by the calibration ISA element and an average illuminance indicated by a set of surrounding calibration ISA elements is greater than a calibration threshold contrast value, and the average illuminance indicated by the set of surrounding ISA elements is greater than a calibration threshold illuminance value; a threshold selector coupled to the calibration defect detector to select a combination of the calibration threshold illuminance value and the calibration threshold contrast value such that the at least one known unusable calibration ISA element is reliably identified as unusable and no other calibration ISA elements are identified as unusable; an illuminance controller coupled to the calibration defect detector to iteratively vary an illuminance associated with the calibration scene as ones of the plurality of blurred calibration images are captured; a threshold illuminance iterator coupled to the threshold selector to iteratively vary the calibration threshold illuminance value across a dynamic range of the calibration ISA for each iteration of the average illuminance associated with the calibration scene as the ones of the plurality of blurred calibration images are captured; and a threshold sharpness iterator coupled to the threshold selector to vary the calibration threshold contrast value across the dynamic range of the calibration ISA for each iteration of the calibration threshold illuminance value as the ones of the plurality of blurred calibration images are captured.