Correcting defect pixels in a digital image
AssigneeHewlett-Packard Development Company, L.P.
InventorsJonathan Yen, Daniel R. Tretter, Truong-Thao Nguyen
Life of this patent
Estimating the term…
Abstract
Systems and methods of correcting one or more defect pixels in a source image are described. The source image is formed from a plurality of pixels each having a respective value. In one scheme, a defect pixel is corrected based upon curvature information computed from pixel values located near the defect pixel. In another scheme, a median pixel value is determined from values of pixels located near a defect pixel, and the defect pixel is corrected based upon the median pixel value.
Claims21
A method of correcting one or more defect pixels in a source image formed from a plurality of pixels each having a respective value, comprising:
- (a) in response to a determination that curvature information is complete, replacing a defect pixel with a value computed from pixel values located near the defect pixel along a direction selected based upon a comparison of curvature values computed along multiple different directions;
- (b) in response to a determination that curvature information is incomplete and gradient information is complete, replacing the defect pixel with a value computed from values of pixels positioned near the defect pixel along a direction selected based upon a comparison of gradient values computed along multiple different directions;
- and
- (c) in response to a determination that curvature information and gradient information are incomplete, replacing the defect pixel with an average of values of non-defect pixels neighboring the defect pixel.
A system, comprising a correction filter configured to:
- (a) in response to a determination that curvature information is complete, replace a defect pixel with a value computed from pixel values located near the defect pixel along a direction selected based upon a comparison of curvature values computed along multiple different directions;
- (b) in response to a determination that curvature information is incomplete and gradient information is complete, replace the defect pixel with a value computed from values of pixels positioned near the defect pixel along a direction selected based upon a comparison of gradient values computed along multiple different directions;
- and
- (c) in response to a determination that curvature information and gradient information are incomplete, replace the defect pixel with an average of values of non-defect pixels neighboring the defect pixel correct a defect pixel.
Dependencies are inferred from the claim text.