Automated detection and correction of eye color defects due to flash illumination

Claim 2

The method of claim 1 further including correcting of the defective color in each eye color defect group.

Claim 3

The method of claim 2 wherein the threshold value represents minimum and maximum allowed values consistent with the expected color of a eye color defect group.

Claim 4

The method of claim 1 wherein the group size feature is area, the group shape feature is eccentricity, the coloration and brightness features are hue, saturation, lightness, and red to maximum (green, blue) ratio.

Claim 5

The method of claim 1 wherein the scores per pixel in steps d) and f) are equal to the product of the scores of individual features, and the scores of individual features are weighted functions of the feature values of the pixels.

Claim 6

The method of claim 5 wherein the group score is an average of all the pixels.

Claim 8

The method of claim 7 further including correcting of the defective color in each eye color defect group.

Claim 9

The method of claim 8 wherein the threshold value represents minimum and maximum allowed values consistent with the expected color of a eye color defect group.

Claim 10

The method of claim 7 wherein the group size feature is area, the group shape feature is eccentricity, the coloration and brightness features are hue, saturation, lightness, and red to maximum (green, blue) ratio.

Claim 11

The method of claim 7 wherein the scores per pixel in steps d) and f) are equal to the product of the scores of individual features, and the scores of individual features are weighted functions of the feature values of the pixels.

Claim 12

The method of claim 11 wherein the group score is an average of all the pixels.

Claim 14

The method of claim 13 wherein the threshold value represents minimum and maximum allowed values consistent with the expected color of a eye color defect group.

Claim 15

The method of claim 13 wherein the group size feature is area, the group shape feature is eccentricity, the coloration and brightness features are hue, saturation, lightness, and red to maximum (green, blue) ratio.

Claim 16

The method of claim 13 wherein the scores per pixel in steps d) and f) are equal to the product of the scores of individual features, and the scores of individual features are weighted functions of the feature values of the pixels.

Claim 17

The method of claim 16 wherein the group score is an average of all the pixels.

Claim 18

The method of claim 13 wherein step i) (i) includes determining at a lower resolution a correction factor for each low resolution pixel which is a function of the number of eye color defect pixels at the original resolution disposed at the same image location.

Claim 19

The method of claim 13 wherein step i) (i) includes categorizing at a higher resolution each original eye color defect pixel into eye color defect pixels and non-eye color defect pixels.

Claim 20

The method of claim 13 including desaturating and reducing the illuminance for each body, border, and glint pixel.

Claim 22

The method of claim 21 which includes determining at a lower resolution a scale factor for each low resolution pixel which is a function of the number of eye color defect pixels at the original resolution disposed at the same image location.

Claim 23

The method of claim 21 which includes categorizing at a higher resolution each original eye color defect pixel into eye color defect pixels and non-eye color defect pixels.

Claim 24

Apparatus for detecting for eye color defects of a subject in an image due to flash illumination, comprising the steps of: a) means for scanning an image containing the subject in a medium to produce a digital image; b) means for defining a spatial region within such digital image wherein one or more eye color defects may exist, which region includes at least a portion of the subject's head; c) means for sampling pixels within such spatial region for their color content and comparing each such sampled pixel with a plurality of threshold values which are representative of eye color defects to identify possible eye color defect pixels; d) means for segmenting the identified possible eye color defect pixels into one or more spatially contiguous groups; e) means for calculating a first score for each pixel of each segmented group and for each group based upon a plurality of features including group size, group shape, coloration, and brightness to identify eye color defect group candidates; f) means for selecting a seed pixel based on its score from each identified eye color defect group candidate and determining all the neighboring pixels which are within a predetermined score range of their neighboring pixels and those pixels in a group which represent a significant pixel score transition so that the determined transitions identify the outer boundary of an eye color defect group candidate; g) means for calculating a second score for each pixel for each eye color defect group candidate based on a plurality of features including group size, group shape, coloration, and brightness to determine an eye color defect group; h) means for selecting the best group score of an eye color defect group candidate and comparing it relative to a predetermined threshold group score to determine whether an eye is present and identify the most likely eye; and i) means for determining whether another eye color defect group is present based on whether the area of that eye is within a predetermined threshold ratio of the area of the color defect group corresponding to the most likely eye, and whether this group must be within a predetermined threshold angular subtense of the most likely eye along the predetermined horizontal axis of the subject's head.

Claim 25

Apparatus for detecting and correcting for eye color defects of a subject in an image due to flash illumination, comprising the steps of: a) means for scanning an image containing the subject in a medium to produce a digital image; b) means for defining a spatial region within which one or more eye color defects may exist, which region includes at least a portion of the subject's head; c) means for sampling pixels within such spatial region for their color content and comparing each such sampled pixel with a plurality of threshold values which are representative of eye color defects to identify possible eye color defect pixels; d) means for segmenting the identified possible eye color defect pixels into one or more spatially contiguous groups; e) means for calculating a first score for each pixel of each segmented group and for each group based upon a plurality of features including group size, group shape, coloration, and brightness to identify eye color defect group candidates; f) means for selecting a seed pixel based on its score from each identified eye color defect group candidate and determining all the neighboring pixels which are within a predetermined score range of their neighboring pixels and those pixels in a group which represent a significant pixel score transition so that the determined transitions identify the outer boundary of an eye color defect group candidate; g) means for calculating a second score for each pixel for each eye color defect group candidate based on a plurality of features including group size, group shape, coloration, and brightness to determine an eye color defect group; h) means for selecting the best group score of an eye color defect group candidate and comparing it relative to a predetermined threshold group score to determine whether an eye is present and identify the most likely eye; and i) means for determining whether another eye color defect group is present based on whether the area of that eye is within a predetermined threshold ratio of the area of the color defect group corresponding to the most likely eye, and whether this group must be within a predetermined threshold angular subtense of the most likely eye along the predetermined horizontal axis of the subject's head; j) means for correcting the defective color in each eye color defect group by: (i) determining the correct resolution and whether each pixel at the corrected resolution is an eye color defect pixel; (ii) categorizing the eye color defect pixels at the corrected resolution into either body, border, or glint categories; and (iii) correcting the eye color defect pixels in the body, border, or glint categories.