Patent ID: 8203622
Filing Date: 2012-06-19
Classification: H04N

Abstract:
1. A method for correcting image data of a scene by a digital camera, the method comprising the acts of: capturing a first image of the scene corresponding to a first illumination level; capturing a second image of the scene corresponding to a second illumination level, different from the first illumination level and having a resolution that is relatively lower than the first image; determining correction factors, for a non-uniform illumination area of the first image based on image data of the first and second images, wherein the correction factors are determined for one or more representative pixels, wherein the correction factors are determined by the formula: IC[x,y]=Y/X(a[x,y]−b[x,y]), where IC[x,y] is an illumination correction as a function of a position (x,y) within an object field, b[x,y] is an intensity as a function of the position (x,y) of an image data point of interest in an image data set captured at illumination level X, where X is a first artificial illumination level, a[x,y] is an intensity as a function of the position (x,y) of an image data point in an image data set of interest captured at illumination level Y, where Y is a second artificial illumination level, and wherein Y is greater than X; and applying the correction factors to the non-uniform illumination area of the first image to obtain an illumination corrected image, wherein the correction factors are applied to one or more pixels associated with the non-uniform illumination area of the first image based on position of a pixel relative to at least one of the representative pixels.