Patent ID: 8761535

Claim:
A computer-implemented method of enhancing the background of an original document image, comprising: detecting the background color of the original document image by finding a pixel value corresponding to a peak in a histogram of the original document image; determining the desired enhanced background color of the original document image from a background pixel value P b that is in the center of the background color range; determining the factors F l and F r as follows: F l = { β if ⁢ ⁢ P b ≥ T ghigh α Otherwise ⁢ ⁢ F r = { α if ⁢ ⁢ P b ≤ T glow β Otherwise where values α and β are decided based on experimental values and where T ghigh and T glow are high and low pixel thresholds, respectively, and said factors F l and F r define a range to distinguish the background pixel value P b from a foreground pixel value; and enhancing pixels of the original document image in said range to the desired enhanced background color.