Patent ID: 8401290

Claim:
A method for processing a digital image, comprising: storing a digital image that includes a set of pixels; determining a distribution of color values of the set of pixels of the digital image; determining a minimum ink density value associated with the digital image, wherein the minimum ink density value is determined by: analyzing the distribution to identify a first range of color values that are the lightest group of color values in the digital image, analyzing the distribution to identify a second range of color values that are the next-to-lightest group of color values in the digital image, and arriving at the minimum ink density value by analyzing the second range of color values, wherein the analysis of the second range of colors is based on a pixel count associated with an adjacent pair of color values within the second range of colors, and the adjacent pair of color values has a slope that is closest to zero within the second range of color values; determining a darkest color value, wherein the darkest color value is determined by analyzing the distribution to identify the darkest color value with a non-zero pixel count; determining an ink offset based on the darkest color value; and for each pixel of the set of pixels of the digital image: determining if a color value associated with the pixel is darker than the minimum ink density value and, if the color value of the pixel is darker than the minimum ink density, adjusting the color value associated with the pixel by adding the ink offset to the color value, and if the color value of the pixel is not darker than the minimum ink density, setting the color value of the pixel to a background color value.