Patent ID: 8224086
Filing Date: 2012-07-17
Classification: H04N

Abstract:
1. A non-transitory computer readable storage medium storing computer program instructions which when executed by a data processing system cause said system to perform a method to transform an electronic image, the method comprising: determining a plurality of averages of a color channel over a plurality of regions inside the image, each region corresponding to a continuous portion of two dimensional space having a plurality of pixels of the image and wherein each of the plurality of averages excludes one or more first pixels which are one of: substantially white or substantially black; determining a target color for the color channel, wherein the target color is gray; scaling color signals of the color channel for each pixel, in a second set of pixels, of the image according to the plurality of averages and the target color, wherein the plurality of averages comprises at least one of an average for a center portion of the image, an average for a surrounding portion of the image and an average for the image; adjusting luminance levels of pixels of the image to stretch a range of luminance levels of the pixels to a predetermined range; and decreasing luminance levels for pixels in a boundary region of the image according to distances of the pixels in the boundary region to a selected point in the image.