Patent ID: 8666151
Filing Date: 2014-03-04
Classification: G06T,H04N

Abstract:
1. A method for enhancing the visibility of color images, the method comprising: calculating a histogram of a number of pixels for luminance values of input images and calculating a cumulative distribution function of the number of pixels from a minimum value of the luminance values by using the histogram; determining the luminance values corresponding to the number of pixels according to a previously set ratio to have small luminance values in the luminance value cumulative distribution function as a threshold level for determining baseband signals and determining the pixels having the luminance values smaller than the threshold level to be baseband signal pixels; generating luminance compensation values to apply lower-level luminance compensation values as the pixels have higher-level luminance values, for the pixels having luminance values larger than the threshold level; determining a luminance gain applied to the luminance compensation values according to mean luminance values of the input images and the level of the luminance values of the pixels to which the luminance compensation values are applied; and generating the images with the enhanced luminance values by multiplying the luminance compensation values by the gain and summing the luminance compensation values multiplied by the gain with the luminance values of the input images.