METHOD FOR IMAGE ENHANCEMENT BASED ON HISTOGRAM MODIFICATION AND SPECIFICATION

Abstract

This invention provides a method for image enhancement based on histogram modification and specification, which comprises the following steps, calculating a first cumulative distribution function for a gray levels of a first image; calculating a first transforming function by the first distribution function and a second distribution function; providing a second transforming function by a first equation or a second equation; providing the second transforming function, the second transforming function is close to the first transforming function; providing the second transforming function, the second transforming function is smooth low-pass filtering result of the first transforming function; and outputting a second image from the second transforming function.