CLAHE 代码

Matlab编写的CLAHE，非常值得借鉴。

function [Hist] = clipHistogram（HistNrBinsClipLimitNrXNrY）
%  This function performs clipping of the histogram and redistribution of bins.
%  The histogram is clipped and the number of excess pixels is counted. Afterwards
%  the excess pixels are equally redistributed across the whole histogram （providing
%  the bin count is smaller than the cliplimit）.

for i = 1:NrX
    for j = 1:NrY
        %   Calculate the total number of excess pixels.
        NrExcess = 0;
        for nr = 1:NrBins
            excess=Hist（ijnr） - ClipLimit;
            if excess > 0
                NrExcess = NrExcess + excess;
            end
        end

        %  Clip histogram and redistribute excess pixels in each bin
        binIncr = NrExcess / NrBins;
        upper = ClipLimit - binIncr;
        for nr = 1:NrBins
            if Hist（ijnr） > ClipLimit
                Hist（ijnr） = ClipLimit;
            else
                if Hist（ijnr） > upper
                    NrExcess = NrExcess + upper - Hist（ijnr）;
                    Hist（ijnr） = ClipLimit;
                else
                    NrExcess = NrExcess - binIncr;
                    Hist（ijnr） = Hist（ijnr） + binIncr;
                end
            end
        end
        
        if NrExcess > 0
            stepSize = max（1fix（1+NrExcess/NrBins））;
            for nr = 1:NrBins
                NrExcess = NrExcess - stepSize;
                Hist（ijnr） = Hist（ijnr） + stepSize;
                if NrExcess < 1
                    break;
                end
            end
        end
        
    end
end

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     文件     2406781  2010-04-27 01:56  CLAHE\Contrast_limited_adaptive_histogram_equalization-JoDI-1998.pdf
     文件         516  2008-11-19 18:26  CLAHE\mapHistogram.m
     文件         369  2008-11-19 23:31  CLAHE\makeLUT.m
     文件        1637  2008-11-06 19:36  CLAHE\clipHistogram.m
     文件        3346  2010-04-27 03:58  CLAHE\runCLAHE.m
     文件        3346  2010-04-27 04:27  CLAHE\runCLAHE.m~
     文件        1122  2008-11-20 00:22  CLAHE\interpolate.m
     文件         653  2008-11-19 23:50  CLAHE\makeHistogram.m