%histogram matching

clear

source_img = imread('test.bmp');
[n,m] = size(source_img);
H = imhist(source_img);

L = 2^8;

%cumulative distribution
C = cumsum(H);

C = C/(n*m);

%histogram equalization function
T = round((L-1)*C);

%out_img = uint8(equal_img);
%imshow(out_img);

%histogram matching fuction
PDF = zeros(256, 1);
total=0;
for i=1:L
    PDF(i)= 1-((i-1)/(L-1));
    total=total+PDF(i)
end
PDF=PDF/total;

G = round((L-1)*cumsum(PDF));

for i=1:n
    for j=1:m
    idx=find(G-T(source_img(i,j))>=0,1,'first');
    equal_img(i,j)=idx;
   end
end

out_img = uint8(equal_img);

imshow(out_img)

소스인데요 무슨오류가 생긴건지.. 휴 .. 과제 어렵네요..