Histogram "deequalization" - contrast decrease

Lower contrast of an image using simple math

Other languages:
Ag = rgb2gray(imread('kytka256.jpg'));

subplot(2,2,1);imshow(Ag)
subplot(2,2,2);imhist(Ag)

Dq=(Ag*0.2)+100; % histogram deequalization
subplot(2,2,3);imshow(Dq)
subplot(2,2,4);imhist(Dq)
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