clear all

X = imread( 'pollen.jpg' );
whos
[Y,T] = histeq(X,256);
T = T*255;
image( X )
colormap( gray ( 256 ) )
axis image

imagesc( Y )
colormap( gray ( 256 ) )
axis image
imhist(X)
imhist(Y)
plot(T,'LineWidth',3)
axis([0 255 0 255])