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    %% Specify Gamma when Adjusting Contrast
% This example shows how to specify gamma when adjusting contrast with the
% imadjust function. By default, imadjust uses a gamma value of 1, which
% means that it uses a linear mapping between intensity values in the
% original image and the output image. A gamma value less than 1 weights
% the mapping toward higher (brighter) output values. A gamma value of more
% than 1 weights output values toward lower (darker) output values.
%%
% Read an image into the workspace. This example reads an indexed image
% and then converts it into a grayscale image.
[X,map] = imread('forest.tif');
I = ind2gray(X,map);
%%
% Adjust the contrast, specifying a gamma value of less than 1 (0.5).
% Notice that in the call to |imadjust|, the example specifies the data
% ranges of the input and output images as empty matrices.
% When you specify an empty matrix, |imadjust| uses the default range of
% [0,1]. In the example, both ranges are left empty. This means that gamma
% correction is applied without any other adjustment of the data.
J = imadjust(I,[],[],0.5);
%%
% Display the original image with the contrast-adjusted image.
imshowpair(I,J,'montage')