[Medtec] imageContrast.m

%% Bildkontrast
% 3.
function contrast = imageContrast(image)
    % 3.a)
    image = image(:);

    % 3.b)
    image = double(image);

    % 3.c)
    meanGreyValue = sum(image) / numel(image);

    % 3.d)
    contrast = sum(image .* image) / numel(image);
    contrast = contrast - (meanGreyValue * meanGreyValue);
end