wolffd@0: function g = rgb2grayKPM(rgb)
wolffd@0: % function g = rgb2grayKPM(rgb)
wolffd@0: % rgb2grayKPM Like the built-in function, but if r is already gray, does not cause an error
wolffd@0: 
wolffd@0: [nr nc ncolors] = size(rgb);
wolffd@0: if ncolors > 1
wolffd@0:   g = rgb2gray(rgb);
wolffd@0: else
wolffd@0:   g = rgb;
wolffd@0: end
wolffd@0: