Coloring a grayscale image to two colors

I have a grayscale image as shown below, I would like to color the dark layer to blue color and the white layer to red color and if possible I would like to change the background to any other color. Can anyone help me with this?

Thanks in advance.

Answer 1

[Image Analyst]

Determine the threshold between light and dark and have the colormap have one color up to that threshold and then the other color after that threshold. like

threshold = 128
cmap = repmat([0, 0, 1], 256, 1); % Initialize to blue
% Make red from 128 & brighter
for row = threshold : size(cmap, 1)
	cmap(row, :) = [1,0,0];
end

Make the obvious adaptations for 3 or more color ranges.