If your intention is to recolor only parts of a sprite, while leaving other parts colored as they were (like skin, hair) try this:
Draw the colorable parts in sprite images as shades of pure grey (r = g = b), make the image a memblock and convert rgb values that are equal to just r or g or b. You can even make more complex conversions for other colors.
This method also works for textures. It's not fast but not terribly slow if done correctly. Its best done during a load sequence. Animating this effect every screen update (must be faster) would probably require a shader. Or if the sprite is animated with its own frames, you could apply this effect to each frame.
For people who need a more advanced technique.
