Gallerie Selective Color

I saw this Cow man sculture in front of a gallerie.

Many photo editors easily do selective color. I have used Apple's Aperture 3 photo editing and management system.

In Aperture 3, pull up the Inspector HUD and using the Enhance brick, move the Saturation slider all the way to the left so it reads 0.0. This totally desaturates the color.

Then, click on the Enhance brick's gear menu and select 'Brush Enhance away'. Using the brush,you can now selectively remove any of the desaturated area in the image and color reappears. I like Aperture. It meets most of my needs.