When it comes to complex masking, you won't find anything more powerful than Corel KnockOut 2. Built as a plug-in for Adobe® Photoshop®, Corel PHOTO-PAINT® and Corel® Painter™, it lets you retain the finest image details, including hair, smoke, liquid, fire, glass and shadows. And it does it with more speed and accuracy than any other masking technique.
It is very good software.