OpenG has a little toolkit that allow change of brightness and contrast of an image. It might not be sufficient for what you want to do, but that could get you started
http://www.openg.org/tiki/tiki-index.php?page=Image%20Processing PJM
OpenG has a little toolkit that allow change of brightness and contrast of an image. It might not be sufficient for what you want to do, but that could get you started
http://www.openg.org/tiki/tiki-index.php?page=Image%20Processing PJM