Learned a new trick just by tinkering with GIMP 2.6. I adjusted the hue until I came up with a green leaf. You can see a little (very little) change in the surface below the leaf. The reason for so little change in the surface may be because it falls within the grays and there is little color to change. This was a simple process that took less than five minutes. If you are looking for inexpensive (free) image editing software, GIMP 2.6 just might work for you. To see the original picture go to Dolce Pics. You might even give it a go yourself.