I was checking out this website of a small cnc mill maker http://www.microproto.com/ and in their application gallery they have a picture of a engraving that someone did of a photo. http://www.microproto.com/image1.htm I use FeatureCam 2.5 and have used a few others but I am not familiar with a program that will do this particular type of engraving. It may be there own program, I emailed and asked them and will let you know if they actually get back to me. Anyways it looks kind of cool and I could think of a few good uses for it.
Thanks
P.S. I am not affiliated with this company in anyway blah blah blah.
Thanks
P.S. I am not affiliated with this company in anyway blah blah blah.