Workshop Questions

There were a lot of questions asked after the workshop. These are the ones
multiple people asked.

Did you make the Phantograms displayed at the NSA using this technique?
  Yes. However most of my Phantograms are made using a program that
  implements a projective transform algorithm.

Can I get the program?
  No. It uses some graphics libraries that I do not own redistribution rights for.
  At some point I will either obtain those rights or use different routines and then
  I will make it available as shareware.

Do you sell Phantograms?
  No. This is just a hobby for me and the legal situation is too confused anyway.

Can I use something other then PhotoShop to make them?
  Of course! The process consists of cropping left and right images down to a
  set size, the size of the target, then doing a perspective correction followed by
  setting the image to the target size. Many programs can do this.

What about the patents?
  I'm not a lawyer so I can't advise you. Patent law is very complex and it can be
  expensive and time consuming to figure out what a patent actually covers.

How do you print Phantograms?
  I use an Epson 2200 on mat paper. Gloss paper does not work as well. You can
  use the same techniques you  would use with any other anaglyph image.

Do you know how people make them using Bryce?
  Yes. It's the method I refer to as "dual projector" and is based on using virtual
   cameras and projectors or "gels" in a 3D graphics program like Bryce.

Is there relevant information in other fields?
  You can find a lot of good information on techniques and technology for removing
  camera lens and perspective distortion on sites dedicated to computer vision,
  surveying and photometric systems. All a Phantogram is is an image that has had
  the distortions created by the camera removed.