The method is result of several years of research by the team of doc. Daniel Sýkora. Its main objective was to simplify workflow that would allow quick delivery of information about depth into hand drawings. The whole process is based on an optical illusion - bas-relief, used in sculpturing. It retains relative relationships in the depth of the image that are substantial for the human eye but does not require to preserve proportions in direction parallel with observer´s eyes.
Among other things, the GridCut algorithm, world´s fastest algorithm to find minimum graph cut, is used for the computational process. This algorithm has been developed by doc. Sýkora´s team as well and has recieved US patent. Thanks to the method, fast response times can be achieved, allowing artists to deliver depth to hand drawings interactively.
More information about Ink-and-Ray method can be found here.