It seems they were working on it for a long time: a new PC protection system based on the recognition of a drawing made by user. In other words, instead of typing the classical alphanumeric password at the computer start, user could choice any picture and literally draw above it up to three sketches to unlock the computer.
For example, you could select a family picture and save a straight line going from a face to another, or a circle around a face, or three short dots above a certain detail, and so on. The exact reproduction of the sketch or of the combinations of sketches over the picture, will unlock the PC. Very ingenious and above all comfortable for all tablet and touch PC users.
The patent, which exact title is “Sketch-based password authentication”, took the number 8,024,775 and has been granted by the U.S. Patent Office on September 20th 2011 upon request filed by Microsoft Corporation on Febraury 20th 2008. The new technology will be embedded on Windows 8, still in beta testing.
On the description of the patent, that includes 16 claims, Microsoft explains that the method extracts a template edge orientation pattern from an initial sketch of the user and an input edge orientation pattern from an input sketch of the user, compares the similarity between the two edge orientation patterns, and makes an authentication decision based on the similarity (and not on the exact match of the drawings, as specified by Microsoft).
Wonderful invention. Now, do we have to wait for any Patent Troll?
From this link an image of Microsoft Picture Password (source: slashgear):
http://cdn.slashgear.com/wp-content/uploads/2011/09/picturepassword-580×2561.png
