On Wednesday, April 23, 2003, at 04:42 PM, Thomas Shaddack wrote:
Vnity is about as old as mankind. With vanity, various ways come to change one's appearance.
Wider lips. Narrower mouth. Wider eyes. Different shape of eyes. Name a facial feature, there is a way to enhance or suppress it.
Face-recognition systems rely on visual appearance. They typically need edges - edges of mouth, edges of eyes...; one popular algorithm for indexing a face is recognizing these points and measuring their distance. A little amount of properly applied pigment could shift these values by couple percents.
So low-tech device a lipstick is could be a potential tool for lowering the probability of a successful identification by face recognition. Ladies often carry many more similar "terrorist tools" in their purses.
Opinions, comments?
These reasons are largely why ear shape, ear-eye-mouth geometry, etc., have been increasingly used in face recognition schemes. It is very difficult to use makeup to modify fundamental geometries over these scales, and fundamental geometries are easy to do math on (using affine or projective geometry, for example). While a woman may be able to change her eye appearance, her lip shape, or even her eyebrow shape, she cannot easily change the affine geometry of ear-nose-eye-chin. Men cannot do even this, lest they be considered fags, but they can of course change beard characteristics...which is why no face recognitions worth a dime to Big Brother use facial hair (or hair style in general) as a determinant. A friend of mine is doing a lot of work with "support vector machines" as generalization of neural nets, Hopfield networks, and other learning systems. Quite amazing how hard it is to hide from such classifiers. A little bit of makeup just doesn't do it, not when these systems have been trained on hundreds of thousands of exemplars with varying amounts of eye shade, eye liner, lipstick, and facial hair alterations. --Tim May "The whole of the Bill [of Rights] is a declaration of the right of the people at large or considered as individuals... It establishes some rights of the individual as unalienable and which consequently, no majority has a right to deprive them of." -- Albert Gallatin of the New York Historical Society, October 7, 1789