Computers: Detecting heart disease and recognizing faces, they also gauge how you like a movie
Daniel J. McDuff, a graduate student, stood in front of a mirror at the Massachusetts Institute of Technology’s Media Lab. After 20 seconds or so, a figure — 65, the number of times his heart was beating per minute — appeared at the mirror’s bottom. Behind the two-way mirror was a Web camera, which fed images of Mr. McDuff to a computer whose software could track the blood flow in his face.
The software separates the video images into three channels — for the basic colors red, green and blue. Changes to the colors and to movements made by tiny contractions and expansions in blood vessels in the face are, of course, not apparent to the human eye, but the computer can see them.
“Your heart-rate signal is in your face,” said Ming-zher Poh, an M.I.T. graduate student. Other vital signs, including breathing rate, blood-oxygen level and blood pressure, should leave similar color and movement clues.