Hosted by Sandra Tsing Loh, The Loh Down on Science is a fun way to get your daily dose of science plus a dash of humor in less than two minutes.
Hosted by Sandra Tsing Loh
Airs Weekdays 2:31, 3:31 and 5:49 a.m.

The Shadow Knows

A new technique can identify individuals using only their shadow.

Who knows what darkness lurks in the hearts of men?

This is Sandra Tsing Loh with the Loh Down on Science

And if you said, "The Shadow" you're old! Like me! And don't WE rock?

Anyway-- Gait observation--watching the way you walk-- is sometimes used to spot suspected felons or missing persons.

Gait analysis techniques generally track folks from the side--not always easy in a crowd.

Overhead surveillance, of the head and shoulders, is easier. But identifying targets is trickier, because people look pretty much the same from above.

Our shadows, though? Very different.

Adrian Stoica of the Jet Propulsion Laboratory has come up with a way to use those shadowy differences to I.D. people from overhead. He calls it "Shadow Biometrics."

In Stoica's technique, cameras track a subject, and measure their shadow and its movements. The data are analyzed to determine the individual's height, build, and unique way of walking, which can help nail down identity.

Stoica says that with today's high-res satellite imagery, the technique can be accurate even from space.

Who knows WHAT darkness lurks in the hearts of men? Well, Adrian Stoica with Shadow Biometrics. TM.