From http://technology.newscientist.com/article.ns?id=dn14407&print=true

Invention: Smart specs for the blind
12:00 28 July 2008 
NewScientist.com news service 
Justin Mullins 
Electronic canes for the blind are designed to detect nearby objects and
provide a stereo audio signal that informs a person of the location of
obstacles. But they do not distinguish between stationary and moving
objects.

A pair of spectacles fitted with a camera and accelerometers that detect
movement can, however. They are connected to a computer that spots any
obstacles in the field of view and works out which are moving.

The specs provide audio signals to the wearer to let them know what's
happening around them, and which objects are moving, so they can
navigate without bumps. The system was dreamed up by electronics company
Philips.

Read the full smart specs for the blind patent application.