San Francisco International Airport (SFO) is a
hub for business travelers, vacationers, immigrants, stopover passengers, on-site workers—and a whole lot of suspicious-looking
people. That's why it's not surprising to discover that the airport operates an extensive
video surveillance system. What is surprising
is how very smart the system is.
When it comes to video surveillance, people tend to
imagine banks of sharp-eyed human observers endlessly
scanning video screens for anything out of the ordinary.
But that's not necessarily true anymore. Sophisticated video
analysis technologies are rapidly replacing people as ever-vigilant sentinels.
"If you have a security guard looking at a monitor, he's
probably going to look at it for 10, 20 minutes and then get bored and zone out," says Dilip Sarangan, a security analyst
for Frost and Sullivan, a technology market research firm. "A
computer never gets bored, and nothing goes unchecked."
By studying human behavior and automatically detecting
the presence and absence of various objects in real time, intelligent video analysis promises enhanced security at an overall
lower cost. "It's more of a proactive rather than a reactive
approach to video surveillance," says T. Jeff Vining, a security
industry analyst at Gartner, another technology research firm.
Government agencies and other organizations are scooping
up intelligent video analysis products at an accelerating pace.
Over a dozen firms now offer some form of the technology.
The vendor pool includes companies like Vidient, Westec
Interactive, and Visual Defence, all of which offer products
that can survey a local area—indoors or outdoors—and spot
anything out of the ordinary.
Intelligent video system sales are projected to grow from
$60 million in 2005 to $400 million in 2012, Sarangan predicts. "It's heading into the business mainstream," he says.
SCANNING SFO
More than 32 million passengers pass
through San Francisco International Airport each year. Visually
studying even a small percentage of this flood of humanity for
quirks and behavior that might betray a sinister motive would
require an army of human observers glued to video monitors.
For a solution that would prove effective without financially
crippling manpower costs, SFO turned to SmartCatch, an intelligent video analysis technology offered by Vidient.
SmartCatch works in conjunction with the airport's existing closed-circuit television (CCTV) systems to detect aberrant or suspicious behavior and distinguish those patterns of
activity from normal activities (). When the behavior-based software spots an anomaly, it sends a video clip via a
pager, laptop, cell phone, or other communications device to
a responder, who can then investigate the situation.
"When we say ‘behavior,' we don't mean facial recognition
or license plate reading. We're really talking about a combination of human and object behaviors," says Steve Goldberg,
Vidient's CEO. In other words, the system looks for people
and objects, such as suitcases or packages, that aren't in the
right place or have lingered in a place for too long.
"So if you parked your car at the curb, where it's only supposed to be for dropoff, and the car doesn't move, it will
alert security," says Michael McCarron, SFO's community
affairs director. The system also can spot "human tailgating,"
when two people pass through a secure door on a single ID
card swipe, as well as things like crowd formation and people
going through an exit lane the wrong way.
Vidient's Windows-based technology is based on sophisticated video algorithms developed over three years by NEC's computer vision engineers. "The algorithms are generally based on
adaptive filtering or adaptive processing—neural network types
that have been used in other data and voice applications," says
Goldberg. SmartCatch detects suspicious situations with an
accuracy rate between 95% and 98%, Goldberg notes.
Like most other intelligent video analysis technologies,
Vidient's product functions by seeing each image as a mosaic
of pixels. The algorithms then work to make sense out of the
mosaic's movement, or lack of movement, and to separate
the pixel cluster from background clutter. "Basically, video
analytics is all software," Sarangan says.