Bloomberg: More cameras a good thing
01:17 - Source: CNN

Story highlights

New technology makes it easier to identify suspects in surveillance photos and video

The Boston bombing suspects were identified on security-camera footage

Cities such as New York and London now have thousands of cameras on the streets

Facial-recognition software can detect age, gender and even moods

CNN  — 

Even after the identification of the Boston bombing suspects through grainy security-camera images, officials say that blanketing a city in surveillance cameras can create as many problems as it solves.

A network of cameras on city streets and other public spaces increases the chances of capturing a criminal on video but can generate an overwhelming amount of evidence to sift through. The cameras make some people feel more secure, knowing that bad guys are being watched. But privacy advocates and other citizens are uneasy with the idea that Big Brother is monitoring their every public move.

Meanwhile, facial-recognition software and other technologies are making security-camera images more valuable to law enforcement. Now, software can automatically mine surveillance footage for information, such as a specific person’s face, and create a giant searchable database.

After last week’s bombings at the Boston Marathon, authorities had to sift through a mountain of footage from government surveillance cameras, private security cameras and imagery shot by bystanders on smartphones. It took the FBI only three days to release blurry shots of the two suspects, taken by a department store’s cameras.

The FBI last week released security-camera images of suspects in the deadly Boston Marathon bombings.

Compare their quick turnaround with the 2005 London bombings, when it took thousands of investigators weeks to parse the city’s CCTV (closed-circuit television) footage after the attacks. The cameras, software and algorithms have come a long way in eight years.

Cities under surveillance

In major cities, in the age of terrorism, someone is almost always watching.

The cameras used in London are part of the city’s extensive and sophisticated “Ring of Steel” surveillance system that combines nearly a half million cameras, roadblocks and license plate readers to monitor the heart of the city. Set up in 1998, the system is one of the most advanced in the world and allows authorities to track anyone going into or out of central London.

Many residents question the effectiveness of London’s system, however. In 2008, only one crime was solved for every 1,000 cameras, according to the city’s police. CCTV cameras across Britain also cost authorities nearly $800 million over the past four years, according to civil liberties group Big Brother Watch.

Modeled after London’s system, New York’s Lower Manhattan Security Initiative monitors 4,000 security cameras and license plate readers south of Canal Street. The project uses feeds from both private and public security cameras, which are are all monitored 24 hours a day by the NYPD.

Using face and object-detection technology, the police can track cars and people moving through 1.7 square miles in lower Manhattan and even detect unattended packages. The $150 million initiative also includes a number of radiation detectors and automatic roadblocks that can can be used to stop traffic in an emergency.

Boston’s camera network is smaller than those in London and New York, though that is likely to change soon. In 2007, Boston law enforcement had an estimated 55 CCTV cameras set up around the city. Since then, the city has expanded its surveillance system, though authorities there are not commenting on the exact scope of the current camera setup.

Boston’s example has shown the power of these systems to help solve crimes, causing many to call for even more cameras. But it’s still not clear whether they are effective at preventing crimes. According to the Surveillance Studies Centre at Queen’s University in Ontario, urban surveillance systems have not been proven to have any effect on deterring criminals.

Facial recognition

A surveillance camera attached to a building in the Financial District of New York City.

As the volume and quality of cameras and sensors are ramped up, cities are turning to more advanced face- and object-recognition software to makes sense of the data.

“We describe what’s in the video, and we store that in a database,” said Al Shipp, CEO of San Francisco-based 3VR, one of several companies that makes this type of facial-recognition technology.