11/04/2009

Video Security Tips

By Michael Fickes

What you should know about video surveillance before talking to a consultant

Cameras form the heart of video surveillance. Unfortunately, consultants and security technology integrators don’t always recommend quality cameras and camera systems. Sometimes, their goal is just to have lots of cameras. “Too often, people throw cameras at the job without taking time to evaluate needs,” says Ron Lander, principal and owner of Norco, CA-based Ultrasafe Security Specialists and chair of the ASIS International: Information Technology Security Council.

But cameras alone won’t do the job. Lander points to the case of Jennifer Kesse, a 24-year-old financial analyst who disappeared from her condo in Orlando, FL, in January 2006. She is still missing. Among the clues to her disappearance is a grainy, black-and-white video surveillance tape that shows someone who the police call a “person of interest.”

The video security camera, which was atop an apartment complex, captured someone abandoning Jennifer’s car. But you can’t identify the person, and the grainy, black-and-white video images provide little detail. Worse, the camera system only recorded and stored one frame every 3 seconds. The image of the person of interest shows up in a 6-second clip with just two frames of video. Iron bars from the fence that surrounds the parking lot obscure the person’s face in both frames.

Full-motion video runs at 30 frames per second (fps), which is often difficult to store and transfer digitally because the files are very large. Integrators typically cut back on the frame rate to keep the file sizes manageable. Lander recommends no less than 7.5 to 10 fps. “If a clip from one of my security cameras ever goes on the 11 p.m. news, I want it to be clear,” he says. “It’s also important to make sure your integrator means frames per second when he or she uses the term ‘fps.’ Sometimes the term is used to mean fields per second. One frame equals two fields; 10 fields per second is just 5 frames per second – too slow.”

Defining Quality
It takes a number of integrated components to build a quality video surveillance system. First, you’ll need high-quality cameras selected for specific jobs. Generally, Lander foregoes low-light cameras for full-light models, which require plenty of light. “Color provides the detail you need during the day,” he says. “I also think you should buy cameras that will switch from color to black and white at night. Black-and-white video is crisper and more detailed at night.”

Full-light cameras need lighting that mimics daylight. While lighting at daylight levels when it’s dark outside can be expensive, Lander recommends pricing LED lighting, which is as bright as day, inexpensive, and long lasting.

Today, you can choose from three basic cameras.

  1. Traditional analog cameras come in color and black and white. Limitations include expensive cabling systems that may have to be installed. Another limitation with analog cameras is is low-light environments. Some analog cameras are equipped to switch to black and white at night, which helps.
  2. In some situations, where scenes cannot be lit, infrared cameras can fill in for conventional video cameras. Infrared cameras require their own infrared light sources.
  3. Increasingly popular today are Internet Protocol (IP) cameras. These color or black-and-white digital cameras can connect to existing IT network cabling. Lander prefers the added security of connecting cameras to a separate dedicated security network. “I encourage clients to run a parallel IP network,” he says. “Then the video runs through a separate system and doesn’t fall under the company’s IT bandwidth restrictions if you have to run cable. But, in newer buildings, the cable is often already there. All you need to do is connect the cameras.”

Lander equips many cameras with varifocal lenses that allow scenes to be fine-tuned. Varifocals come in sizes of 3 mm to 8 mm, 8 mm to 12 mm, and 12 mm to 20 mm. “A fixed lens might be too wide or too tight to see what you want,” he says. “By selecting a lens you can adjust, you can get it right.”

Lander also recommends integrating video surveillance systems with video analytics. Studies show that security officers who monitor video surveillance systems typically lose concentration after the first 20 to 30 minutes. “Video analytics has become affordable in recent years,” he says. “It enables the system – the technology itself – to monitor the video.”

Users can tailor analytics to look for the types of events they want to investigate: an abandoned package, a car or person in a secure area after hours, people running, and other activities that should be checked. You can request analytics that will scan for as many as 24 different events.

Finally, you should use signs to tell people about the surveillance system – but be careful about how you word them. Don’t use signs that say, “This video surveillance system is being monitored constantly.” A sign like this raises expectations and makes people think security officers will see a mugging and rush in to help. A security team would certainly try to help, but these incidents are over quickly – usually before help can arrive. Instead of making promises on a sign, use a sign that says, “Video surveillance in use.”

 

Michael Fickes is a freelance writer and owner of Fickes & Co. Inc., a Baltimore publishing firm with experience in the security industry.