Watch Your Step

The video world is awash in new terminology: IP addressable, AI, edge devices, network appliances, latency, 4CIF, MPEG4. What does it all mean? To some of us old salts who used to send our CCTV cameras to a shop to be repaired (back when it was cheaper to have them serviced than to buy a new one), it means familiar terms like coax, lines of resolution, real-time video, and closed circuit are being replaced. It means that the gap between leading edge and bleeding edge has gotten smaller. It means that it's easier to be overwhelmed by technology advances and sales claims, and harder to gauge actual performance between devices. It means the video world is running into the information technology playground.

Most people consider the migration of video from analog to digital a good thing. The future of video is clearly in digital, and digital video recording, storage, distribution and search capabilities are driving the market for digital systems. However, not all digital video systems or features are ready for prime time, and not all are yet better than their analog counterparts. In the eyes of someone who has worked with and experienced the performance of analog video systems, the live video viewing and control capabilities of digital systems leave a lot to be desired. Above all, the communications paths or networks are in many cases not ready to handle the load of video viewing to which many security professionals are accustomed.

 

Limiting Factors

The most limiting aspect of digital video systems today is that they must be designed to function within the bandwidth limitations of the available networks. Analog systems are unencumbered by this limitation, unless you consider the cost of the cable. Bandwidth limitations can cause performance problems, such as latency of the control functions for networked PTZs. Latency is the delay between the time an operator executes a command and the time the field or edge device (in this case a PTZ motor) responds. Analog system latency is hardly detectable on late-model and best-of-breed systems, but the latency in many of today's digital systems can frustrate a security operator following a suspect in a parking lot or on a casino floor. It may be hard to keep up with a person walking at normal speed.

The most limiting factor of analog systems, on the other hand, is that they require a point-to-point wire connection. One hundred cameras would need 100 coax cables run from the edge device to the controller. That is quite a lot of copper or fiber optic glass.

 

A Hybrid Solution

Many security professionals consider hybrid video systems the best solutions today. The hybrid configuration includes a dedicated analog transmission (coax or fiber optic cable) from the video camera to the controller and/or DVR. The analog communication allows high-resolution viewing and high-speed control on the local controller. If the DVR device is then connected to the network with an IP address, the system becomes a hybrid of analog and network digital components.

Security or facility managers traveling on the road can, with appropriate authorization as verified by password controls, tap into the recorder and view live or recorded images. However, bandwidth limitations may still limit the video quality and quantity. The limitations can be in the form of resolution, measured today by Common Intermediate Format (CIF) with values of 1CIF, 2CIF, 3CIF and the highest, 4CIF; or by the number of frames per second (fps) that can be viewed (from single-digit fps to a high of 30 fps). Nonetheless, remote viewing of dubious quality is better to many than no remote viewing at all. Future advances in video systems should provide improvements.

 

Artificial Intelligence Benefits

A major new advantage of digital video systems is the development of what some people call artificial intelligence (AI) capabilities. Some digital video systems go well beyond just recording. Sophisticated new capabilities include the ability to discern motion in a particular direction, detect packages left stationary for a prescribed length of time, detect when the video image has been blocked, count the number of people or vehicles in the video scene, and read vehicle license plates. This leads to video systems performing functions outside security.

To illustrate these design concepts of new digital video systems, I have selected a few project examples.

 

Campus Applications

Schools have increasingly been including security video systems in their facilities. They generally have little live viewing activity; instead, most are interested in recording video for viewing at a later time, usually after the detection of an incident. For local systems, a set of video cameras strategically located within the school and sending analog signals to a local video recorder has traditionally been sufficient. However, some schools have upgraded their DVRs to NVRs and have allowed video signals to be viewed outside the school. Concern about student privacy issues has encouraged many such school districts' law enforcement or security departments to partner with IT to develop encryption and access control configurations that provide adequate security over the video signal.

This type of implementation allows school district or public law enforcement agencies to view video signals from any school in the district. Some school districts have central command centers that monitor the status of systems in all district schools. With remote video, officers can view and control the video signals to determine the status of the facility without having to send an officer to physically perform a tour. There are also law enforcement vehicles equipped with laptops that are capable of viewing the video signals from the schools via wide area radio frequency (Wi-Fi) digital signal communications networks. These officers find it invaluable to be able to see what is happening inside the building before entry or to assist in the appropriate response.

 

Non-Security Functions

Security departments are constantly battling the budget crisis. Some security departments have used video creatively to create joint cost justifications for their systems with other departments.

In one instance, the security department of a certain company could not get management to sign off on a plan to purchase additional cameras for a certain area. To get the buy-in, the department created a plan to use the proposed cameras to count the number of customers in a check-in or check-out line. The customer count information would be used to redirect customers to less dense lines or areas. The data information would be taken from the video system and sent to another server, which would prepare the information for display to customers looking to get through the wait process as quick as possible. The video images provide a useful customer service and throughput tool while also providing security with additional eyes on the target.

 

Law Enforcement WANs

Several major cities are introducing video surveillance to their streets for the use of law enforcement agencies. The signals are being transmitted over Wi-Fi or other WAN systems—impossible without digital signals. These cities have visions of receiving video signals from participating and willing building owners that would assist law enforcement in their response to an alarm condition. The desired outcome is creating a force multiplier in the fight against crime.

 

IP video transitions have produced both success stories and disappointing results. Be careful in considering the video system for your business. The good news is, the security industry can at times be very nimble in bringing new technology to the market. The bad news is, not all new technology is good for everyone right away. IP-addressable cameras were introduced several years ago, but there still are some features on these devices that need to be further developed to meet the standards set by analog controllers. Network IP cameras will still go blank when the network is down. The same concepts hold true for DVRs and NVRs. Yet there are also features and benefits to these systems that may be invaluable to you. Consider the needs of your business and consult with professionals you trust to provide good advice. I will not be going back to tube cameras for our designs, but our designers are not always jumping on the latest innovation until the device is tested and evaluated.

 

 

 

 

Lauris Freidenfelds is a vice president of Sako & Associates Inc., a leading provider of security consulting, design and construction management services. He is based at the company's headquarters in Chicago and can be reached by phone (312-879-7230) or e-mail (lfreidenfelds@rjagroup.com). For more information, visit the Sako & Associates Web site at www.sakosecurity.com.

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