More and more surveillance video equipment is using the Internet protocol for communication. To date, IP communications has gained the greatest acceptance in centralised devices, such as digital video recorders. But increasingly, devices located at the network edge, including video cameras, have IP communications capability. Other examples are video encoders that add IP capability to analog cameras.

Although IP cameras and encoders represent a relatively small percentage of the total video camera market today, the situation is changing due to technology advances that are enabling new capabilities and bringing costs more in line with the analog market. There are new advances and IP technologies are making an impact on system design and economics.

Nowadays, in general, the more cameras an installation requires, the more likely designers will specify IP cameras. The reason is that the network video recorders (NVR’s) that store video from IP devices generally can handle a greater amount of cameras than traditional digital video recorders (DVR’s) that are designed for use with analog cameras. Even though IP cameras generally cost more than their analog counterparts, the overall system cost may be lower because fewer recording devices are involved.

Traditionally, video analytics were handled through centralised processing but several manufacturers have introduced IP cameras or encoders that can provide some video analytic capabilities - and where feasible, it should be the preferred option. The reason relates to the MPEG4 compression standard, which because it conserves bandwidth and minimizes storage requirements and with the H.264 compression, this has even greater advantages across both network bandwidth requirements and storage.

Several technology advances have paved the way for analytics at the edge. The early days of analytics was very processor-intensive — you needed a very powerful computer to run the algorithm. More recently, digital signal processors have enough horsepower to run most algorithms, and some algorithms that started with a server solution are now running on edge devices.

IP Efficiencies

There are almost no limitations as to where a network video product can be placed. IP network video has the capacity to provide a high level of integration with other equipment and functions, making it a continually developing system. A fully integrated IP network video system can be used for a multitude of applications simultaneously: for instance, access control, building management, point-of-sales systems, ATMs, as well as fire, intruder and visitor management.

Scalability and Flexibility

An IP network video system can be expanded by adding more network cameras. You can choose exactly what you need today, and scale the system at any time to meet your growing needs. New technologies, additional cameras, and extra storage capacity can all be easily added as required, thanks to strict adherence to industry standards.

Edge Storage

Another capability that is moving from a centralised location to the network edge is storage. Here, too, advances in technology have made this possible, where it would not have been in the past.

A video camera equipped with a secure digital high-capacity card, also known as an SD card, can store a couple of days worth of video recorded at 30 frames per second, Nilsson explains. In the event that greater recording time is needed, some video cameras have a connection for a hard drive or other external storage unit.

Another option is to back up the local recording by transmitting video at a lower frame rate to a centralised storage device. Although that video will be of lower quality, the advantage is that much less bandwidth would be required than if the central storage device were recording at full frame rate — and higher-quality images still will be available on the edge device. Reducing network traffic through local storage may be particularly valuable when a costly wide area network connection is involved.

Video Management

Some video installations, especially those with a large number of cameras, call for a video management system to simplify the process of retrieving or analysing video images. When an installation includes video management and local storage, SensorTec Security is very selective proposing equipment that will work well together.

Other Trends

While analytics and storage are the most talked-about trends driving intelligence toward the edge of the video network, several others are also worth noting. Some IP cameras can accept input and outputs from external sensors. That capability lets the sensors trigger recording — or higher-frame rate recording — under certain conditions, such as when a sensor reveals that the room temperature has reached a pre-set limit.

Another new capability found in some IP cameras is two-way audio. Although eavesdropping laws make audio recording impractical in some parts of the world, pre-recorded audio warnings are useful deterrents that can be triggered in response to motion detection or another external event.

Virtually all IP cameras and encoders lend themselves to another capability that can simplify video system installation — power over Ethernet (POE) technology, which brings power to a device over the same twisted pair wiring that also carries data in an Ethernet network. With the advent of PoE-compliant devices, networked systems allow edge devices to be easily installed and relocated anywhere on the network.