Sony’s SNT-V704 encoder has a built-in protocol that allows it to support other manufacturer’s pan-tilt-zoom cameras.

Security technicians know how to improvise: for years you’ve overcome the challenges inherent in making separate, proprietary security systems work as a whole — in other words, systems integration!

During this transitional time in the security industry, as technology progresses from a closed-circuit to a network-based platform, it’s important that transitional products be available that can help you move your customers forward, too. The last thing you may want to do is force your customers to abandon their investment in an already-installed analog video system in order to take advantage of network video equipment’s features.

“Hybrid” video equipment can help you move forward with today’s technology. It allows customers to expand their video system’s size and/or update its functionality. Its specific purpose is to connect analog video surveillance equipment to digital equipment, such as a network video recorder.

“The challenge is: If you already have an existing investment, how do you migrate that into network-based going forward?” asks Allen Chan, senior product manager at Sony’s Security Products Division, Park Ridge, N.J.

There are several reasons for recommending a hybrid approach to customers, Chan describes.

“You have an existing analog-based system and you want to tie in the advantage of network-based products as it relates to functionality,” Chan says. “An analog camera brings the information back to the head-end, but an IP-based [camera] has more of an interactive approach, because IP can bring analytics,” he explains.

Another reason for using hybrid equipment is to be able to expand your customer’s system. Your customer might already have installed analog cameras, and wants to add either network cameras or more analogs with encoding (video server) devices, says Steve Surfaro, group manager, strategic technical liaison, Panasonic Security Systems, Secaucus, N.J. “Both analog input and network-based recording systems are kept and managed from a single digital video management or physical security information management system,” he relates.

Or the system could have been designed intentionally to include both analog and network devices — using network recording technology — and grow accordingly, Surfaro mentions.

“Sometimes, the newer technology the user upgrades to is not available as a network video camera and requires the use of hybrid components like an analog camera and video encoder. An example of this technology is video cameras with extreme sensitivity and those imagers that are used with specialized infrared illumination,” Surfaro says.

Some high-speed pan-tilt-zoom (PTZ) cameras also are only available as analog products, but with hybrid products they can be used in a networked system.

Panasonic’s WJ-NT314 is a multi-channel video encoding device with optional, embedded video analytics and video processing.

Hybrid Choices

Generally, dealers can purchase either individual components or an entire hybrid solution. Surfaro lists some of the products, which Panasonic sells, that may be used commonly in a hybrid installation:
  • Fully digital network cameras with analog outputs;

  • Multi-channel video encoding devices with optional, embedded video analytic and video processing functions;

  • Multi-channel video decoders that support existing analog display devices;

  • Multi-channel video decoders that support the new high-definition display devices (through HDMI direct digital interface);

  • Digital video management software that supports both analog and network-based systems on a common interface.
The purpose of an encoder is to convert an analog video signal into a digital stream, “so the output is pure network,” Chan describes.

There is also the head-end, or recording solution, to consider. Using video encoders with analog cameras allows your customer to take advantage of network recording systems for both expanded size and better quality.

“In a DVR world there are a finite number of inputs to a recorder,” Chan explains. “That limitation is imposed by the video inputs on a machine. The [network-based recorder] has a better ability to scale depending on the performance of the system…there is no physical limitation.

“With a network camera you’re doing the encoding, or changing into a pure digital stream, from the camera to the head end. They’re already dealing in digital data because the recording is already digital. When transmitting analog signals there is degradation. So you’re better off doing that compression at the camera,” Chan says.

Compatibility & Interoperability

If the existing CCTV system is from one manufacturer, must the hybrid products be from the same manufacturer in order for the system to function properly? “Not at all,” Surfaro answers. “There are video encoders and network video recorders that support multiple camera protocols.”

In operation, analog cameras can be operated alongside network cameras in a hybrid set-up. By using video encoders, analog cameras can be recorded on the same network video recorders (NVRs) that network video cameras use, Surfaro explains.

“Analog cameras are easily controlled and their video processed through video encoders; they appear the same as their true digital counterparts to a common digital video management system user interface,” he says.

However, for a PTZ camera, compatibility may be more of a concern. Chan says there is no single protocol for a PTZ; that multiple vendors have different ways of communicating with the product to control the panning, tilting, and zooming functions. Therefore, the encoder that you select must be able to communicate with those protocols.

Finally, you must ensure that at the head-end, the application software supports the hybrid encoders that you’ve chosen.

In any video surveillance system — whether it encompasses all network technology or hybrid technology — bandwith utilization can’t be ignored.

“In the analog domain you have all of these analog cameras coming into the DVR. In a network system it’s more of a shared line, so you need to be aware of your network utilization and what frame rates at what quality you’re streaming,” Chan cautions.

In the end, much of the decision about frame rates and quality comes down to a compromise, because your customer must stay within his storage limitations.