Make the most of bandwidth in IP video surveillance

Jesus Garzón, director for Southern Europe of the manufacturer of high-resolution network-based video systems, Mobotix AG, discusses in this article the benefits of using IP cameras with integrated PCs to improve the efficiency and costs of security systems.

PCs are used, Increasingly, in conjunction with video management software for recordings with IP video surveillance cameras. Despite being an effective combination, centralization of this process creates a "bottleneck" that significantly increases the load on network bandwidth. Today, this problem can already be avoided, using "smart" IP camcorder systems with PCs integrated inside, reducing the required bandwidth to virtually zero. With this system, In addition, there is no limit to the number of built-in cameras with the possibility of connecting to the network.

Instead of analog video cables, cameras that emit images over the network use the standard TCP/IP protocol for transmission. Like this, allow the process to be more economical, because you don't need to use special analog cables (you can turn to any network technology: Wlan, Dsl, Isdn, GSM and Ethernet). Also, and because these devices don't require compliance with rigid analog video standards, restrictions to date on the extent or resolution of images are also removed.

In the case of next-generation IP video surveillance cameras, it's a license-free web technology, because with them you can use the browser available in the operating system of any PC. Such a system, In addition, offers a much higher level of security than that provided by the analog video cable that can be electromagnetically disturbed. An additional advantage is that the use of the TCP/IP protocol for these devices allows unlimited scalability: it is possible to work with hundreds of PCs, connected through a network, keeping your data on the company's servers that require the service.

Hundreds of cameras can also work in exactly the same way. This type of network structure is easy to expand, Using, if necessary, WLAN technology instead of cables.

Not just live

Companies that base their security systems on video surveillance cameras, should keep in mind that live monitoring is not enough to carry out video surveillance tasks effectively. When cameras are used to visualize situations that do not require constant attention, the scenes are also recorded and stored. In order to reduce the costs of this storage and optimize the search for events in the recorded material, many systems on the market only record the sequences in which changes are observed, incorporating motion detection sensors.

To store all important scenes and avoid unnecessary recordings, motion detection is required, where video sensors play an important role. Due to the need to document the scene prior to the event or incident (pre-alarm), the recording system also has to be equipped with a circular buffer capable of storing a few seconds of video.

Centralized management issues

Centralized PCs-based recording has two disadvantages when motion detection and recording footage occur in the pre-alarm buffer:

• Reliable motion detection recording is extremely heavy (Intense), limiting the number of cameras that can be monitored at the same time.
• Motion detection and maintenance of the pre-alarm buffer requires images to be constantly read, which creates a significant network load.

To date, these problems were solved by reducing the size of the image, resolution or quality before events occurred, in order to reduce network load. Once achieved, and after the event took place, image quality and frame size increased to their normal levels. This solution, However, far from optimal.: high image quality is important for reliable motion detection and, In addition, in applications that demand alarm activation, the image quality of the pre-alarm should not be lower.

The solution to reduce network load and eliminate system limitations is simple: move functionality to detect motion and the circular pre-alarm buffer, from PC to camera itself. In the age of high-performance microcomputers and low cost per megabyte of memory, there's no better formula for saving space.

A PC on camera

Incorporating the entire computer's ability to detect scene changes and record them to a pre-alarm buffer inside the camera has also made it possible for the system to organize its own long-term storage. In other words, the camera can autonomously manage your disk storage that has been allocated to you for a PC or server on the network. Combined with large server installations and RAID storage based on standard and inexpensive IT components, there is almost no limitation on storage capacity and reliability.

As a result,, in most applications you no longer need central software for recording, reviewing or scanning stored information to look for possible events.

If only recordings are required, additional video management systems are, In fact, Expendable. If an incident occurs, all it takes to visualize what's happening is a browser. Specialized management systems enable you to gain benefits, However, if the target is in other functions besides storage: control and management of users and groups; neglect; reports of intrusions, assaults and fires or other advanced features, such as searching for events by criteria or integrating different platforms (Analog, digital and intelligent systems).

The advantages of decentralized management

Video recording with IP cameras with integrated PCs offers a compendium of advantages to consider: there are no system limitations in terms of the number of cameras; the video system can expand easily if needed; the answer is extremely quick, because intelligence is built on camera; the workload is very low (is generated only during storage operations); offers a robust system architecture thanks to the lack of a central control system; uses standard IT components to transmit and store images.

Jesus Garzón

Director for Southern Europe Mobotix AG

 

 

 

 

 

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