Companies and institutions of all sizes continue to adopt networked IP video surveillance systems due to a wide variety of benefits, but its ease of integration with other security systems continues to be one of the best reasons to upgrade. Additionally, advanced features and specifications of IP cameras, coupled with assorted compression algorithms, have dramatically enhanced video surveillance solutions by allowing end users to save time and, over time, costs. However, because of a rising amount of networked elements, more strain is imposed upon the network, requiring an organization’s IT department to collaborate with safety and security to achieve a sturdy and robust foundation consisting of best-in-class technology.
One of the most important aspects of an organization’s computer network is the bandwidth capacity, which requires optimization to be able to transmit large quantities of digital video information reliably. The more IP cameras (or other smart devices) on a network, the more bandwidth is required. Managing the bit rate of the video aids transmission and avoids the risk of choking a network, which may have a limited amount of space available. Bit rate reduction can be accomplished by incorporating advanced compression methods into the system, as well as decreasing the amount of images transferred per second.
Bit rate: How much space an image takes up on a network in one second, quantified as “bps”, “bit/s”, or in conjunction with an SI prefix (e.g. “Mbps”, “Mbit/s”)
Another challenge with networked video surveillance is the transmission of unimportant data being digitized/processed, compressed, and transmitted through the network, resulting in excessive bandwidth use and potential network clogs. There are a few ways to combat this:
- Blanking: With regard to pan/tilt/zoom (p/t/z) cameras, specific locations can be preprogrammed into the memory in the event of transitioning the lens’ view from one predetermined location to another, resulting in useless video data during the camera’s movement. Blanking omits the video image from being processed into the network until the new location is obtained.
- Activity detection: Similar to blanking, activity detection relies on motion-activated algorithms embedded within the camera or system that only processes and transmits data over the network when a certain stimulus is detected or threshold is crossed.
- Variable bit rate: For organizations who may require a continuous video feed to be transmitted at all times, the video feed’s bit rate can decrease when there is no activity detected within the scene and increase when there is activity, saving the network’s bandwidth during periods of inactivity
Of course, the overall video surveillance system needs to be expertly designed in order to leverage the underlying network infrastructure. Organizations implementing IP/megapixel cameras must account for higher bandwidth allocation but also consider the number of cameras, when they will operate, images per second transmitted, and compression methods.