Why Multi-Sensor Megapixel Cameras Work (Security Today)


Video surveillance technology has come a long way from the days when analog CCTV cameras dominated the market. The best security cameras available today deliver single and multi-sensor HDquality video, or higher, at fast frame rates in varying light conditions with many important built-in features. This is the result of significant advances in key technologies, including image sensors, image processing, video compression, network bandwidth use, data storage, and VMS. Security cameras improve overall surveillance system capabilities and provide other valueadded benefits that expand beyond conventional security applications. An excellent example of this concept in action is the multi-sensor panoramic megapixel camera. Arecont Vision introduced this technology to the market in 2006.

A PTZ camera mounted in a hallway intersection is capable of capturing images down the length of each hall, one hallway at a time. Multiple single-sensor cameras could be deployed, with one camera covering each of the four hallways that intersect.

Only a multi-sensor megapixel camera is capable of viewing all four of the hallways simultaneously while providing outstanding resolution and image quality across each scene. As a result, multi-sensor megapixel cameras provide a higher level of overall situational awareness and security in this and many other deployment examples.

Additionally, multi-sensor technology provides significant operational improvements for surveillance systems. For example, a 180-degree multi-sensor panoramic camera integrates seamlessly in most VMS platforms, which allows operators to easily see and better comprehend. Studies have addressed how many cameras a single operator can view and still be effective. A 180° multi-sensor panoramic camera lines up four fields of view as if it were from a single camera. This allows operators to effectively view significantly more area, increasing overall situational awareness, and it improves the ability of the operator to view multoiople areas of concern or interest.

Here are five of the top reasons why multi-sensor panoramic megapixel cameras are vastly superior to single-sensor fixed or PTZ cameras:

TOTAL COST OF OWNERSHIP (TCO) AND RETURN ON INVESTMENT (ROI)

The appropriate use of multi-sensor megapixel cameras is an extremely cost-efficient solution. Because one single multi-sensor camera can replace multiple singlesensor cameras, systems can usually be designed with fewer cameras to cover the complete area of interest.

Multi-sensor megapixel panoramic cameras can significantly lower the total cost of ownership and generate a higher return on investment by reducing the number of cameras, fewer VMS licenses, lower installation costs, fewer network switches, and less long-term maintenance.

COVERAGE WITH LESS EQUIPMENT

With multi-sensor megapixel cameras, each sensor can be individually adjusted to focus on areas of interest in 180°, 270° or 360° ranges. This design allows one single four-sensor panoramic megapixel camera to provide the same detailed coverage as multiple single-sensor megapixel cameras.

For example, a multi-sensor camera can be configured to provide 270° panoramic coverage using three sensors with 90° lenses, with the fourth image sensor looking straight down. This configuration is ideal for placement on the corner of a building to achieve detailed wide area coverage with a specific focus on the building’s entrance.

A multi-sensor panoramic camera can be deployed at the center of a parking lot to provide 180° coverage of the entire area with excellent image quality. Neither of these example configurations can be supported by a single-sensor camera or a PTZ without loss of coverage and situational awareness.

IMAGE QUALITY

The ability to capture high-resolution images using megapixel video is one of the main benefits of IP-based video systems. The greater amount of information captured in these images supports additional functionality and benefits for system users.

For example, automated real-time intervention and post-incident video investigation are possible with the features found in megapixel cameras, including forensic zooming, the region of interest viewing, image cropping, motion detection, and panoramic views. Multi-sensor panoramic megapixel cameras virtually eliminate the need for PTZ cameras in most environments. With multiple sensors capable of operating independently of one another, multi-sensor megapixel cameras increase the capability and value of megapixel video fourfold.

SITUATIONAL AWARENESS

A vital element of security is real-time awareness of an environment. This is critical to identify a developing or active incident and understand how best to respond. While all surveillance video provides some situational awareness, multi-sensor megapixel cameras have several advantages.

First, by providing a constant video feed from every direction, multi-sensor megapixel cameras ensure that there is never a moment when the camera is pointed in the wrong direction. Next, the high resolution delivered by megapixel imagers enables viewers to zoom in to the recorded image to view extreme detail. Finally, the same high resolution makes it possible to clearly see events and individuals even at great distances. Together these factors significantly improve situational awareness for multi-sensor megapixel camera users.

VARYING AND LOW LIGHT LIGHTING SITUATIONS

Two of the most important criteria for surveillance cameras is their ability to produce usable images in dimly lit environments and adapt to changing lighting conditions 24/7 within a scene while maintaining high-quality video streaming. For example, a camera monitoring a parking lot is subject to constantly changing illumination levels during the course of the day. Adding to the challenge is the fact that the scene may be subject to a wide range of varying light levels within different areas of a single scene caused by headlights, shadows or adjacent buildings. Most cameras fail to provide adequate image quality in these lighting conditions due to inferior processing and control capabilities. However, there are advanced new imaging solutions that overcome these longstanding lighting issues:

Wide dynamic range (WDR) technology provides a dynamic range of 100dB at full resolution without lowering frame rates. By combining long and short exposures in the same field of view, WDR maximizes the amount of detail in both bright and dark areas of a scene. The WDR performance of Arecont Vision cameras represents up to 50dB improvement (300X) in dynamic range compared to conventional cameras.

Pixel binning provides users with maximized image usability in low light applications by combining a cluster of pixels into a single pixel. This technology increases the surface area and the amount of light that hits each pixel, vastly improving the signal-to-noise ratio to increase low light sensitivity.

Low-light technology, such as Arecont Vision’s STELLAR increases low-light performance by reducing motion blur, noise, and storage requirements while also enhancing contrast and allowing color imaging in near-complete darkness.

Arecont Vision offers a variety of multi-sensor megapixel cameras that incorporate some combination of all of these innovations in various configurations to satisfy virtually any application where challenging lighting conditions exist.

Multi-sensor panoramic megapixel cameras are the superior choice over single-sensor fixed or PTZ cameras for use in a wide range of installations.

The increased capabilities, higher performance, and lower total cost of ownership these cameras deliver all add up to a winning combination for both integrators and their end-user clients. With the many benefits provided, it is easy to see why multi-sensor panoramic megapixel cameras are so desirable by security professionals today.