Security Technology Executive

SEP-OCT 2018

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www. • September/October 2018 • SECURIT Y TECHNOLOGY E XECUTIVE 37 location, sensor status and dynamic views of current security events. A user can view the graphical user interface (GUI) and quickly gain an understanding of the current state of events. This is in comparison to the more traditional systems, where a user, or multiple users, may have to check many monitors to understand the status of various sensors. This improvement in ease of use becomes increasingly important as the ability to hire and maintain secu- rity personnel becomes more difficult due to budget pressures and as the number of sensors in a security system increases. This advantage of situational awareness is much the same as the use of a map when driving to a new location versus the use of a textual description of the same route. Although both have value, the map provides a frame of reference, instant visual cues and quickly communicates a large amount of detailed information. In this same manner, a geospatial user interface quickly conveys important situation infor- mation including physical location details, sensor locations, sensor coverage information, sensor type, target location, target track, target identification, tar- get speed and detailed alarm information. Geospatial Sensors Key components of a geospatial surveillance system are the actual sensors that provide the detection and monitoring of data. When thinking about geospatial sensors, ones that understand inputs and outputs in terms of real space and time, there are several obvious ones that come to mind including radars, LIDARs and GPS sensors. These sensors provide a large amount of data including time-based location, speed and even acceleration. A less obvious group of geospatial sensors are smartphones. It is typically understood that they contain a GPS, but they are often overlooked from a security standpoint. Smartphones in the hands of first responders can be a basis for coordinating assets to an event, as well as, using the smart phone's cam- era capabilities to provide location-based images of events that can be documented and shared within the context of the geospatial surveillance system. There are still other sensors that are "partially geo- spatial" or can be enabled to be geospatial. Fence and in-ground intrusion systems can provide an exact linear position along the fence, or at a mini- mum, identify a specific "zone" where the intrusion occurred. Cameras also fall into this category. Out of the box, they are not a geospatial sensor, but they can be enabled with this capability through a process called "geo-referencing." This process involves a map- ping between the camera field of view and a terrain map, allowing the camera to understand where each video pixel exists in latitude, longitude and elevation. Depending on the scene, just a few video-map pixel pairs are required for the software to extrapolate the mapping for the entire scene. This is true for both fixed cameras and pan-tilt-zoom cameras - even as they move away from the original scene. A geospatially-enabled camera essentially acts as a short-range visual radar. Once a camera understands where a specific pixel resides in real space, it now has the ability to identify an object's real size and real speed. Combining that with visual information, such as aspect ratio, compactness, color and texture, cameras can now classify objects in categories, such as, animal, person, car, truck, boat, aircraft, etc. Still, other sensors can be considered "pseudo- geospatial." These include sensors which have a physical location that has meaning to the security or operations manager. This would include sensors like access control systems, where the location of a specific door or gate has value. Other sensors that fall into this category are proximity sensors, RFID and safety sensors, such as equipment over heat, water detection or fire sensor. Map-Based Sensor Control In addition to being able to display sensor location, sensor state and target information on a map-based GUI, a geospatial system also provides for user interaction through this same interface. This means sensors can be queried and controlled by interac- tion with the map based display. Sensors typically used for event interrogation: PTZ cameras, laser Geo-referenced cameras understand where each video pixel exists in real space. This allows for computation of real object size, regardless of number of pixels on target. In this case, the human comprises fewer pixels, but the system understands its real size as compared to the dog.

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