Security Technology Executive

MAY-JUN 2015

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May/June 2015 • SECURITY TECHNOLOGY EXECUTIVE 21 www.SecurityInfoWatch.com which enable it to deliver the following: • An 8-megapixel resolution that enables secu- rity professionals to achieve more pixels on target with wider fields of view • A broader palette to render colors more accu- rately so that security is better able to discern the true hue of clothing, vehicles and other objects in the field of view • A frame rate of 30 frames per second (FPS) so security won't miss crucial details in action sequences that are essential for complete situ- ational awareness • A 16:9 aspect ratio so security can achieve a broader coverage of the scene or turn the aspect ratio into corridor view (9:16) to moni- tor activity in long hallways Megapixel cameras, on the other hand, are not bound by standards. And without standards, megapixel cameras often fall short on the other aspects of Image Usability. So which technology will ultimately be able to go the distance? Let's have them duke it out in the Image Usability ring and you can judge for yourself. Round 1: Does Megapixel Win points on Resolution? 4K maxes out at eight million pixels, which appears to be the only punch megapixel can land since megapixel can scale well beyond that range. But is that really an advantage? As mentioned earlier, the operational require- ment of a scene is defined by detecting, recog- nizing, and/or identifying a person or object within the scene. It is generally accepted in the security industry that 80 pixels across the width of a person's face provides sufficient cov- erage for a positive identification. The value of increasing the resolution is two-fold: you can maintain pixel density on the target area and you can use a wider angle lens to cover a broader area. In essence each camera can cover a wider field of view. In theory, this means that security practitioners can deploy fewer cameras to cover the same area while maintaining the operational requirement. So megapixel might have a longer reach when it comes to resolution. But truly, how often does a need arise for more than 8 million pix- els? In my opinion, this lack of installation opportunity makes megapixel a knockout in niche situations only. Round 2: Does 4K Score a Knock-Down with Color Fidelity? Have you ever seen video on a display that just didn't look the same as it did with the naked eye? Color rendition is not always easy for cameras to reproduce accurately. With security, the color of a car or an article of clothing has real forensic sig- nificance. It's one thing if the Baltimore Ravens uniforms appear black instead of deep purple but entirely different if the wrong suspect is appre- hended for the same color disparity. With a broader palette to work from, 4K cameras generate images that accurately depict the tonal values of people, objects, and back- grounds in a scene. Paired with correspond- ing 4K television displays, the color rendition provides accurate representation in both real- time and post-incident forensic review. Speaking of displays, if the display's resolu- tion does not exceed or meet the resolution of the camera then what have you really gained? Most cable networks b r o a d c a s t b o t h H D and standard definition versions of the same programming. Try switching back and forth the next time you are watching your favorite sport and look at the crowd versus the athletes. Are you missing some details? Of course you are. The same thing happens when you view higher resolution surveillance images on displays that don't match the camera's resolution. With something as important as color rendi- tion, 4K wins this round handedly. Round 3: Does 4K Land a Flurry of Jabs for Situational Awareness? A big factor contributing to situational aware- ness is the number of frame per second that a camera is able to deliver. The eye perceives full motion video at around 16 FPS but most secu- rity cameras can deliver 30 FPS. In fact, the HDTV standard defines a minimum frame rate of 30 FPS. And here's where 4K's speed dazzles its opponent. Imagine reviewing a recording of an employee caught stealing money out of a cash register drawer. If you watched that event unfold at five versus 30 FPS, you could be missing a lot of the action. Most likely the thief walked away with an additional $20 in their pocket and you did not have any objective forensic evidence to While people often think of the two technologies as interchangeable, they are not. B y J a m e s M arc ella

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