Most security folks would agree that deploying reliable automated video systems in the outdoors has been challenging, at best. Generally speaking, video analytics have worked well in controlled environments, such as those in the static indoors. Outdoor security applications are a different story.

Challenges notwithstanding, it is possible to deploy intelligent video surveillance cameras in the outdoors that maintain a high probability of target detection while also addressing the core issue of nuisance alarms. The critical first step  is to focus on image processing in advance of the video content analysis. Such processing resources – often encompassing several digital signal processors (DSPs) –make it possible to analyze the full visual detail of every video frame — inside the camera, at the network edge. In this way, intelligent cameras have the horsepower to clean up the problems associated with the outdoors.

This includes electronically stabilizing the image for camera motion, adapting to changing lighting, fog, rain, snow and sandstorms, and filtering variables such as small animals, blowing debris, trees moving in the breeze and reflections from water.

With such complexity in the outdoors it’s not possible for automated video cameras to accurately determine legitimate targets unless they bring a high degree of image processing to the network edge. When video processing and analysis is performed by video encoders separate from the camera — or by servers in the datacenter — they perform their analysis on a small fraction of the available scene information, at times less than one percent due to preparing data for transmission. Analyzing 100% of the raw scene data directly in the camera as it leaves the imager greatly improves the probability that cameras will accurately detect targets and filter the outdoor impediments that would otherwise trigger nuisance alarms.

Without on-board image processing of sufficient power, the only way to prevent excessive nuisance alarms outdoors is to lower the sensitivity of the system, directly impacting camera range and detection accuracy.

There’s been great disappointment among customers in cases where video intrusion detection systems have been deployed that are not designed to address the outdoor challenges. Substantial on-board image processing in advance of the video analysis is a foundational step, upon which a range of capabilities can be built. These include georegistration of targets, dynamic lighting correction, electronic image stabilization, automatic PTZ steering, and other important security functions. Greater image processing also translates into cost savings through the extended range and such processing affords.

We’ll discuss these additional technologies in subsequent articles. Subscribe to the SightLogix blog and keep updated when they’re published.

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