Video performance for high security applications

The complexity of physical protection systems has increased to address modern threats to national security and emerging commercial technologies. A key element of modern physical protection systems is the data presented to the human operator used for rapid determination of the cause of an alarm, whether false (e.g., caused by an animal, debris, etc.) or real (e.g., a human adversary). Alarm assessment (the human validation of a sensor alarm) primarily relies on imaging technologies and video systems. Developing measures of effectiveness (MOE) that drive the design or evaluation of a video system or technology becomes a challenge, given the subjectivity of the application (e.g., alarm assessment). Sandia National Laboratories has conducted empirical analysis using field test data and mathematical models such as binomial distribution and Johnson target transfer functions to develop MOEs for video system technologies. Depending on the technology, the task of the security operator and the distance to the target, the Probability of Assessment (P_As) can be determined as a function of a variety of conditions or assumptions. P_As used as an MOE allows the systems engineer to conduct trade studies, make informed design decisions, or evaluate new higher-risk technologies. This paper outlines general video system design trade-offs, discusses ways video can be used to increase system performance, and lists MOEs for video systems used in subjective applications such as alarm assessment.