Minimum Requirements for Taxicab Security Cameras

• 作者: Alfred A. Amendola Bradley H. Newbraugh Darlene Weaver Douglas M. Cantis Harlan E. Amandus Shengke Zeng
• 来源期刊: 交通科技期刊(英文)
• 学科: 医学
• 关键词: Taxicab HOMICIDE FACIAL Identification Photographic RESOLUTION Dynamic Range LENS DISTORTION Motion BLUR
• 年，卷（期）: 2014,（3）
• 页码范围: 216-255
• 页数: 40页
• 分类号: R73

摘要

Problem: The homicide rate of taxicab-industry is 20 times greater than that of all workers. A NIOSH study showed that cities with taxicab-security cameras experienced significant reduction in taxicab driver homicides. Methods: Minimum technical requirements and a standard test protocol for taxicab-security cameras for effective taxicab-facial identification were determined. The study took more than 10,000 photographs of human-face charts in a simulated-taxicab with various photographic resolutions, dynamic ranges, lens-distortions, and motion-blurs in various light and cab-seat conditions. Thirteen volunteer photograph-evaluators evaluated these face photographs and voted for the minimum technical requirements for taxicab-security cameras. Results: Five worst-case scenario photographic image quality thresholds were suggested: the resolution of XGA-format, highlight-dynamic-range of 1 EV, twilight-dynamic-range of 3.3 EV, lens-distortion of 30%, and shutter-speed of 1/30 second. Practical Applications: These minimum requirements will help taxicab regulators and fleets to identify effective taxicab-security cameras, and help taxicabsecurity camera manufacturers to improve the camera facial identification capability.