Evaluation of Video Detection Systems Volume 4 - Effects of Adverse Weather Conditions in the Performance of Video Detection Systems

摘要

The performance of three video detection systems (VDS): Iteris, Autoscope, and Peek, was evaluatedusing a side-by-side installation at a signalized intersection under various adverse weather conditions includingrain and snow in both day and nighttime, and light fog and dense fog in daytime. Four types of detection errors(false, missed, stuck-on, and dropped calls) were quantified at stop bar and advance detection zones, and allerrors were visually verified using video images from the intersection. Results indicate that VDS performancewas not greatly impacted under daytime light fog or rain conditions without wind, but significant changes wereobserved under dense fog and snow in daytime, and snow and rain in nighttime. During dense fog conditionsIteris and Autoscope changed their operating mode and placed constant calls due to image contrast loss, withpotential for significant effects on traffic operation, while Peek significantly increased its missed calls. Snow indaytime and nighttime greatly increased false calls for the three systems (more than 50% of the VDS calls werefalse), but it had limited effects on missed, stuck-on, and dropped calls. False calls during rainy conditionswithout wind also increased, during both daytime (around 10%) and nighttime (between 10% and 50%), mostlydue to the reflection of headlights of vehicles in the adjacent lanes. Detailed performance of the three VDS ineach of the three stop bars and the three advance zones, as well as potential causes and effects of the mostprominent error types are presented.