1. A method, comprising: receiving input data representing a) a field of view of a traffic detection zone at a roadway intersection and defining at least a portion of a safe passage zone for vulnerable roadway users at the roadway intersection, and b) traffic signal timing information for the roadway intersection that includes an allotted time for crossing the roadway intersection, the allotted time defined by one or both of a total pedestrian signal crossing time and a start time of a pedestrian signal indicating safe passage for a pedestrian at the roadway intersection; analyzing the input data within a computing environment in one or more hardware and software components executed in conjunction with at least one specifically-configured processor, the one or more hardware and software components configured to perform data processing functions to determine a state of the pedestrian's presence in the field of view, by: analyzing a plurality of pixels in the field of view to identify the safe passage zone, wherein a left edge and a right edge of the field of view define at least a portion of the safe passage zone, measuring pedestrian movement through the safe passage zone, by continually tracking pedestrian position as the pedestrian moves through the field of view, and continually estimating a current pedestrian speed as the pedestrian moves through the field of view, determining a distance to the end of the safe passage zone from the pedestrian position, and dividing the distance to end of the safe passage zone by the current pedestrian speed to calculate an estimated pedestrian time of arrival at the end of the safe passage zone, comparing the estimated pedestrian time of arrival at the end of the safe passage zone with an estimated time remaining for the pedestrian signal determined from the allotted time for crossing the traffic intersection, to predict a pedestrian's ability to cross the safe passage zone within the allotted time; and generating, as output data, one or more instructions to a traffic signal controller in response to the state of the pedestrian's presence in the field of view.