1. A method comprising: projecting modulated light onto an occupant from a plurality of light sources outside of a vehicle; receiving reflections of the light sources at a plurality of detectors having different views and located outside of the vehicle, the vehicle moving relative to the light sources and the detectors; determining three-dimensional data based on a time-of-flight of the reflections; and detecting the occupant using the three-dimensional data comprising combining the outputs of the plurality of detectors to correlate occupant detection data.