公开(公告)号：US20240169577A1

公开(公告)日：2024-05-23

申请号：US18550904

申请日：2022-03-10

Applicant: PROPHESEE

Inventor： Camilo VEJARANO ,  Thomas ROUCH

IPC: G06T7/62 ,  G06T7/13 ,  G06V10/25 ,  G06V10/74 ,  G06V20/40

CPC classification number: G06T7/62 ,  G06T7/13 ,  G06V10/25 ,  G06V10/761 ,  G06V20/44

Abstract: A method for measuring attributes of a particle in motion comprises observing a region of interest with an event-based sensor oriented such that lines of a pixel array of the sensor lie across an expected trajectory of the particle (P) through the region of interest; defining two reference lines of pixels (R1, R2) separated by a spatial distance (D); sampling a first group of events produced by a first of the two reference lines; sampling a second group of events produced by the second of the two reference lines; determining a temporal distance (T) between the second and first groups of events; and providing a longitudinal speed factor (vy) of the particle based on the spatial distance and the temporal distance. The particles have a size spanning multiple adjacent pixels in a line, and the method further comprises analyzing one of the first and second groups of events over multiple time steps in order to produce an outline of the particle in space-time coordinates (x, t) including spatial components based on positions of event-triggered pixels in the lines and temporal components based on the time steps; and converting the space-time coordinates of the outline to spatial coordinates (x′, y′) by multiplying the time steps (t) of the space-time coordinates by the longitudinal speed factor (vy).