Application of industrial cameras in the transportation industry
There are roughly four methods for industrial cameras to detect vehicles. The principle of sampling point detection is to select a matrix-shaped sampling point in a certain part of the lane. When the vehicle passes, the gray value of the sampling point is different from the original road surface. The subtracted statistical value exceeds a certain threshold, indicating the presence of vehicles; detection line detection is to lay a virtual detection line composed of pixels in the vertical or parallel direction of the traffic flow to facilitate the separation of the road surface and the pixel depth of the detection line. When a vehicle passes the detection line, the gray value on the line is different from that when no vehicle passes; if the difference in gray value is greater than a certain threshold, it means that a vehicle passes. These two detection methods are usually used for a single road segment where the vehicle travels. For complex road sections, how to arrange sampling points or detection lines will become a difficulty. In addition to the two, fullscreen detection is a vehicle detection method that employs fullscreen processing. This detection method can obtain more information, but the amount of data to be processed also increases significantly. Night-time vehicle detection is a detection method that is specialized for nighttime and darker lighting environments.
In consecutive images, the recording of the vehicle's trajectory is called tracking. Vehicle tracking methods under industrial camera applications mainly include pattern-based tracking, area-based tracking and contour-based tracking.