Patent ID: 8908038
Filing Date: 2014-12-09
Classification: G06K

Abstract:
1. A vehicle detection device comprising: imaging circuitry configured to capture two different polarized images from two differently polarized light beams reflected within an imaging area of the vehicle detection device, the imaging area containing a road surface; polarization difference calculation circuitry configured to divide each of the two polarized images captured by the imaging circuitry into a plurality of predetermined identification processing areas and calculate a degree of polarization difference indicating a ratio of a luminance difference between the two polarized images to a total luminance thereof for each of the plurality of predetermined identification processing areas; and vehicle area detection circuitry configured to conduct a vehicle area detection process of detecting a vehicle area in the imaging area by matching a stored vehicle characteristic amount pattern with at least one of the predetermined identification processing areas, by using luminance values associated with light reflected from a vehicle window wherein the polarization difference calculation circuitry generates a polarization difference image based on the degree of polarization difference, wherein each pixel in the polarization difference image is assigned a value of “1” based on whether an associated polarization difference exceeds a predetermined threshold, and areas of pixels that are assigned values of “1” are clustered into a single high polarization difference area, a road surface area, including the road surface, is specified based on dispersion of pixel values in the single high polarization difference area, and the vehicle area is detected upon excluding the road surface area.