Patent ID: 8180561

Claim:
An obstacle detection apparatus comprising: an electronic camera installed on a detection vehicle, the electronic camera configured to capture an image of an external view ahead of said detection vehicle, image processing circuitry configured to process data produced by said camera, expressing said image, for detecting objects which may constitute obstacles located ahead of said detection vehicle, a memory having image parameter information specific to said camera stored therein, communication circuitry configured to perform at least one of two modes of communication, said modes comprising inter-vehicle communication between said detection vehicle and a preceding vehicle and road-to-vehicle communication between said detection vehicle and a roadside apparatus, information generating circuitry configured to derive size dimension information expressing a size dimension of an object detected by said image processing circuitry, as measured in an image plane of said camera; information acquisition circuitry configured to acquire, via said communication circuitry, actual size dimension information expressing an actual size dimension of a specific obstacle located ahead of said detection vehicle; and distance calculation circuitry configured to accurately calculate a value of distance between said specific obstacle and said detection vehicle, based upon said size dimension derived by said information generating circuitry, said actual size dimension, and said image parameter information; wherein said actual size dimension is a distance between a pair of objects which are located on said specific obstacle; said information acquisition circuitry is configured to acquire above-ground height information in conjunction with said actual size dimension information, said above-ground height information expressing an actual height value of said pair of objects above a road surface, said obstacle detection apparatus comprises ground height difference calculation circuitry configured to calculate a ground height difference value as a difference between a height of a road surface on which said detection vehicle is situated and a height of a road surface on which said specific obstacle is situated; and said calculation of said ground height difference being based upon said distance value calculated by said distance calculation circuitry, said above-ground height value obtained by said information acquisition circuitry, and said image parameter information.