Patent ID: 8290209

Claim:
A mobile object recognizing device comprising; an image-taking unit that is mounted on a vehicle and takes images in time series; a feature point extracting means extracting a feature point of each image taken in time series by the image-taking unit; an optical flow creating unit that creates optical flows corresponding to a vector formed by connecting one feature point in one image with another feature point in another image, the connected two feature points being identified to have the same pattern by comparing the feature points with one another between different images; and a grouping means selecting and grouping the optical flows created by the optical flow creating unit which belong to a particular mobile object, wherein each of the selected optical flows is defined as having an extended line intersecting at one focus of expansion within a predetermined error range, and having an equal external ratio of each line segment connecting one of the end points of the optical flow and the focus of expansion within a predetermined error range when the other one of the end points of the optical flow is an externally dividing point on the extended line.