Intruding-object detection apparatus

• US 20040041905A1
• Filed: 08/27/2003
• Published: 03/04/2004
• Est. Priority Date: 08/30/2002
• Status: Active Grant

• Current Assignee: Subaru Corp.
• Original Assignee: Fuji Jukogyo KK (Subaru Corp.)
• Inventors: Shibayama, Norifumi
• Granted Patent: US 7,260,243 B2
• Time in Patent Office: Days
• US Class Current: 348/47
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• CPC Class Codes: G08B 13/19602 Image analysis to detect motion of the intruder, e.g. by frame subtraction
• CPC Class Codes: G08B 13/19604 involving reference image or background adaptation with time to compensate for changing conditions, e.g. reference image update on detection of light level change
• CPC Class Codes: G08B 13/19641 Multiple cameras having overlapping views on a single scene
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources
• CPC Class Codes: H04N 7/188 Capturing isolated or intermittent images triggered by the occurrence of a predetermined event, e.g. an object reaching a predetermined position signal generation from motion picture films H04N5/253

Abstract

Just after starting, right and left images, each of which includes a fixed object and does not include an intruding object, are read as background images. Background parallaxes are obtained from the background images. Subsequently, when an intruding object exists in the background images, motion pictures of the intruding object which is moving are read. The brightness of an arbitrary pixel in the right image is compared to the brightness of a pixel, deviated from the pixel by the background parallax, in the left image. As the result of the comparison, the image corresponding to the intruding object is cut from the right image. Consequently, the influences of a three-dimensional object existing in the background and an environmental condition are eliminated. The intruding object can be detected with high accuracy and high reliability.

Claims

1. An intruding-object detection apparatus for detecting an object intruding into a field of view as an intruding object using a pair of images taken by a stereo camera, the pair of images being a reference image and a comparison image, the apparatus comprising:

means for obtaining a matching point for the same subject between the reference image and the comparison image and, for storing the obtained matching point; and

means for evaluating the difference between image information near an arbitrary position in the reference image and image information near a position, deviated from the arbitrary position by the stored matching point, in the comparison image and for outputting an area, where the difference is large, as an area indicating an intruding object.

2. The apparatus according to claim 1, wherein the matching point is a parallax for the same subject between the reference image and the comparison image.

3. The apparatus according to claim 1, wherein the matching point is obtained every pixel.

4. The apparatus according to claim 1, wherein the matching point is obtained every block which has a predetermined size and a predetermined shape in the image.

5. The apparatus according to claim 1, wherein the difference between the image information includes the absolute value of the difference between the brightnesses of the images.

6. The apparatus according to claim 1, wherein the difference between the image information is evaluated every pixel.

7. The apparatus according to claim 1, wherein the difference between the image information is evaluated every block which has a predetermined size and a predetermined shape in the image.

8. The apparatus according to claim 1, wherein a process of storing the matching point is executed to the whole image only once before an intruding-object detection process.

9. The apparatus according to claim 1, wherein a process of storing the matching point is sequentially executed to a part of the image simultaneously with an intruding-object detection process to update stored data regarding the matching point at any time.