Traffic monitoring apparatus

• US 6,810,132 B1
• Filed: 11/17/2000
• Issued: 10/26/2004
• Est. Priority Date: 02/04/2000
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Edanami, Takafumi, Umezaki, Yasushi
• Primary Examiner(s): Boudreau, Leo
• Assistant Examiner(s): Miller, Ryan J.
• Application Number:
  US09/714,226
• Time in Patent Office: 1,439 Days
• Field of Search: 382/104, 382/107, 340/435, 340/436, 340/903, 340/907, 348/148, 348/149, 701/117, 701/301
• US Class Current: 382/104
• CPC Class Codes: G06T 7/254 involving subtraction of images
• CPC Class Codes: G06V 20/00 Scenes; Scene-specific elements control of digital cameras H04N23/60
• CPC Class Codes: G06V 20/54 of traffic, e.g. cars on the road, trains or boats
• CPC Class Codes: G08G 1/0116 from roadside infrastructure, e.g. beacons
• CPC Class Codes: G08G 1/04 using optical or ultrasonic detectors
• CPC Class Codes: G08G 1/164 Centralised systems, e.g. external to vehicles
• CPC Class Codes: G08G 1/205 Indicating the location of the monitored vehicles as destination, e.g. accidents, stolen, rental

Abstract

A traffic monitoring apparatus that is used to reliably detect the occurrence of an abnormal situation, such as a traffic accident. An imaging device produces and outputs images of a point to be monitored at predetermined intervals. Image inputting unit of the traffic monitoring apparatus inputs images output from the imaging device. Move vector extracting unit first generates a background image from a plurality of images input, then specifies areas where a moving object exists by calculating the difference between the background image and a newly input image, and then extracts move vectors from the specified areas. Parameter calculating unit calculates the slope and intercept, being parameters, of a move vector by considering the move vector as a segment. Plotting unit plots parameters for each move vector in a two-dimensional coordinate system with slope and intercept as its bases. Abnormality judging unit judges, in the case of the parameters being plotted in an unusual area, that an abnormal situation has occurred and informs a control center etc. (not shown) via a network of this.

Claims

1. A traffic monitoring apparatus for detecting an abnormality in traffic by monitoring images produced by an imaging device, the apparatus comprising:

image inputting means for inputting images produced by the imaging device;

move vector extracting means for extracting a move vector of an object from images input from the image inputting means;

parameter calculating means for calculating parameters in the case of a move vector extracted by the move vector extracting means being considered as a segment;

plotting means for plotting parameters for a segment calculated by the parameter calculating means in a two-dimensional coordinate system with the parameters as its bases; and

abnormality judging means for judging, in the case of the parameters for a segment plotted in an unusual area, that an abnormality has occurred,

wherein the parameter calculating means calculates the slope and intercept, being parameters, of a segment by performing Hough transformation on the move vector.

2. The traffic monitoring apparatus according to claim 1, wherein the abnormality judging means distinguishes a normal situation from an abnormal situation by the distribution of the parameters of a segment calculated at normal time in the two-dimensional coordinate system.

3. The traffic monitoring apparatus according to claim 1, wherein the move vector extracting means extracts a background image from images input from the image inputting means, specifies areas where a moving object exists by calculating the difference between the background image and a newly input image, and extracts move vectors with priority given to the specified areas.

4. The traffic monitoring apparatus according to claim 1, wherein the imaging device includes a wide-angle lens, further comprising correcting means for correcting images produced by the imaging device to usual images.

5. The traffic monitoring apparatus according to claim 1, wherein the imaging device produces infrared images, further comprising infrared projecting means for projecting infrared light on a subject.

6. A traffic monitoring apparatus for detecting an abnormality in traffic by monitoring images produced by an imaging device, the apparatus comprising:

image inputting means for inputting images produced by the imaging device;

move vector extracting means for extracting a move vector of an object from images input from the image inputting means;

position predicting means for predicting a future position of an object by referring to a move vector extracted by the move vector extracting means;

distance calculating means for calculating the distance between a pair of objects randomly selected by referring to the position of an object predicted by the position predicting means; and

judging means for judging, in the case of the distance calculated by the distance calculating means falling below a predetermined threshold, that an abnormality has occurred,

wherein the position predicting means calculates an acceleration vector of an object as well and predicts the future position of the object on the basis of its acceleration vector obtained, move vector, and present position.

7. The traffic monitoring apparatus according to claim 6, further comprising:

parameter calculating means for calculating parameters in the case of a move vector extracted by the move vector extracting means being considered as a segment;

plotting means for plotting parameters for a segment calculated by the parameter calculating means in a two-dimensional coordinate system with the parameters as its bases; and

abnormality judging means for judging, in the case of the parameters for a segment plotted in an unusual area, that an abnormality has occurred,

wherein when the judging means judges that an abnormality has occurred, whether an abnormal situation really has occurred is verified by the parameter calculating means, plotting means, and abnormality judging means.

8. The traffic monitoring apparatus according to claim 6, wherein the move vector extracting means extracts a background image from images input from the image inputting means, specifies areas where a moving object exists by calculating the difference between the background image and a newly input image, and extracts move vectors with priority given to the specified areas.

9. The traffic monitoring apparatus according to claim 6, wherein the imaging device includes a wide-angle lens, further comprising correcting means for correcting images produced by the imaging device to usual images.

10. The traffic monitoring apparatus according to claim 6, wherein the imaging device produces infrared images, further comprising infrared projecting means for projecting infrared light on a subject.