Installing posture parameter auto extracting method of imaging device, and monitoring system using the imaging device

• US 6,898,298 B1
• Filed: 07/11/2000
• Issued: 05/24/2005
• Est. Priority Date: 09/08/1999
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Edanami, Takafumi
• Primary Examiner(s): Boudreau, Leo
• Assistant Examiner(s): LU, TOM Y
• Application Number:
  US09/614,142
• Time in Patent Office: 1,778 Days
• Field of Search: 382/104, 382/103, 382/933, 340/436, 340/903, 340/937, 348/118
• US Class Current: 382/104
• CPC Class Codes: G06T 7/80 Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration

Abstract

A monitoring system using an imaging device like a TV camera, etc. enhances a monitoring accuracy without involving manual operations and increasing costs for installing the monitoring system. Two lengths of linear components parallel to each other are extracted from data of an image taken by the imaging device. A rotational angle and an elevation angle of the imaging device are calculated from a positional relationship between those two lengths of linear components and a view point of the imaging device. Obtained is a ratio of a line-to-line distance between the two lengths of linear components when transforming coordinates of the two lengths of linear components on an image plane into coordinates on an imaginary plane to a line-to-line distance between the two lengths of linear components in a real space. A height of position from the plane for installing the imaging device is obtained from this ratio.

Claims

1. An installing posture parameter auto extracting method of an imaging device, comprising:

automatically extracting two lengths of linear components parallel to each other from data of an image taken by said imaging device;

extracting parameters indicating an installing posture of said imaging device on the basis of the two lengths of linear components;

transforming coordinates of the two lengths of linear components on a screen into coordinates on an imaginary plane in a real space;

calculating a distance between the two lengths of linear components on the imaginary plane; and

calculating a height of said imaging device on the basis of a ratio of the distance between the two lengths of linear components on the imaginary plane to an actual distance of the two lengths of linear components.

2. An installing posture parameter auto extracting method of an imaging device according to claim 1, further comprising:

calculating an installing angle of said imaging device in a horizontal direction and an installing angle thereof in a vertical direction from a positional relationship between a central point on a screen of said imaging device, a varnishing point at which the two lengths of linear components intersect each other and a view point of said imaging device.

3. An installing posture parameter auto extracting method of an imaging device according to claim 2, further comprising:

extracting an angle made in the horizontal direction by a straight line passing through the central point and the view point and by a straight line passing through the varnishing point and the view point, as an installation angle of said imaging device in the horizontal direction; and

extracting an angle made in the vertical direction by the straight line passing through the central point and the viewpoint and by the straight line passing through the varnishing point and the view point, as an installation angle of said imaging device in the vertical direction.

4. A method of extracting installing posture parameters of an imaging device in a monitoring system for detecting attributes of a monitoring target object on the basis of an image taken by said imaging device, comprising:

automatically extracting two lengths of linear components parallel to each other from data of the image taken by said imaging device;

calculating the parameters indicating an installing posture of said imaging device on the basis of the two lengths of linear components;

transforming coordinates of the two lengths of linear components on a screen into coordinates on an imaginary plane in a real space;

calculating a distance between the two lengths of linear components on the imaginary plane;

calculating a height said imaging device on the basis of a ratio of the distance between the two lengths of linear components on the imaginary plane to an actual distance of the two lengths of linear components; and

converting attribute data of the monitoring target object on an image plane into attribute data adapted to a real space by using the installing posture parameters.

5. A monitoring system, using an imaging device, for detecting attributes of a monitoring target object on the basis of an image taken by said imaging device, comprising:

a posture parameter calculating unit for automatically extracting two lengths of linear components parallel to each other from data of the image taken by said imaging device, and calculating the posture parameters of said imaging device on the basis of the two lengths of linear components;

a coordinate transforming unit for transforming coordinates of the two lengths of linear components on a screen into coordinates on an imaginary plane in a real space;

a distance calculating unit for calculating a distance between the two lengths of linear components on the imaginary plane;

a height calculating unit for calculating a height of said imaging device on the basis of a ratio of the distance between the two lengths of linear components on the imaginary plane to an actual distance of the two lengths of linear components; and

an attribute data converting unit for converting attribute data of the monitoring target object on an image plane into attribute data adapted to a real space on the basis of the posture parameters.

6. A monitoring system using an imaging device according to claim 5, wherein the attribute data are data indicating a position or a size of the monitoring target object, and

said attribute data converting unit converts the position or the size of the monitoring target object on the image plane into a position or a size in a real space in accordance with the posture parameters.

7. A monitoring system using an imaging device according to claim 5, wherein the attribute data are data indicating a moving speed of the monitoring target object, and

said attribute data converting unit converts the moving speed of the monitoring target object on the image plane into a moving speed of the monitoring target object in the real space in accordance with the posture parameters.

8. A recording medium stored with a program for making a processing device execute:

automatically extracting two lengths of linear components parallel to each other from data of an image taken by an imaging device;

extracting parameters indicating an installing posture of said imaging device on the basis of the two lengths of linear components;

transforming coordinates of the two lengths of linear components on a screen into coordinates on an imaginary plane in a real space;

calculating a distance between the two lengths of linear components on the imaginary plane; and

calculating a height of said imaging device on the basis of a ratio of the distance between the two lengths of linear components on the imaginary plane to an actual distance of the two lengths of linear components.