Automatic zone monitoring

• US 6,816,186 B2
• Filed: 01/18/2000
• Issued: 11/09/2004
• Est. Priority Date: 07/31/1999
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Walter, Andrew Gordon Neil, Sharp, Christopher Edward, Luke, James Steven
• Primary Examiner(s): Vo, Tung T.
• Application Number:
  US09/484,096
• Publication Number:
  US 20030020808A1
• Time in Patent Office: 1,757 Days
• Field of Search: H04/N.718, 348/143, 348/144, 348/145-159, 348/160, 348/169, 348/170, 382/107, 382/219, 345/473, 345/952, 364/188
• US Class Current: 348/159
• CPC Class Codes: G06T 7/20 Analysis of motion motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51

Abstract

A monitoring system using two or more cameras to monitor a space in 3 dimensions is disclosed. One or more virtual 3-D monitored volumes relating to dangerous or restricted areas, are constructed, preferably as CSG objects, within this space. By detecting an object moving within the view of the cameras, the system can determine if a moving object intersects any monitored volumes and take appropriate action.

Claims

1. An automatic zone monitoring system comprising:

means for capturing live video substantially simultaneously from a plurality of video cameras; and

processing means connected to said video cameras comprising;

means for automatically identifying moving objects within a field of view of at least two of said video cameras;

means for defining one or more three-dimensional monitored volumes; and

means for detecting an intersection between said moving objects and the one or more monitored volumes.

2. An automatic zone monitoring system according to claim 1 wherein said defining means comprises means for defining a plurality of monitored boundaries within the field of view of two or more of said video cameras, and means for relating monitored boundaries associated with the same monitored volume, said monitored volume being the intersection of respective pyramids projected through related monitored boundaries from the viewpoint of a camera associated with said monitored boundary.

3. An automatic zone monitoring system according to claim 2 wherein said identifying means comprises means for defining a boundary around said objects moving within the field of view of said video cameras;

and said detecting means comprises means for detecting the intersection of said moving object boundaries and any monitored boundaries defined for said video cameras.

4. An automatic zone monitoring system according to claim 3 comprising warning means responsive to moving object boundaries intersecting at least two related monitored boundaries to raise an alarm.

5. An automatic zone monitoring system according to claim 1 wherein said processing means comprises:

means for generating a correlation between the respective fields of view of said video cameras with the 3-dimensional coordinates of the zone being monitored; and

wherein

said defining means comprises means for defining the one or more monitored volumes in terms of said 3-dimensional coordinates;

said identifying means comprises means for defining a boundary around said objects moving within the field of view of said video cameras; and

said detecting means comprises means for defining respective moving pyramids projected through moving object boundaries from the viewpoint of a camera associated with said boundary in terms of said 3-dimensional coordinates; and

means for generating the intersection of the one or more monitored volumes with the intersection of said moving pyramids.

6. An automatic zone monitoring system as claimed in claim 5 wherein said detecting means comprises means for tracking the intersection of respective moving pyramids and means for relating moving pyramids associated with the same moving object according to the track of the intersection of said moving pyramids, said generating means being adapted to generate an intersection of the set of intersections of related moving pyramids and the one or more monitored volumes.

7. An automatic zone monitoring system according to claim 6 comprising warning means responsive to said intersection being non-null to raise an alarm.

8. An automatic zone monitoring system as claimed in claim 7 comprising means for associating attributes with each moving object, said warning means being responsive to the attributes of a moving object within said intersection to determine the type of alarm to be raised.

9. An automatic zone monitoring system as claimed in claim 1 wherein at least two of said cameras are placed in transverse alignment.

10. An automatic zone monitoring system as claimed in claim 1 wherein at least two of said cameras are placed on planes non-aligned with said moving objects.

11. An automatic zone monitoring system as claimed in claim 1 comprising display means connected to said processor means, said processor means being adapted to display live video from said video cameras, and to superimpose on said respective live video displays, said monitored volumes.

12. A method of automatically monitoring a zone comprising the steps of:

capturing live video substantially simultaneously from a plurality of video cameras;

automatically identifying moving objects within a field of view of at least two of said video cameras;

defining one or more three-dimensional monitored volumes; and

detecting an intersection between said moving objects and the one or more monitored volumes.

13. A computer program product comprising computer program code stored on a computer readable storage medium for, when executed on a computing device, automatically monitoring a zone, the program code comprising means for performing the steps of claim 12.