Methods and apparatus for providing fault tolerance in a surveillance system

• US 20070035627A1
• Filed: 08/11/2005
• Published: 02/15/2007
• Est. Priority Date: 08/11/2005
• Status: Active Grant

• Current Assignee: SightLogix, Inc.
• Original Assignee: SightLogix, Inc.
• Inventors: Chin, Danny, Romanowich, John, Cleary, Geoffrey
• Granted Patent: US 8,471,910 B2
• Time in Patent Office: Days
• US Class Current: 348/159
• CPC Class Codes: G08B 13/19608 Tracking movement of a target, e.g. by detecting an object predefined as a target, using target direction and or velocity to predict its new position
• CPC Class Codes: G08B 13/19643 wherein the cameras play different roles, e.g. different resolution, different camera type, master-slave camera
• CPC Class Codes: G08B 13/19663 Surveillance related processing done local to the camera
• CPC Class Codes: H04N 21/4223 Cameras H04N23/00 takes precedence
• CPC Class Codes: H04N 21/472 End-user interface for requesting content, additional data or services; End-user interface for interacting with content, e.g. for content reservation or setting reminders, for requesting event notification, for manipulating displayed content end-user interfaces for retrieving video data from a database G06F16/739; network services for supporting unicast streaming H04L65/612
• CPC Class Codes: H04N 21/6581 Reference data, e.g. a movie identifier for ordering a movie or a product identifier in a home shopping application
• CPC Class Codes: H04N 21/6587 Control parameters, e.g. trick play commands, viewpoint selection
• CPC Class Codes: H04N 7/17318 Direct or substantially direct transmission and handling of requests
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A coordinated surveillance system uses a larger number of fixed low resolution detection smart camera devices and a smaller number of pan/tilt/zoom controllable high resolution tracking smart camera devices. The set of detection cameras provide overall continuous coverage of the surveillance region, while the tracking cameras provide localized high resolution on demand. Each monitor camera device performs initial detection and determines approximate GPS location of a moving target in its field of view. A control system coordinates detection and tracking camera operation. A selected tracking camera is controlled to focus in on, confirm detection, and track a target. Based on a verified detection, a guard station is alerted and compressed camera video is forwarded to the guard station from the camera(s). The guard station can direct a patrol guard to the target using GPS coordinates and a site map. Redundancy is provided by using multiple control units, each able to handle the full load in the event of failure. Camera devices vote on the status of the control units. A failed detection camera device can be temporarily replaced by a tracking camera device in a back-up mode of operation thus maintaining full overall basic coverage of the surveillance region.

Claims

1. A method of providing fault tolerance in a security system, the method comprising:

providing for at least a plurality of different areas to be monitored, at least one first type camera device for each of the different areas in said plurality;

operating at least one first type camera device to perform a target detection operation to detect the presence of a moving to target in the area being monitored by the particular first type camera device;

using a second type camera device during a normal mode of operation to verify detection of a target by one of said first type camera devices prior to a guard interface unit being notified of the detection of a target by one of said first type camera devices;

monitoring the condition of said first type camera devices to determine proper camera device operation; and

upon detecting a fault condition in a first type camera device, initiating a fault mode of operation including controlling said second type camera device to monitor the area which was being monitored by said first type camera device corresponding to the detected fault condition.

2. The method of claim 1, further comprising:

while operating in said fault mode of operation, in response to the second camera device detecting a target performing the steps of;

generating a target detection signal; and

sending the target detection signal to the guard interface unit without requiring verification by another camera device.

3. The method of claim 2, wherein upon detecting a fault condition in a first type camera device, multiple second type camera devices are assigned to cover the area previously monitored by said first type camera device which had a fault.

4. The method of claim 3, wherein said first type camera devices are fixed mount camera devices and wherein said second type camera devices are movable mount camera devices.

5. The method of claim 1, further comprising:

operating first and second system control units, each of the first and second system control units controlling different sets of camera devices in said system, said first and second system control units each having the ability to take over control of at least some of the camera devices controlled by the other one of the first and second control units in the event of a detected fault of one of the first and second control units.

6. The method of claim 5, further comprising:

operating the first system control unit to monitor for signals from camera devices controlled by said second control unit indicative of a fault condition in said second control unit.

7. The method of claim 6, further comprising:

operating the first system control unit to determine if a fault occurred in the second control unit based on information including a number of camera devices which indicate a fault in said second control unit relative to a number of camera devices which indicate no fault in the second control unit.

8. The method of claim 7, wherein the detection the control unit fault is also a function of a self test performed by second system control unit with the result of the self test being communicated to the first control unit.

9. The method of claim 7, wherein the detection of the control unit fault is also a function of a test performed by first system control unit on the second system control unit via signals transmitted over an interface existing between the first and second control units.

10. The method of claim 2, further comprising:

upon detecting that the faulty first type camera device has been restored to a non-fault condition, reverting to said normal mode of operation.

11. A fault tolerant security system, comprising:

at least one first type camera device for each of a plurality of different areas to be monitored;

at least one of said first type camera devices including a target detection module enabled to perform a target detection operation to detect the presence of a moving to target in the area being monitored by said at least one first type camera device;

a second type camera device; and

a control system using said second type camera device during a normal mode of operation to verify detection of a target by one of said first type camera devices prior to a guard interface unit being notified of the detection of a target by one of said first type camera devices, said control system including;

i) a camera monitoring module enabled to monitor the condition of said first type camera devices to determine proper camera device operation and, to initiate a fault mode of upon detecting a fault condition in a first type camera device; and

ii) a transmission module, coupled to said monitoring module, for transmitting a control signal to control said second type camera device to monitor the area which was being monitored by said first type camera device corresponding to the detected fault condition.

12. The system of claim 11, wherein said control system further includes:

a detection module for generating a target detection signal while operating in said fault mode of operation, in response to receiving an indication that said second camera device detected a target; and

wherein said transmission module is configured to send the target detection signal to a guard interface unit without first requiring verification by another camera device.

13. The system of claim 12, wherein said control system includes:

a control module for assigning multiple second type camera devices to cover an area previously monitored by a first type camera device which had a fault that was detected by said monitoring module.

14. The system of claim 13, wherein said first type camera devices are fixed mount camera devices and wherein said second type camera devices are movable mount camera devices.

15. The system of claim 11, further comprising:

a first system control unit and a second system control unit, each of the first and second system control units controlling different sets of camera devices in said system, said first and second system control units each having the ability to take over control of at least some of the camera devices controlled by the other one of the first and second control units in the event of a detected fault of one of the first and second control units.

16. The system of claim 15, wherein the first system control unit includes:

a failsafe control module enabled to monitor for signals from camera devices controlled by said second control unit indicative of a fault condition in said second control unit.

17. The system of claim 16, wherein said fail safe control module includes:

a fault determination module for determining if a fault occurred in the second control unit based on information including a number of camera devices which indicate a fault in said second control unit relative to a number of camera devices which indicate no fault in the second control unit.

18. The system of claim 17, wherein said second system control unit includes:

a self test control module for controlling said second control system to perform by second system control unit with the result of the self test being communicated to the first control unit.

19. The system of claim 17, wherein the detection of the control unit fault is also a function of a test performed by the first system control unit on the second system control unit via signals transmitted over an interface existing between the first and second control units.

20. The system of claim 12, wherein said control system includes:

means for reverting to said normal mode of operation upon detecting that the faulty first type camera device has been restored to a non-fault condition.