Control of multiple image capture devices

• US 20030025800A1
• Filed: 07/15/2002
• Published: 02/06/2003
• Est. Priority Date: 07/31/2001
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Hunter, Andrew Arthur, Cheatle, Stephen Philip
• Granted Patent: US 7,075,567 B2
• Time in Patent Office: Days
• US Class Current: 348/208.13
• 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 13/19641 Multiple cameras having overlapping views on a single scene
• CPC Class Codes: G08B 13/19667 Details realated to data compression, encryption or encoding, e.g. resolution modes for reducing data volume to lower transmission bandwidth or memory requirements
• CPC Class Codes: H04N 19/103 Selection of coding mode or of prediction mode
• CPC Class Codes: H04N 19/137 Motion inside a coding unit, e.g. average field, frame or block difference
• CPC Class Codes: H04N 19/587 involving temporal sub-sampling or interpolation, e.g. decimation or subsequent interpolation of pictures in a video sequence
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A method and apparatus for controlling the operation of a system having a plurality of video cameras. The cameras are linked to a control unit which has a motion detection apparatus for monitoring the images received from the cameras and detecting motion therein. The cameras are adapted to operate in at least two modes: a low resolution mode and a high resolution mode. Under normal circumstances, cameras will be operating in low resolution mode to minimise use of system resources. If activity is detected within the field of view of one of the cameras, that camera is switched to high resolution, the other cameras remaining in the low resolution mode.

Claims

1. Control apparatus for receiving outputs from and controlling the operation of a plurality of image capture devices, at least some of said image capture devices being arranged to operate at any time in only one of at least two modes, the transmission bandwidth required to accommodate the outputs of image capture devices operating in the second mode being substantially less than that required to accommodate the outputs of image capture devices operating in the first mode, wherein all of the image capture devices are arranged, in use, to continuously transmit captured image data to the control apparatus, the control apparatus comprising monitoring apparatus for monitoring the outputs from one or more of said plurality of image capture devices, detection apparatus for detecting activity within the field of view of at least one of said image capture devices, and switching apparatus for switching or maintaining the operating mode of the image capture device within whose field of view activity is detected to the first operating mode, the image capture devices having fields of view within which no activity is taking place being arranged or caused to operate in said second operating mode.

2. Control apparatus according to claim 1, further comprising tracking apparatus for tracking the progress of said activity so as to determine when the occurrence of said activity has or will exit the field of view of said at least one image capture device, and prediction means for predicting which image capture devices field of view said activity will subsequently enter.

3. Control apparatus according to claim 1, comprising a central control unit for controlling the operation of said plurality of image capture devices.

4. Control apparatus according to claim 1, comprising a distributed control arrangement, local to each of a plurality of image capture devices, comprising a transmitter for transmitting a signal from a first image capture device operating in said first operating mode to a second image capture device in whose field of view activity is detected or predicted to take place to cause said second image capture device to switch from said second to said first operating mode.

5. Control apparatus according to claim 1, arranged to control the image capture devices such that they normally operate in a relatively low resolution, low frame rate or monochrome mode, and only switch the mode of an image capture device to high resolution, high frame rate or colour operation in the event that activity is detected within their field of view.

6. Control apparatus according to claim 1, including an adjustor for controlling the orientation and/or magnification of the field of view of an image capture device according to the determined or predicted location of said activity.

7. Control apparatus according to claim 1, including data representative of the arrangement of the image capture devices relative to each other.

8. Control apparatus according to claim 1, arranged to trigger an alarm or other type of alert mechanism in the event that an activity is detected within a monitored area and/or if such an activity continues for more than a predetermined period of time.

9. Control apparatus according to claim 1, wherein the control apparatus is in the form of an ethernet arrangement (or the like).

10. Control apparatus for receiving outputs from and controlling the operation of a plurality of image capture devices, at least some of said image capture devices being arranged to operate in one of at least two modes, the transmission bandwidth required to accommodate the outputs of image capture devices operating in the second mode being substantially less than that required to accommodate the outputs of image capture devices operating in the first mode, the control apparatus comprising monitoring apparatus for monitoring the outputs from one or more of said plurality of image capture devices, detection apparatus for detecting activity within the field of view of at least one of said image capture devices, tracking apparatus for tracking the progress of said activities so as to determine when the occurrence of said activity has or will exit the field of view of said at least one image capture device, prediction apparatus for predicting which image capture devices field of view said activity will subsequently enter, and switching apparatus for switching or maintaining the operating mode of the image capture device within whose field of view activity is detected or predicted to the first operating mode, the image capture devices having fields of view within which no activity is detected or predicted being arranged or caused to operate in said second operating mode.

11. Control apparatus according to claim 10, arranged to control the image capture devices such that they are normally “

off”

(second operating mode) and only switch the mode of an image capture device to “

on”

(first operating mode) in the event that activity is detected or predicted within its field of view.

12. Control apparatus according to claim 10, wherein all of the image capture devices are arranged to continuously transmit captured image data to the control apparatus.

13. A method of controlling the operation of a plurality of image capture devices, at least some of said image capture devices being arranged to operate at any time in only one of at least two modes, the transmission bandwidth required to accommodate the outputs of image capture devices in the second mode being substantially less than that required to operate image capture devices in the first mode, the method comprising the steps of providing monitoring apparatus for monitoring the outputs from said plurality of image capture devices, continuously transmitting captured image data from all of said image capture devices to said monitoring apparatus, detecting activity within the field of view of at least one of said image capture devices, and switching or maintaining the operating mode of the image capture device within whose field of view activity is detected to the first operating mode, the image capture devices having fields of view within which no activity is taking place being arranged or caused to operate in said second operating mode.

14. A method according to claim 13, including the step of triggering an alarm or other type of alert mechanism in the event that an activity is detected within a monitored area and/or of such an activity continues for more than a predetermined period of time.

15. A method of controlling the operation of a plurality of image capture devices, at least some of said image capture devices being arranged to operate in one of at least two modes, the transmission bandwidth required to accommodate the outputs of image capture devices operating in the second mode being substantially less than that required to accommodate the outputs of image capture devices operating in the first mode, the method comprising the steps of monitoring the outputs from said plurality of image capture devices, detecting activity within the field of view of at least one of said image capture devices, tracking the progress of said activity so as to determine when the occurrence of said activity has or will exit the field of view of said at least one image capture device, predicting which image capture devices field of view said activity will subsequently enter, and switching or maintaining the operating mode of the image capture devices within whose field of view activity is detected or predicted to the first operating mode, the image capture devices having fields of view within which no activity is detected or predicted being arranged or caused to operate in said second operating mode.

16. A method according to claim 16, including the step of controlling the image capture devices such that they are normally “

off”

or operate in a relatively low resolution, low frame rate or monochrome mode, and switching an image capture device “

on”

or switching its mode to high resolution, high pressure rate, or colour operation in the event that activity is detected within their field of view.