Security system with maskable motion detection and camera with an adjustable field of view

• US 6,727,938 B1
• Filed: 04/14/1997
• Issued: 04/27/2004
• Est. Priority Date: 04/14/1997
• Status: Expired due to Term

• Current Assignee: Robert Bosch Gmnh
• Original Assignee: Robert Bosch GmbH
• Inventors: Randall, Jennifer L.
• Primary Examiner(s): Kelley, Chris
• Assistant Examiner(s): VO, TUNG T
• Application Number:
  US08/834,073
• Time in Patent Office: 2,570 Days
• Field of Search: H04/N.718, 348/143, 348/144, 348/150, 348/151, 348/155, 348/154, 348/207, 348/159, 348/169-172, 348/211, 348/213, 348/145, 348/162, 348/161, 395/141
• US Class Current: 348/143
• CPC Class Codes: G08B 13/19602 Image analysis to detect motion of the intruder, e.g. by frame subtraction
• CPC Class Codes: G08B 13/19606 Discriminating between target movement or movement in an area of interest and other non-signicative movements, e.g. target movements induced by camera shake or movements of pets, falling leaves, rotating fan
• CPC Class Codes: G08B 13/19689 Remote control of cameras, e.g. remote orientation or image zooming control for a PTZ camera
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source

Abstract

A security system with a Pan/Tilt/Zoom Camera and maskable motion detection is disclosed. At selected fields of view of the P/T/Z camera, masks are created to mask, from motion detection, select sub-areas within the selected field of view. The mask created for the selected view may be saved in memory. The saved mask may be recalled and reapplied to the motion detector whenever the P/T/Z camera is repositioned to the field of view corresponding to the saved mask. The commands required to reposition the camera to each selected field of view may also be saved. The mask and repositioning commands can be associated with each other, so that selecting a target view corresponds to selecting the commands to position the camera to that view, as well as the mask to be applied for this view.

Claims

1. A surveillance system comprising:

a video camera having an adjustable field of view,

a motion detector for detecting motion within a selected field of view of said camera, said motion detector including;

mask for masking portions of said video camera'"'"'s, field of view from said motion detecting, and

means for loading a mask image into said mask, and said surveillance system further including,

means for selecting a target mask image from among a set of target mask images, said selecting being in dependence upon said selected field of view of said camera, wherein said motion detecting is performed on the target mask image selected.

2. A surveillance system as in claim 1, wherein said system further comprises:

a pan motor for rotating the video camera about a horizontal axis,

a tilt motor for rotating the video camera about a vertical axis, and

a zoom motor for magnifying and demagnifying the video camera'"'"'s field of view.

3. A surveillance system as in claim 1, wherein said system further comprises:

means for adjusting said camera'"'"'s field of view via one or more camera positioning commands,

means for storing a set of camera positioning commands, corresponding to the video camera'"'"'s field of view, into a memory,

means for selecting a set of target positioning commands from said memory,

means for communicating said set of target positioning commands to the camera, to adjust said camera'"'"'s field of view.

4. A surveillance system as in claim 3, wherein said system further comprises:

means for selecting a target field of view,

wherein said means for selecting a set of target positioning commands and said means for selecting the target mask image are both dependent upon the selected target field of view.

5. A surveillance system as in claim 1, further comprising:

means for creating and storing one or more target mask images corresponding to the camera'"'"'s field of view.

6. A surveillance system as in claim 5, further comprising:

means for selecting from among the masked images corresponding to the same field of view in dependence upon a mask selection parameter.

7. A surveillance system as in claim 6, wherein said mask selection parameter is the time of day.

8. A surveillance system as in claim 6, wherein said mask selection parameter is the day of the week.

9. A surveillance system as in claim 5, wherein said means for creating said target mask images comprises:

means for creating a mask image in dependence upon a previously created mask image.

10. A surveillance system as in claim 5, wherein said means for creating said target mask images comprises:

means for creating a mask image in dependence upon detected motion within the video camera'"'"'s field of view.

11. A surveillance system as in claim 1, wherein said system further comprises:

means for deactivating the motion detector when the camera'"'"'s adjustable field of view is being adjusted.

12. A surveillance system as in claim 1, wherein said system further comprises:

means for activating said motion detector upon completion of said loading of the mask image.

13. A method for selective area motion detection, utilizing a camera with an adjustable field of view and a motion detector having a loadable mask, said method comprising the steps of:

adjusting the camera to select a field of view,

loading a mask image corresponding to said field of view selected into said loadable mask

performing motion detection on said mask image corresponding to said field of view selected.

14. A method for selective area motion detection as in claim 13, wherein said adjusting of the camera comprises the steps of:

selecting a predefined camera position,

communicating camera positioning commands corresponding to this selected position, and

adjusting the camera in accordance with said camera positioning commands.

15. A method for selective area motion detection as in claim 13, wherein said loading of the mask comprises the steps of:

selecting a predefined mask image corresponding to said field of view,

communicating the selected mask image to the motion detector, and,

loading the selected mask image into the loadable mask.

16. A method for selective area motion detection as in claim 13, wherein said adjusting of the camera comprises the steps of:

selecting a predefined camera position,

communicating camera positioning commands corresponding to this selected position, and

adjusting the camera in accordance with said camera positioning commands; and

, said loading of the mask comprises the steps of;

selecting a predefined mask image corresponding to said field of view,

communicating the selected mask image to the motion detector, and,

loading the selected mask image into the loadable mask.

17. A method for selective area motion detection as in claim 16, wherein said selecting of the predefined camera position and said selecting of the predefined mask image are accomplished by:

selecting an address with which said predefined camera position and predefined mask image are both associated.

18. A method for selective area motion detection, utilizing a camera with an adjustable field of view and a motion detector having a maskable picture area, said method comprising the steps of:

adjusting the camera to produce a set of camera fields of view,

creating a picture area mask for each of said camera fields of view,

storing camera parameters in correspondence with each of said camera fields of view,

storing each of said picture area masks in correspondence with each of said camera fields of view,

adjusting said camera in accordance with one of the set of said stored camera parameters,

loading said stored picture area mask corresponding to field of view into the motion detector,

applying said mask to said maskable picture area to produce a masked picture area,

so that subsequent motion detection by said motion detector does not include motion within said-masked picture area.