Method and apparatus for producing frame accurate position data in a PTZ dome camera with open loop control

• US 20060203098A1
• Filed: 12/06/2005
• Published: 09/14/2006
• Est. Priority Date: 02/19/2004
• Status: Active Grant

• Current Assignee: Bosch Security Systems Incorporated (Robert Bosch GmbH), Robert Bosch GmbH
• Original Assignee: Bosch Security Systems Incorporated (Robert Bosch GmbH), Robert Bosch GmbH
• Inventors: Henninger, Paul E. III, Bell, Mark, Magid, Bruce
• Granted Patent: US 7,643,066 B2
• Time in Patent Office: Days
• US Class Current: 348/211.990
• CPC Class Codes: G06T 7/254 involving subtraction of images
• CPC Class Codes: G06V 10/147 Details of sensors, e.g. sensor lenses fingerprint or palmprint sensors G06V40/13; vascular sensors G06V40/145; eye sensors G06V40/19
• CPC Class Codes: G06V 10/16 using multiple overlapping images; Image stitching
• CPC Class Codes: G06V 10/24 Aligning, centring, orientation detection or correction of the image
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• CPC Class Codes: G08B 13/19686 Interfaces masking personal details for privacy, e.g. blurring faces, vehicle license plates
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/6811 based on the image signal
• CPC Class Codes: H04N 23/6815 by distinguishing pan or tilt from motion
• CPC Class Codes: H04N 23/682 Vibration or motion blur correction
• CPC Class Codes: H04N 23/6845 by combination of a plurality of images sequentially taken
• CPC Class Codes: H04N 23/80 Camera processing pipelines; Components thereof
• CPC Class Codes: H04N 7/185 from a mobile camera, e.g. for remote control

Abstract

A method of processing video images includes capturing a first image with a camera having a first field of view. The capturing occurs at a first point in time. Commands are transmitted to the camera to make pan, tilt and zoom movements. A second image is captured with the camera at a second point in time. The second point in time is after the movements have commenced. A second field of view of the camera is calculated at the second point in time. The calculating is based upon the commands. The second image is processed based upon the first field of view and the calculated second field of view.

Claims

1. A method of processing video images, comprising:

capturing a first image with a camera having a first field of view, said capturing occurring at a first point in time;

transmitting commands to said camera to make pan, tilt and zoom movements;

capturing a second image with said camera at a second point in time, the second point in time being after the movements have commenced;

calculating a second field of view of said camera at the second point in time, said calculating being based upon the commands; and

processing the second image based upon the first field of view and the calculated second field of view.

2. The method of claim 1 wherein said processing step includes determining a desired location of a mask in the second image.

3. The method of claim 1 wherein said processing step includes determining movement of an object of interest between the first image and the second image.

4. The method of claim 1 wherein the first field of view and the second field of view are each defined by a pan position, a tilt position, and a zoom multiplication factor, the commands including pan, tilt, and zoom commands, said calculating step including converting the zoom commands into the zoom multiplication factor.

5. The method of claim 4 wherein said converting includes accessing stored conversion information relating positions of a zoom stepper motor to the zoom multiplication factor.

6. The method of claim 4 wherein said calculating step is initiated and completed between a time of a frame interrupt and a time of a response signal.

7. A video system comprising:

a video camera including an image-capturing device configured to capture images, each captured image associated with a field of view of said camera;

a display device configured to display the images captured by said camera;

an actuating device configured to cause said camera to execute pan, tilt and zoom commands to thereby change the field of view of said camera;

a camera module configured to automatically produce camera zoom position information based upon the zoom commands; and

a processing device operably coupled to said camera and to said display device wherein said processing device receives images captured by said camera, said processing device being operable to calculate the field of view of said video camera based upon the pan commands, the tilt commands, and the camera zoom position information.

8. The video system of claim 7 wherein said camera module is configured to automatically update the camera zoom position information for each subsequent video frame.

9. The video system of claim 7 wherein said camera module is configured to transmit the camera zoom position information via serial communication in response to a frame interrupt.

10. The video system of claim 7 wherein said camera module is configured to calculate a change in zoom position between a time of the frame interrupt and a time of a response signal.

11. The video system of claim 7 wherein said processing device includes a memory device, said processing device being configured to respond to a field interrupt by retrieving field of view data stored in said memory device, and matching the field of view data to a frame being processed.

12. The video system of claim 11 wherein the retrieved field of view data includes pan position data associated with a mask and tilt position data associated with the mask.

13. The video system of claim 7 wherein the field of view is defined by a pan position, a tilt position, and a zoom multiplication factor, the camera zoom position information including zoom multiplication factor data, said processing device being configured to match the zoom multiplication factor data with pan position data and tilt position data.

14. A video system comprising:

a video camera including an image-capturing device configured to capture images, each captured image associated with a field of view of said camera;

a display device configured to display the images captured by said camera;

an actuating device configured to cause said camera to execute pan, tilt and zoom commands to thereby change the field of view of said camera; and

a processing device operably coupled to said camera and to said display device wherein said processing device receives images captured by said camera, said processing device being operable to calculate the field of view of said video camera as a function of time dependent upon the pan, tilt and zoom commands, and to output both the calculated field of view and a qualification of the calculated field of view, the qualification being based upon a point in time associated with the calculated field of view.

15. The system of claim 14 wherein said processing device is operable to output both the calculated field of view and a frame corresponding to the calculated field of view.

16. The system of claim 14 wherein said processing device includes field programmable gate array circuitry.

17. The system of claim 14 wherein said processing device is operable to generate at least one of said pan commands, tilt commands and zoom commands.

18. The system of claim 14 wherein said processing device is operable to generate a digital signal indicating validity of the calculated field of view.

19. The system of claim 14 wherein said actuating device includes a zoom stepper motor, the calculated field of view including a zoom multiplication factor, said processing device being configured to relate the zoom commands to positions of said zoom stepper motor, and to access stored conversion information relating the positions of said zoom stepper motor to the zoom multiplication factor.

20. The system of claim 14 wherein said processing device is configured to use the calculated field of view to at least one of:

determine a desired location of a mask in an image; and

track movement of an object of interest in the image.