METHOD AND APPARATUS FOR PROVIDING MOTION CONTROL SIGNALS BETWEEN A FIXED CAMERA AND A PTZ CAMERA

• US 20070236570A1
• Filed: 04/05/2006
• Published: 10/11/2007
• Est. Priority Date: 04/05/2006
• Status: Active Grant

• Current Assignee: Etreppid Technologies LLC
• Original Assignee: Etreppid Technologies LLC
• Inventors: Sun, Zehang, Zhang, Yongmian
• Granted Patent: US 7,636,105 B2
• Time in Patent Office: Days
• US Class Current: 348/159
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• 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 29/186 Fuzzy logic; neural networks
• CPC Class Codes: H04N 17/002 for television cameras
• CPC Class Codes: H04N 23/695 Control of camera direction for changing a field of view, e.g. pan, tilt or based on tracking of objects
• CPC Class Codes: H04N 23/90 Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums

Abstract

The method and apparatus for providing motion control signals between a fixed lens static camera and a PTZ camera that includes an adjustable-in-use focal length adapted to provide improved surveillance. In one aspect of the present invention, the improved method and apparatus includes an improved PTZ process in which fuzzy logic based information is utilized to achieve a set of more reliable P/T/Z parameters. In another aspect of the invention, the fixed lens static camera and the PTZ camera are mounted vertically on top of each other. In another aspect of the present invention, there is provided an automatic self-calibration between the fixed lens static camera and the PTZ camera. In another aspect of the present invention, there is provided a cost-effective standalone single board DSP solution.

Claims

1. A method for taking a picture of an object comprising:

providing in a substantially fixed positional relationship to each other a camera having a broad focal area and a PTZ camera having an adjustable-in-use focal length;

detecting the object within a field of view of the camera;

obtaining a size of the object and location of the object within the field of view of the camera;

determining, using the size of the object and the location of the object, PTZ parameters that provide a desired location of the PTZ camera, the PTZ parameters including a focal length PTZ parameter that will allow for the PTZ camera to take a recognizable picture of the object;

moving the PTZ camera to the desired location based on the PT parameters; and

taking the picture of the object with the PTZ camera based on the determined focal length Z parameter.

2. The method according to claim 1, wherein:

the object moves, and the desired location thus moves, and the step of determining takes into account the movement of the object; and

the steps of determining and moving are repeated in order to track the moving object.

3. The method according to claim 2 wherein during certain ones of the repeated steps of determining, the step of determining uses information derived from image signals captured from the PTZ camera to assist in determining PTZ parameters and, wherein the step of determining uses fuzzy logic to fuse the information from the PTZ camera with information from the camera.

4. The method according to claim 1 further including the step of automatic self-calibration of the position of the camera and the PTZ camera relative to each other.

5. The method according to claim 1 wherein the automatic self-calibration uses a feature point tracking algorithm to obtain a correlation map between the static camera and the PTZ camera.

6. The method according to claim 1 wherein the step of determining uses a look-up table as part of the controlling algorithm.

7. The method according to claim 1 wherein the look-up table provides for a correlation map between size of the object in the camera and the adjustable-in-use focal length.

8. The method according to claim 7 wherein the look-up table further provides correlation between a signal representative of a location of the object within the field of view of the camera and pan and tilt parameters.

9. An apparatus for taking a picture of an object comprising:

a camera having a broad focal area;

a PTZ camera having an adjustable focal length, wherein the camera and the PTZ camera

are mechanically mounted such that a fixed position between the camera and the PTZ camera remains substantially constant;

a processor electrically connected to the camera and the PTZ camera, the processor;

obtaining a size of the object and location of the object within the field of view of the camera;

determining, using the size of the object and the location of the object, PTZ parameters that provide a desired location of the PTZ camera, the PTZ parameters including a focal length PTZ parameter that will allow for the PTZ camera to take a recognizable picture of the object; and

outputting the PTZ parameters to the PTZ camera,

wherein the PTZ camera is adapted to move to the desired location based on the PT parameters and takes the picture of the object using the determined focal length Z parameter.

10. The apparatus according to claim 9 wherein, the processor determines the desired location using derived from image signals captured from the PTZ camera and fuzzy logic to fuse the information from the PTZ camera with information from the camera.

11. The apparatus according to claim 9 wherein the processor further provides automatic self-calibration to adjust for small changes in the position between the camera and the zoom camera.

12. The apparatus according to claim 11 wherein the automatic self-calibration performed by the processor includes using a feature point tracking algorithm to obtain a correlation map between the static camera and the PTZ camera.

13. The apparatus according to claim 9 wherein the processor is housed on a single printed circuit board.

14. The apparatus according to claim 9 wherein a housing of the zoom camera is mechanically mounted with another housing of the camera.

15. The method according to claim 14 wherein the camera and the PTZ camera are mounted vertically on top of each other.

16. The method according to claim 9 wherein the processor is a standalone single board digital signal processor.

17. The apparatus according to claim 16 wherein the processor is housed on a single printed circuit board.

18. The apparatus according to claim 9 wherein the computer repeats a sequence of inputting, determining and outputting and wherein the picture is retaken during each sequence.