Camera lens control system and method

• US 5,471,296 A
• Filed: 06/16/1993
• Issued: 11/28/1995
• Est. Priority Date: 05/31/1990
• Status: Expired due to Term

• Current Assignee: Thomson Licensing SA (Vantiva SA)
• Original Assignee: ParkerVision, Inc.
• Inventors: Sorrells, David F., Parker, Jeffrey L., Mix, John D.
• Primary Examiner(s): Buczinski, Stephen C.
• Application Number:
  US08/078,434
• Time in Patent Office: 895 Days
• Field of Search: 356/139.06, 356/141.2, 318/640, 250/203.3, 250/206.1, 352/53, 352/179, 348/169, 348/213
• US Class Current: 356/139.06
• CPC Class Codes: B25J 9/1697 Vision controlled systems
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: H04N 23/661 Transmitting camera control signals through networks, e.g. control via the Internet
• 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

Abstract

The system includes distance measuring capability for use in the local and remote control of a camera lens for automatic and programmable control of ZOOM perspective, FOCUS, IRIS and other functions of the camera in conjunction with the programming of an included microcomputer-controlled automatic tracking system.

Claims

1. A method of automatically controlling the field of view of a camera relative to a specific subject within the field of view of the camera by an automatic control system comprising the steps of:

A. identifying automatically by the automatic control system the specific subject that is to be within the field of view by detecting the subject;

B. determining by the automatic control system a relationship of the subject to the field of view of the camera;

C. controlling the field of view of the camera by the automatic control system in response to the determined relationship of step B; and

D. determining the distance between the subject and the camera.

2. The method of claim 1 wherein step A includes the step of:

E. automatically tracking the subject by the automatic control system in at least one plane with the field of view.

3. The method of claim 1 wherein step C includes the steps of:

E. establishing desired fields of view with respect to the distance between the subject and the camera;

F. automatically controlling the field of view to automatically maintain the desired fields of view established in step E.

4. The method of claim 3 further comprising the step of:

G. automatically issuing a command to the automatic control system to select a desired field of view established in step E.

5. The method of claim 4 wherein step F includes the step of:

H. issuing the command by the subject.

6. The method of claim 1 further including the step of:

E. establishing and remembering a plurality of fields of view.

7. The method of claim 6 wherein step E includes the step of:

F. issuing a command to the automatic control system to recall and maintain one of the desired fields of view remembered in step E.

23. The method of claim 3 wherein step D includes the steps of:

F. determining the actual error in position of the subject with respect to the field of view of the camera with respect to a reference established by the automatic control system;

G. establishing a desired location of the subject with respect to the field of view of the camera; and

H. automatically controlling the field of view by the automatic control system of the camera to maintain the subject at the desired location with respect to the field of view.

24. The method of claim 23 wherein step H includes the step of:

I. establishing a plurality of tracking zones wherein each tracking zone is defined by an error measured from a desired location of the subject relative to the field of view.

25. The method of claim 24 wherein step I includes the step of:

J. establishing a specific rate at which the error between the subject and the desired location is reduced in each tracking zone established in step I.

26. The method of claim 24 further including the step of:

J. automatically adjusting the tracking zones of step I to maintain a desired tracking zone area relative to the subject independent of distance.

27. The method of claim 24 further including the step of:

K. automatically controlling the rate at which the error is reduced within each tracking zone.

28. The method of claim 27 further including the step of:

L. maintaining the highest error reduction rate associated with a tracking zone that the subject has entered until the error has been substantially eliminated.

8. A method of automatically controlling the focus of the field of view of a camera by an automatic control system relative to a subject comprising the steps of:

A. automatically identifying the subject by the automatic control system by detecting the subject;

B. establishing a desired focus relative to the subject; and

C. automatically controlling the focus of the field of view by the automatic control system in response to a determined relationship between the subject of step A and the automatic control system.

9. The method of claim 8 wherein step B includes the step of:

D. determining the distance between the subject and the camera.

10. The method of claim 8 wherein step A includes the step of:

D. automatically tracking the subject to the automatic control system in at least one plane with the desired field of view.

11. The method of claim 8 wherein step C includes the step of:

D. automatically issuing a command to the automatic control system to select a desired focus established in step B.

12. The method of claim 11 wherein step D includes the step of:

E. issuing the command by the subject.

13. The method of claim 8 further including the step of:

D. establishing and remembering a plurality of focus settings.

14. The method of claim 13 wherein step D includes the step of:

E. issuing a command to the automatic control system to recall and maintain one of the desired focus settings remembered in step D.

15. A method of automatically controlling the field of view and field of view focus of a camera by an automatic control system with reference to a subject comprising the steps of:

A. automatically determining a relationship of the subject to the field of view of the camera;

B. establishing a desired field of view;

C. establishing a desired field of view focus;

D. controlling the field of view and focus by the automatic control system in accordance with step A.

16. The method of claim 15 wherein step A includes the step of:

E. determining the distance between the subject and the camera.

17. The method of claim 15 wherein step A includes the step of:

F. automatically tracking the subject in at least one plane with the field of view.

18. The method of claim 15 further including the step of:

E. remembering a plurality of fields of view established in step B.

19. The method of claim 15 further including the step of:

E. remembering a plurality of field of view focuses established in step C.

20. The method of claim 18 further including the step of:

F. automatically selecting the focus for each field of view.

21. The method of claim 20 further including the step of:

G. issuing a command to the automatic control system to recall a field of view remembered in step E and automatically selecting the focus for the recalled field of view.

22. The method of claim 21 wherein step G includes the step of:

H. issuing the command by the subject.

29. A method of automatically controlling the field of view of a camera relative to a subject within the field of view of the camera by an automatic control system comprising the steps of:

A. determining a relationship of the subject to the field of view of the camera;

B. establishing a plurality of desired fields of view;

C. controlling the field of view by the automatic control system to provide and maintain the desired fields of view established in step B.

D. determining the actual location of the subject with respect to the field of view of the camera;

E. establishing a desired location of the subject with respect to the field of view of the camera;

F. controlling the field of view of the camera by the automatic control system to automatically track the subject by reducing the error in position in the field of view between the actual location determined in step D and a desired location established in step E; and

G. establishing a tracking zone for each field of view established in step B wherein each tracking zone is defined by an area measured in terms of distance and angle from a reference that represents a desired location of the subject relative to the field of view established in step E.

30. The method of claim 29 wherein step G includes the step of:

H. establishing a specific rate at which the error in position between the subject and the field of view is reduced in each tracking zone established in step G for a respective field of view.

31. The method of claim 29 wherein step C includes the steps of:

H. selecting a desired field of view established in step B;

I. automatically selecting a tracking zone for the selected field of view of step G; and

J. automatically tracking the subject with the field of view of the camera.

32. The method of claim 31 wherein step J includes the step of:

K. reducing the error at the rate established for the selected tracking zone.

33. A method of automatically controlling the control functions used in an automatic control system that controls the field of view of a camera comprising the steps of:

A. automatically determining the error of a subject relative to a reference;

B. automatically determining the distance between a subject and the reference of step A;

C. automatically determining the relationship between the subject and the field of view;

D. selecting which of one or more control functions used for the control of the automatic control system and control of the camera field of view are to be automatically changed in response to changes in distance;

E. establishing a relationship between the distance and the control function selected in step D that determines how the control functions are to be changed in response to changes in the distance; and

F. automatically controlling one or more functions by the automatic control system in response to changes in the distance in accordance with the respective relationship established in step E.

34. The method of claim 33 wherein step C includes the step of:

F. selecting one or more control functions from the following list;

1. camera field of view;

2. camera focus;

3. camera iris;

4. tracking window size in PAN and/or TILT plane;

5. tracking sensitivity;

6. angular tracking range;

7. override speed in PAN and/or TILT plane;

8. framing; and

9. angular tracking zone.