Remote camera control system with compensation for signal transmission delay

• US 5,838,368 A
• Filed: 06/18/1993
• Issued: 11/17/1998
• Est. Priority Date: 06/22/1992
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ohiwa, Yasuyuki, Masunaga, Makoto
• Primary Examiner(s): Garber, Wendy
• Assistant Examiner(s): Ho, Tuan V.
• Application Number:
  US08/079,616
• Time in Patent Office: 1,978 Days
• Field of Search: 348/211, 348/214, 348/207, 348/142, 348/143, 348/14, 348/15, 348/16, 348/169, 348/170, 348/36, 348/37, 348/39
• US Class Current: 348/211.9
• CPC Class Codes: H04N 23/66 Remote control of cameras or camera parts, e.g. by remote control devices
• CPC Class Codes: H04N 7/142 Constructional details of the terminal equipment, e.g. arrangements of the camera and the display
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source

Abstract

In a camera control system, a video signal from a camera is displayed on a monitor with some delay. An operation signal from a joystick disposed on the side of the monitor is transmitted to a data comparison circuit through a transmission system, a control unit and a counter. A panning operation on the camera is performed through a motor by applying a driving signal from a panhead driving circuit according to a difference between the operation signal and panning position detection data from a panning position detector. After that, in response to a signal indicating a stop of operation on the joystick, the control unit sends delayed panning position detection data obtained from a data delay circuit to the data comparison circuit. The panned position of the camera is thus shifted back to the panning position indicated by the delayed data obtained when the panning operation is stopped. The tilting and zooming operations on the camera can be controlled also in the same manner.

Claims

1. A camera control system comprising:

a) a camera arranged to pick up an image of an object of shooting and to output a image signal;

b) coding means arranged to code said image signal and to output image data;

c) transmission means for transmitting said image data to a designated place;

d) decoding means arranged to decode said image data sent through said transmission means and to output a image signal obtained by decoding;

e) display means for displaying a video image of said object carried by said image signal outputted from said decoding means;

f) driving means for performing a driving action to vary a shooting condition of said camera;

g) detection means arranged to detect the shooting condition of said camera and to output state data indicating the shooting condition of said camera;

h) delay means arranged to delay said state data for a predetermined period of time and to output delayed state data;

i) operation means arranged to output operation data indicating an instruction for varying the shooting condition of said camera; and

j) control means arranged to give to said driving means an instruction signal for varying the shooting condition of said camera on the basis of said state data and said operation data while said operation means is in the process of being operated and, when said operation means is stopped from being operated, to give to said driving means an instruction signal for varying the shooting condition of said camera on the basis of said state data and said delayed state data obtained when said operation means is stopped from being operated.

2. A system according to claim 1, wherein said shooting condition includes at least one of panning, tilting and zooming positions of said camera.

3. A system according to claim 1, wherein said shooting condition includes an exposure condition of said camera.

4. A system according to claim 1, further comprising freezing means for freezing a display of an image picked up by said camera, while said instruction signal for varying the shooting condition of said camera is being given to said driving means on the basis of said state data and said delayed state data obtained when said operation means is stopped from being operated.

5. A system according to claim 1, wherein said shooting condition includes at least one of panning, tilting and zooming positions of said camera.

6. A system according to claim 1, wherein said shooting condition includes an exposure condition of said camera.

7. A system according to claim 1, further comprising freezing means for freezing a display of an image picked up by said camera, while said instruction signal for varying the shooting condition of said camera is being given to said driving means on the basis of said state data and said delayed state data obtained when said operation data stops being received by said control means.

8. An image conference system comprising:

a) camera means arranged to pick up an image of an object of shooting and to output a image signal;

b) coding means arranged to code said image signal and to output image data;

c) transmission means for transmitting said image data to a designated place;

d) decoding means arranged to decode said image data sent through said transmission means and to output a image signal obtained by decoding;

e) display means for displaying a video image of said object carried by said image signal outputted from said decoding means;

f) driving means for performing a driving action to vary a shooting condition of said camera;

g) detection means arranged to detect the shooting condition of said camera and to output state data indicating the shooting condition of said camera;

h) delay means arranged to delay said state data for a predetermined period of time and to output delayed state data;

i) operation means arranged to output operation data indicating an instruction for varying the shooting condition of said camera; and

j) control means arranged to give to said driving means an instruction signal for varying the shooting condition of said camera on the basis of said state data and said operation data while said operation means is in the process of being operated and, when said operation means is stopped from being operated, to give to said driving means an instruction signal for varying the shooting condition of said camera on the basis of said state data and said delayed state data obtained when said operation means is stopped from being operated,

wherein, said means a) to j) being arranged in combination as one set, there are provided a plurality of sets of said means a) to j), which are interconnected through said transmission means.

9. A camera control system comprising:

a) a camera arranged to pick up an image of an object of shooting and to output a image signal;

b) coding means arranged to code said image signal and to output image data;

c) transmission means for transmitting said image data to a designated place;

d) decoding means arranged to decode said image data sent through said transmission means and to output a image signal obtained by decoding;

e) display means for displaying a video image of said object carried by said image signal outputted from said decoding means;

f) driving means for performing a driving action to vary an exposure of said camera;

g) detection means arranged to detect a level of the image signal outputted from said camera and to output level data;

h) delay means arranged to delay said level data for a predetermined period of time and to output delayed level data;

i) operation means arranged to output operation data indicating an instruction for varying the exposure of said camera; and

j) control means arranged to give to said driving means an instruction signal for varying the exposure of said camera on the basis of said level data and said operation data while said operation means is in the process of being operated and, when said operation means is stopped from being operated, to give to said driving means an instruction signal for varying the exposure of said camera on the basis of said level data and said delayed level data obtained when said operation means is stopped from being operated.

10. An image communication terminal unit comprising:

a) a camera arranged to pick up an image of an object of shooting and to output an image signal;

b) a display device for displaying said image signal; and

c) control means arranged to perform predetermined control over said camera and, after said predetermined control, to perform reverse control over said camera in a direction reverse to the direction of movement of said camera of said predetermined control as much as an amount of movement of said camera corresponding to a time delay of said predetermined control.

11. A unit according to claim 10, wherein said control means is arranged to freeze a display of an image picked up by said camera at least during the process of said reverse control over said camera.

12. A unit according to claim 11, wherein said control means is arranged to freeze a display of an image picked up by said camera for a length of time during which said time delay exists in said predetermined control over said camera in addition to a length of time required for said reverse control over said camera.

13. A unit according to claim 10, further comprising:

d) storing means for storing a designated control position of said camera;

e) input means arranged to permit inputting an operation to be performed on said camera;

f) mode designating means for selectively designating either a manual operation mode or a preset operation mode; and

g) driving means arranged to operate said camera at a low speed according to an input obtained by said input means in said manual operation mode and, in said preset operation mode, to operate and move said camera at a high speed to a position corresponding to a preset position stored in said storing means for a predetermined operation designated by said input means.

19. A system according to claim 13, wherein said control means is arranged to freeze a display of an image picked up by said camera at least during the process of said reverse control.

14. A camera control system comprising:

a) a camera arranged to pick up an image of an object of shooting and to output an image signal;

b) input means arranged to permit inputting an operation to be performed on said camera and to output a signal corresponding to the operation;

c) control signal forming means for forming a control signal for controlling said camera according to the signal outputted from said input means;

d) processing means arranged to form a reverse control signal for a predetermined amount of reverse movement of the camera in a direction reverse to the direction in which the camera operates according to the control signal upon termination of the control signal outputted from said control signal forming means and to freeze a display of the object image picked up by said camera for a length of time including at least a length of time between the end of the operation of said input means and the end of said predetermined amount of reverse movement of the camera; and

e) control means for controlling said camera according to an output of said control signal forming means and an output of said processing means.

15. A system according to claim 14, wherein said control means is arranged to control at least one of panning means, tilting means and zooming means provided for said camera.

16. A camera control system for controlling a camera, comprising:

a) storing means for storing designated control positions of camera control elements of said camera;

b) input means for permitting input of an operation to be performed on said camera;

c) mode designating means for designating at least either a manual operation mode or a preset operation mode;

d) driving means for driving each of said camera control elements at a designated speed; and

e) control means for controlling said driving means, said control means being arranged to cause said driving means to drive, in said manual operation mode, at a low speed the camera control element corresponding to the input obtained by said input means and to drive, in said preset operation mode, at a high speed the camera control element designated by said input means to a position corresponding to a preset position of said designated camera control element stored in said storing means, and said control means being further arranged such that, in carrying out predetermined control over a driving action of each of said camera control elements, said control means performs a reverse control over said camera in a direction reverse to the direction of movement of said camera of said predetermined control to an amount of said camera corresponding to a time delay resulting from said predetermined control.

17. A system according to claim 16, wherein said camera control elements include at least one of panning means, tilting means and zooming means for said camera.

18. A system according to claim 16, further comprising priority designating means for designating priority of control over said camera control elements being controlled.

20. A camera control system comprising:

a) coding means arranged to code an image signal outputted by a camera, and to output image data;

b) transmission means for transmitting said image data to a designated place;

c) driving means for performing a driving action to vary a shooting condition of said camera;

d) detection means arranged to detect the shooting condition of said camera and to output state data indicating the shooting condition of said camera;

e) delay means arranged to delay said state data for a predetermined period of time and to output delayed state data; and

f) control means for receiving operation data indicating an instruction for varying the shooting condition of said camera and arranged to give said driving means an instruction signal for varying the shooting condition of said camera on the basis of said state data and said delayed state data obtained when said operation data stops being received by said control means.