JPS5961374A - Focus display control system of television camera - Google Patents

Abstract

PURPOSE:To adjust surely and easily focus, by quantifying shift of focus of a television camera and displaying digitally the result continuously on a screen of a monitor television. CONSTITUTION:An error signal representing the amount of shift of focus is stored in a memory 12, based on an output of a detector 8 for object position and an output of a focus adjuster 6. A focus display control section 13 reads out error information from a memory 12, converts the information into character pattern information at a character generator 14 and applies the result to a signal synthesis section 15. The signal synthesis section 15 synthesizes this character pattern information and a video signal from the television camera 2 and applies the result to the monitor television 5 and a transmission control section 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a teleconference system in which focus error information is digitally displayed on a television screen in order to facilitate focus adjustment of a television camera. Regarding display control methods.

[Technology background]

BACKGROUND ART Recently, conferences called teleconferences have begun to be held between people in remote locations using television. This involves placing television cameras and television receivers at each meeting member's location and transmitting images and audio to each other, creating the same situation as if everyone were meeting in one room. Each member location is
Normally, one or more television cameras are placed and operated as appropriate by meeting members, and conventionally the focus adjustment was done by remote control while watching a television monitor. However, this focus adjustment is usually performed by meeting members by looking at the blurred image displayed on the monitor TV, so there are individual differences in the adjustment status, and the image quality remains unimproved, or the depth of focus may change. (The operation is delicate, so it was extremely troublesome to use it between meetings.)

[Object and structure of the invention]

An object of the present invention is to provide a means for reliably and easily adjusting the focus of a conference television, and specifically, to provide a means for digitally displaying the focusing state on the screen. be.

The present invention provides, as a configuration for that purpose, a television camera having a focus moving means controlled by a remote switch, a monitor television, a means for continuously detecting the subject position, and a current state of the television camera. comprising means for calculating a focus error amount from the focus position and subject position, and means for continuously digitally displaying the focus error amount on a monitor television screen,
By monitoring the amount of focus error digitally displayed on the monitor TV screen and operating the remote switch mentioned above,
It is characterized by making it possible to minimize the amount of focus error.

[Embodiments of the Invention] FIG. 1 shows the basic configuration of a general conference television system. In the figure, 1 and 1' are member groups that make up the conference, including members A and B.

C, J), and E. 2 and 2' are television cameras, 3 and 3' are transmission control units, 4 and 4' are conference televisions, and 5
．． 5' is a monitor television, 6 and 6' are focus adjusters, and 7.
7' is a remote switch.

Conference member group 1 is imaged by camera 2,
The other party's conference television 4' via the transmission control units 3 and 3'
The video is output to. The conference member group 1' of the other party is imaged by the television camera 2' and the image is output to the conference television 4.

Focus adjustment is carried out by meeting members who adjust the focus adjusters 6 and 6' from 1 to 1 while watching their respective monitor televisions 5 and 5' so that the images are as clear as possible. , the remote switches 7, 7' are operated 0N10FF, and the focus t1 adjusters 6, 6' are used to drive the camera's focus movement morph back and forth and stop it at the in-focus position.

The present invention adds a mechanism to such a conventional system to quantify the state of out-of-focus and digitally display it on a part of the television screen, and will be described below with reference to embodiments.

FIG. 2 is a configuration diagram of a system according to an embodiment of the present invention. This figure corresponds to element parts 1 to 5 in FIG. 1, and the same numbers in the figures basically represent the same functions. Further, 2a is a synchronization signal line, 6a is a focal position signal line,
8 is a subject position detector, 8a is a subject position signal line, 10
is a subtraction circuit, 11 is an A/D converter, 12 is a memory, 13
14 is a focus display control unit, 14 is a character generator, 15 is a signal synthesis unit, 16.16' is a focus error information display, 17 is a remote switch that adjusts the focus of the other party's image, and 18 is a focus from the other party's remote switch. The alignment operation signal line is shown.

As the object position detector 8, various known means can be used, such as a distance measurement method using ultrasonic wave echo, or a triangulation method using double image matching, and an appropriate sampling period (for example, 0 .3 to 0.5 seconds), an analog signal representing the distance between the subject and the camera is output to the signal line 8a. On the other hand, from the focus adjuster 6,
A analog signal indicating the current focal position of the camera is taken out to the signal line 6a.

The subtracter 10 creates a difference between the two signals on the signal lines 6a and 8a, and outputs an error signal of 1" representing the out-of-focus scene. This error code is converted into a digital signal by the A/D converter 11. It is converted and stored as error information in the memory 12.
If the two signals taken out from the focus adjuster 6 and the subject position detector 8 are expressed in digital quantities, the subtracters 10 and the like may be of digital type.

Then, the A/D converter 11 becomes unnecessary. Further, the error signal is expressed by, for example, + and - polarities and a distance in units of 10 cm.

The focus display control unit 1; 3 extracts a synchronization signal from the TV camera 2 through the signal line 2a, reads error information in digital format from the memory 12 at a timing corresponding to the digital focus display position on the TV screen, and generates characters. The character pattern information is converted into character pattern information by the device 14 and supplied to the signal synthesis section 15.

The signal synthesis section 15 synthesizes the character pattern information and the video signal output from the television camera 2, and supplies the synthesized signal to the monitor television 5 and the transmission control section 31C.

The focus error information is displayed on the monitor TV 5 and the other party's conference TV 4' (Fig. 1), along with images of the meeting members, in a size that is easy to see, as shown by the error information display 16 and 16' in the corner of the screen. is displayed as a number.

The conference member 1 controls the focus adjuster 6 by operating the remote switch 7 while watching the focus error information display 16 on the monitor television 5, so that the focus error information display 16 becomes 10. Regarding the video of the other party, while looking at the focus error information display 16' displayed on the screen of the conference television 4, operate the remote switch 17 L and send the other party's Σ - Similar focusing can be achieved by controlling the focus adjuster 6' of the review camera.

When a meeting member of the other party filj adjusts the focus of his or her TV camera, a corresponding remote switch 17' (not shown) is used to adjust the focus of the TV camera.
A switch operation signal can be sent to the signal line 18 via the transmission control units 3' and 3 to control the focus adjuster 6.

The transmission control unit 3.3' is a remote switch 17.17'.
When a character is played, the operation signal is transmitted using, for example, a specific band or a specific frame in the video signal2, and the transmitted operation signal is separated from the video signal, It is supplied to each heat spot regulator 6, 6'.

Note that it is also possible to display the focus error information table only on the monitor television screen 1 and not to display it on the conference television screen. In this way, when the other party's video adjustment is not performed, the mechanism of the transmission control section may be the same as the conventional one.

〔Effect of the invention〕

As described above, according to the present invention, the defocus state of the television camera is quantified and continuously digitally displayed on the monitor television screen, so that members of the television conference can easily perform remote operations. Focus adjustment can be performed at any time, and uniform adjustment results can be obtained no matter who the operator is.Furthermore, focus adjustment from a remote location can improve the quality of the image.

[Brief explanation of drawings]

FIG. 1 is a basic configuration diagram of a video conference system, and FIG. 2 is a configuration diagram of an embodiment of the present invention. In the figure, 1 is the subject meeting member, 2 is the TV camera,
3 is a transmission control unit, 4 is a conference TV, 5 is a monitor TV, 6 is a focus adjuster, 7 and 17 are remote switches, 8 is a subject position detector, 9 is a focus display control unit, 16 and 16' are Indicates focus error information display. Patent applicant: Shiren Hatake Co., Ltd. Patent attorney: Fumihiro Hase (1 other person) -41:

Claims (1)

[Claims] In a video conferencing system, a television camera with a focus moving means controlled by a remote switch, a monitor television, a means for continuously detecting the subject position, and a focus error based on the current focal position of the television camera and the subject position are used. comprising means for calculating the amount of focus error, and means for continuously digitally displaying the focus error amount on a monitor television screen,
By monitoring the amount of focus error digitally displayed on the monitor TV screen and operating the above remote switch,
A TV camera focus display control method that makes it possible to minimize focus errors.