JPH08149333A - Controller for television camera - Google Patents

Abstract

PURPOSE: To prevent the synchronization of a video signal displayed on a monitor or the like from being disturbed through the changeover of a camera by making fields of plural TV cameras coincident with each other. CONSTITUTION: Plural cameras 2 are connected to one set of controller 1 and the controller 1 selects a video signal from each camera 2 and provides the output of the selected signal. A camera control section 12 is provided corresponding to the cameras 2, a vertical pulse generating section 13 generates a pulse synchronously with the vertical synchronizing signal from a synchronizing signal generating section 11 and the pulse is sent to the camera through a transmission cable 16 with an input output section 15 via a vertical pulse control section 14. Each camera 2 generates a synchronizing signal synchronously with the vertical pulse and sends the video signal synchronously with the synchronizing signal to each camera control section 12 through a transmission cable. The video signal is given to a synchronizing separator section 17 from an input output section 15, in which the synchronizing signal is separated and fed to a field comparator section 18, where the synchronizing signal is compared with a synchronizing signal from the synchronizing signal generating section 11 in terms of fields, and when they are dissident, the signal is given to the vertical pulse control section 14, by which transmission of one or odd number of vertical pulses is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system in which a plurality of television cameras (hereinafter abbreviated as cameras) are synchronized with a signal from a controller and the video signal from each camera is switched by the controller and output. Regarding what matches the fields of.

[0002]

2. Description of the Related Art A plurality of cameras are connected to one controller, a reference signal for vertical synchronization is sent from each controller to each camera, and a synchronization signal generating circuit provided in each camera is controlled by a PLL circuit or the like from the controller. There is a method in which a synchronization signal synchronized with the reference signal is generated, and a video signal synchronized with this synchronization signal is output from each camera and switched by a controller for output. In this case, whether the field of the video signal generated by the camera is odd or even is determined arbitrarily by the synchronization signal generation circuit inside the camera, and the odd / even of this field must be specified from the controller. I can't. Therefore, when changing the camera with the controller, if the field (odd or even) of the camera before and after the change is different, the monitor etc. will not be synchronized when the camera is changed, and the synchronization circuit of the monitor etc. There is a problem that the screen is disturbed.

[0003]

In view of the above-mentioned problems, the present invention separates the sync signal from the video signal from the camera by the controller, and uses the field of this sync signal as the basis of the reference signal by the controller. Compared with the field of the signal, if there is a mismatch, stop sending one wave of the reference signal to delay the field of the camera by one field, thereby matching the field of the camera with the field of the synchronization signal of the controller and switching the camera. Is to prevent the screen of a monitor or the like from being disturbed.

[0004]

In order to solve the above-mentioned problems, the present invention provides a controller for sending a reference signal for vertical synchronization to a camera to synchronize the camera and to input a video signal from the camera. A V signal generating section for generating a signal, a V pulse generating section for generating a pulse synchronized with the vertical synchronizing signal from the synchronizing signal generating section, and a V for switching between outputting / not outputting the pulse from the V pulse generating section. A pulse control unit, a transmission cable that transmits the V pulse via the V pulse control unit to the camera and a video signal from the camera to the controller, and a sync signal from the video signal from the camera via the transmission cable. The fields of the sync signal from the sync separator and the sync signal from the sync separator and the sync signal from the sync signal generator are compared, and if the fields do not match. A camera comprising a field comparing section for outputting a signal, applying a signal from the field comparing section to the V pulse control section, and stopping the output of the V pulse from the V pulse generating section for one pulse or an odd pulse The control device of

[0005]

With the above configuration, in the camera control device according to the present invention, the controller generates the V pulse synchronized with the vertical synchronizing signal from the synchronizing signal generating section,
This V pulse is sent to each camera through a transmission cable. In each camera, a built-in synchronization signal generation circuit generates a synchronization signal synchronized with the V pulse from the controller, generates a video signal synchronized with this synchronization signal, and sends it to the controller via the transmission cable. In the controller, the sync signal is separated from the video signal from the camera, the field of this sync signal is compared with the field of the sync signal from the sync signal generator, and if they do not match, V pulse is sent as one wave or an odd wave. Stop. As a result, the field of the camera is set to 1 with respect to the sync signal of the controller.
The field is delayed and the field is the same as the field of the synchronization signal of the controller, so that the screen of the monitor or the like is not disturbed by switching the camera.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a camera control device according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a conceptual diagram of an embodiment of a camera control device according to the present invention, and FIG. 2 is a block diagram of essential parts of an embodiment of a camera control device according to the present invention. In FIG. 1, 1 is a controller and 2 ... 2n (plural) are cameras. The controller 1 generates a V pulse synchronized with the vertical sync signal from the sync signal generator and sends it to a plurality of cameras 2 ...
Further, a video signal is input, the video signal is appropriately switched, and the video signal is sent to a monitor device or the like (not shown).

In FIG. 2, reference numeral 1 is a controller and 2 to 2n.
Are cameras. Reference numeral 11 of the controller 1 is a sync signal generator, which generates a composite sync signal. 12 to 12n are camera control units, which are provided corresponding to the cameras 2 to 2n. Reference numeral 13 of the camera controller 12 is a V pulse generator, which generates a pulse synchronized with the vertical synchronizing signal from the synchronizing signal generator 11. 14 is V
The pulse control unit switches between outputting / not outputting the V pulse from the V pulse generating unit 13 based on a signal from the field comparing unit 17 described later. Reference numeral 15 denotes an input / output unit, which sends the V pulse from the V pulse control unit 14 to the camera 2 via the transmission cable 15. The transmission cable 15 transmits the video signal from the camera 2 to the camera control unit 12 simultaneously with the transmission of this V pulse. Reference numeral 17 denotes a sync separation unit, which separates the sync signal from the video signal from the camera 2 transmitted by the transmission cable 16. 18
Is a field comparator, which compares the field of the sync signal from the sync separator 17 with the field of the sync signal from the sync signal generator 11, and when two fields do not match (one is odd, the other is even) A signal is output to the V pulse control unit 14.

Next, the operation of the camera controller according to the present invention will be described. Camera control unit 12 built in the controller 1
.About.12n sends a V pulse, which is a reference signal for synchronizing the cameras 2 to 2n connected via the transmission cables 16 to 16n, to each of the cameras 2 to 2n. That is, the V pulse generator 13 of each camera controller 12-12n generates a V pulse synchronized with the vertical synchronizing signal from the synchronizing signal generator 11,
A pulse is sent from the input / output unit 15 via the V pulse control unit 14 to each camera 2 to 2n through the transmission cable 16. Camera 2-2n
Each camera control unit 12
A synchronizing signal synchronized with the V pulse of .about.12n is generated, and a video signal synchronized with this synchronizing signal is output.

The synchronization signals generated by the cameras 2 to 2n are different from those of the cameras 2 to 2n due to the rise of the respective circuits of the cameras 2 to 2n or the difference in the input timing of the V pulse to the synchronization signal processing circuit. The fields may be different from each other (odd field or even field), so that, for example, when the video signal of the odd field is output from the camera 2, the video signal of the even field is output from the camera 2n. There is.

Video signals from the cameras 2 to 2n are transmitted to the camera control units 12 to 12n via transmission cables 16 to 16n, respectively. The video signal input to the input / output unit 15 is input to the sync separation unit 17, the sync signal is separated from the video signal, and the sync signal is input to the field comparison unit 18. Field comparison unit 18
The sync signal from the sync separation unit 17
Compare with the sync signal from 11 and output the signal when the fields do not match. The match / mismatch in this field is
For example, the phases of the equivalent pulses arranged in the vertical blanking period are compared to determine the mismatch. When the field comparison unit 18 determines that the fields do not match, the signal from the field comparison unit 18 is applied to the V pulse control unit 14, and the V pulse control unit 14 receives the V from the V pulse generation unit 13 by this signal. Stop the output of one pulse or odd number of pulses.

As a result, in the camera 2, for example, as shown in FIG.
When the output of one V pulse is stopped as shown in (a), the synchronization signal 31 of the odd field is generated in synchronization with the first V pulse 21, and the even number is synchronized with the subsequent second V pulse 22. Generates the field sync signal 32 and the next third V pulse
What should have been to generate the odd field sync signal 33 in synchronism with 23, but as a result of comparing the sync signal 31 (odd field) by the field comparison section 18, it is determined that there is a field mismatch, so the second field The transmission of the V pulse 22 is stopped, and as shown in (b) of the same figure, the synchronizing signal is not generated at the timing of this V pulse 22, and the next third V pulse is generated.
Sync signal 3 of even field at the timing synchronized with 23
2'is generated, and as a result, camera 2
From the field, the video signal of the same field as the sync signal from the sync signal generator 11 is output. In the above description, the synchronization signal generation circuit 11 is described as being built in the controller 1. However, the synchronization signal generation circuit 11 may be synchronized by an external synchronization signal, and the V pulse generation unit 13 may be provided in each camera control unit 12. However, the controller 1 may be provided with only one V pulse generator, and this V pulse generator may be shared by the camera controllers 12 to 12n.

[0012]

As described above, according to the camera control device of the present invention, when the field (odd / even) of the sync signal of the video signal from the camera does not match the field of the sync signal of the controller, Since the V pulse from the controller, which is the reference of the synchronization signal generated by each camera, is stopped by sending one wave or an odd number of waves, the field of the synchronization signal generated by the camera is delayed by one field. The field of 1 corresponds to the field of the synchronization signal of the controller, and when a plurality of cameras are switched by the controller, there is almost no disturbance on the screen of the monitor or the like.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a control device for a television camera according to the present invention.

FIG. 2 is a block diagram of essential parts of an embodiment of a control device for a television camera according to the present invention.

FIG. 3 is a diagram showing a relationship between a V pulse and a synchronizing signal from the television camera for explaining the operation of the control device for the television camera according to the present invention.

[Explanation of symbols]

 1 controller 2 television camera 11 sync signal generator 12 camera controller 13 V pulse generator 14 V pulse controller 15 input / output unit 16 transmission cable 17 sync separator 18 field comparator

Claims (5)

[Claims] 1. A controller for transmitting a reference signal for vertical synchronization to a television camera to synchronize the television camera and to input a video signal from the television camera, and a synchronization signal generator for generating a composite synchronization signal. , A V pulse generator for generating a pulse synchronized with a vertical synchronizing signal from the synchronizing signal generator, a V pulse controller for switching between outputting / not outputting the pulse from the V pulse generator, and a V pulse controller A transmission cable for transmitting the V pulse to the television camera via the camera and transmitting the video signal from the television camera to the controller;
The sync separation unit that separates the sync signal from the video signal from the television camera via the transmission cable is compared with the fields of the sync signal from the sync separation unit and the sync signal from the sync signal generation unit. A television camera comprising a field comparing section for outputting a signal, wherein a signal from the field comparing section is applied to the V pulse control section, and the V pulse from the V pulse generating section is an odd pulse, and the output is stopped. Control device. 2. The television camera according to claim 1, wherein the V pulse control section stops the output of one V pulse from the V pulse generation section in response to a signal from the field comparison section. Control device. 3. A plurality of television cameras are provided, and the controller is provided with one set of the V pulse control section, the transmission cable, the sync separation section and the field comparison section, and each set is provided corresponding to each television camera. The control device for a television camera according to claim 1 or 2, wherein: 4. A plurality of television cameras are provided, and the controller is provided with the V pulse generator, V pulse controller,
The television camera control device according to claim 1 or 2, wherein a transmission cable, a sync separation unit, and a field comparison unit are provided as one set, and each set is provided so as to correspond to each television camera. 5. The V pulse generator is configured to generate a pulse synchronized with a vertical sync signal of a composite sync signal input from the outside, and the field comparator is configured to generate a pulse from the sync separator from the outside. Claim 1, Claim 2, wherein the composite sync signal and the field are compared.
The control device for a television camera according to claim 3 or 4.