JP4039926B2 - Television camera device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention has a configuration in which a camera head and a camera control unit (hereinafter referred to as CCU) are separated, and a plurality of video signals from external devices input to the camera control unit are selectively monitored by a viewfinder (hereinafter referred to as VF) of the camera head. It relates to possible television cameras.
[0002]
[Prior art]
FIG. 4 shows an example of a broadcast television camera.
[0003]
In general, a broadcasting television camera used in a studio or the like has a shape in which a camera head 24 and a CCU 33 are separated.
[0004]
A broadcast television camera needs a function that allows a cameraman to switch between the video captured by himself and the video from the other camera and display it on the VF so that the cameraman can grasp the other camera and the video currently being broadcast. . The cameraman uses the above-described function to frequently switch and monitor the return video signal, which is a return signal from the CCU, and the video signal captured by the cameraman.
[0005]
Usually, the cameraman selects and monitors a plurality of types of external video signals as the return video signals. For this reason, in general, a high-end camera device for broadcasting or the like has a plurality of external video input terminals in the CCU, and has a function of selecting this external video signal and sending it back to the camera head at the request of the cameraman from the camera head side. Have.
[0006]
A specific description will be given with reference to a configuration diagram of an example of a broadcast television camera shown in FIG.
[0007]
24 is a camera head, 33 is a CCU, 25 is a CCD, 26 is a video signal processing unit of the camera head 24, 27 is a main line / feedback signal of the camera head 24, and a plurality of external video signals input to the CCU 33 are selected. A return switch, 28 is a main line / sending signal switching switch, 29 is a VF, 30 is a transmission cable for transmitting a video signal and a control signal, 31 is a video signal processing unit of the CCU 33, and 32 is a sending signal selection switch of the CCU 33.
[0008]
The video signal obtained by subjecting the subject to photoelectric conversion by the CCD 25 is subjected to predetermined signal processing by the video signal processing unit 26. The video signal is transmitted to the CCU 33 via the transmission cable 30 (main line output).
[0009]
On the other hand, the video signal from the video signal processing unit 26 is also displayed on the main line output VF 29 via the main line / sending signal switching switch 28.
[0010]
When the return switch 27 is pressed, the main line / sending signal changeover switch 28 is controlled to switch to the return side, and the CCU 33 controls the sending back signal switch 32 to select any one of the RET_1 input, the RET_2 input, and the RET_3 input. 24 is displayed on the VF29. (Return video signal)
As described above, since the cameraman frequently monitors and monitors the return video signal and his camera video signal, it is desirable to perform this switching with as little delay as possible. However, in a normal camera device, the return video signal and the own camera video signal are switched by the camera head, and the channel switching of the return signal is performed by the CCU. Therefore, the switching of the two video signals performed by the control from the camera head side is inevitably delayed on the CCU side. For this reason, in a conventional camera device, for example, when a cameraman first looks at the return video signal of the A channel, then once looks at his camera video signal and then looks at the return video signal of the B channel, the camera head If the signal switching is made too fast, channel switching at the CCU cannot catch up, and a phenomenon occurs in which the A channel signal is displayed once and then the B channel video signal is visible (see FIG. 5). In order to avoid this, it is necessary to slow down the switching of the return signal performed by the camera head, both of which are unusable.
[0011]
[Problems to be solved by the invention]
The present invention is a television camera system composed of a camera head and a CCU. When a cameraman switches an external video signal such as a video signal currently being broadcast to another camera and the video of his camera and displays it on the VF, An object of the present invention is to prevent instantaneous display of other channel video signals while minimizing switching delay.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises a camera head and a camera control unit, and selects one of a plurality of external input video signals input to the camera control unit by a control signal from the camera head. In a television camera system comprising means for sending back to the camera head, the send-back signal, and means for selecting one of the video signal output from the camera head and outputting it to the viewfinder, the control signal causes the The control unit includes means for delaying the output timing of the return signal of the output means for a predetermined period when the return means is controlled to change the external input video signal.
[0013]
The previously selected return signal channel is memorized and compared with the stored previous channel and the selected channel. In the case of the same channel, the main signal is instantly switched to the return signal. A feature is that the video signal of the channel is counted for a time to avoid display for a moment and delayed, and then a means for switching from the main line to the return signal is provided.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram of an embodiment of a television camera apparatus showing a first embodiment of the present invention. The specific operation will be described in detail below.
[0015]
1 is a camera head, 2 is a CCD, 3 is an A / D converter, 4 is a digital signal processing unit, 5 is a D / A converter, 6 is a main line / feedback signal of the camera head 1, and is input to the CCU 17. A return switch for selecting a plurality of external video signals, 7 is a main line / return switching control device for the camera head 1, 8 is a main line / return signal switching switch, 9 is a VF, 10 is a D / A converter, 11 is a DATA_MIX circuit, Reference numeral 12 denotes a transmission cable, 13 denotes a CCU, 14 denotes a CPU data separation circuit, 15 denotes a return signal selection switch, and 16 denotes a CPU.
[0016]
First, the video signal output (main line output) of the camera head 1 will be described.
The analog video signal obtained by subjecting the subject to photoelectric conversion by the CCD 2 is converted to a digital video signal by the A / D converter 3.
[0017]
The digital video signal is subjected to predetermined signal processing by a digital signal processing unit 4.
[0018]
The processed digital video signal is divided into a signal transmitted and output to the CCU 13 side and a signal to be displayed on the VF9.
[0019]
The signal transmitted to the CCU 13 is output from the main line / return switching control device 7 and added to the digital video signal processed by the DATA_MIX circuit 11 and added to the digital video signal that is information such as channel selection of the return signal and transmitted to the CCU 13. Then, the CCU 13 outputs a main line video signal video signal.
[0020]
A signal to be displayed on the VF 9 is converted to an analog video signal by the D / A converter 5 after the processed digital video signal, and is displayed on the VF 9 through the main line / sending signal changeover switch 8.
[0021]
The return signal output from the CCU 13 separates the CPU signal including the channel information of the return signal added to the digital video signal transmitted from the camera head 1 by the CPU data separation circuit 14, and the CPU 16 returns the information according to the information. By operating the signal selection switch 15, any one of the RET_A input, the RET_B input, and the RET_C input input from the outside is selected.
[0022]
The selected digital video signal is transmitted from the CCU to the camera head 1 via the cable 12. This video signal is converted into an analog video signal by the D / A converter 10, and the return video signal is displayed on the VF 9 via the main line / send back signal switching switch 8.
[0023]
Here, the switching operation of the main line / return signal changeover switch 8 will be described in detail with reference to FIG.
[0024]
As described in the prior art, the return signal is switched on the CCU 13 side, and the main video signal and the return video signal are switched on the camera head 1 side. Since these switching controls are performed by the control from the camera head 1, the return signal channel switching on the CCU 13 side is delayed.
[0025]
For this reason, when a return signal different from the previously selected channel is selected, switching between the return video signal and the main line video signal on the camera head 1 side is delayed in order to avoid instantaneous display of the return video signal selected last time. To do.
[0026]
FIG. 2 is a block diagram showing a signal flow until the switching information reaches the main line / sending signal switching switch 8 when the return switch 6 is pressed.
[0027]
When the return switch 6 is pressed, the selected channel information 18 ′ is stored in the selected channel information storage unit 18 of the storage device 20 such as a memory. The previously selected channel storage unit 19 stores previously selected channel information 19 ′ selected last time. The information in the selected channel information storage unit 18 is updated and stored in the preselected channel storage unit 19 only when the information is different from the information in the selected channel information storage unit 18.
[0028]
The channel comparison device 21 compares the information of the selected channel information 18 ′ and the information of the previously selected channel information 19 ′. If the channel information matches, the channel comparison device 21 switches from the main / return switching control circuit 23 to the main / return signal switching switch 8. The signal is output, the main line is switched to the return signal, and the return video signal is output. When the channel information is different, the switching information is output from the main line / return switching control circuit 23 to the counter 22 in order to delay switching for a time during which the instantaneous display of the return signal selected last time can be avoided. After a predetermined period of delay in the counter 22, a switching signal is output to the main line / sending signal switching switch 8 and the main signal is switched to the return signal.
[0029]
The above signal flow will be described with reference to the diagram showing the time relationship in FIG.
FIG. 3A shows the time relationship when the same channel as the previously displayed return signal is selected, and FIG. 3B shows the time relationship when a different channel return signal is selected.
[0030]
In FIG. 3 (A), when the same channel is selected and the return switch 6 is turned ON at time {circle around (1)}, the main line / sending signal changeover switch 8 is switched to the sending back signal side at time {circle around (2)}. The channel return signal is displayed. Since the return signal selection switch 15 in the CCU 13 again selects the same channel as the previous time according to the channel information of the return signal transmitted from the camera head 1 at time {circle around (3)}, no switching shock occurs. In addition, the return signal can be instantaneously displayed on the VF 9 from the main line signal.
[0031]
3B, when a different channel is selected and the return switch 6 is turned on at time {circle around (1)}, channel information of the return signal is transmitted to the return signal selection switch 15 in the CCU 13, and at the same time, the camera head 1 The counter 22 counts the time until switching from the main line signal to the return signal, and delays the main line / send back signal switching.
[0032]
By switching the return signal from channel_A to channel_B at time {circle around (5)}, the signal returned from channel_B is sent back from the CCU 13 to the camera head 1 (HEAD). Here, by switching the HEAD side main line / sending signal changeover switch 8 at time {circle around (6)} where it is possible to avoid displaying the sending signal of the previous channel for a moment, the sending signal of channel_B is displayed on VF9. Is done.
[0033]
By doing in this way, it becomes possible to display on the VF9 without displaying the return signal of the previous selection channel for a moment.
[0034]
As described above, when the same channel as the previously selected channel is selected, the present invention instantaneously switches from the main line to the return signal, and when a different signal is selected, the return signal of the previous selected channel is displayed momentarily. Therefore, it is possible to switch between the main video signal and the return video signal, and it is possible to provide a television system with excellent operability that does not cause a shock even if the main video signal and the return video signal are switched.
[0035]
【The invention's effect】
With the present invention, when a cameraman displays an external video (feedback video) such as a video from another camera or a currently broadcast video on the VF by switching to a picture of his camera with a simple configuration, Video disturbance will not occur.
[0036]
As described above, when the present invention is used, it is possible to realize a television camera device that does not cause a switching shock while minimizing a switching delay when switching between a main line video and a return video signal as compared with the prior art. The operability can be greatly improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing the configuration of a first embodiment of the present invention.
FIG. 2 is a block diagram showing main line / sending signal switching control according to the present invention. FIG. 3 is a diagram illustrating the phase and signal content of each input / output video signal according to the present invention. FIG. 5 is a diagram for explaining the display of the main line signal and the return signal on the VF when using the prior art. FIG. 6 is a diagram on the VF of the main line signal and the return signal when using the present invention. Diagram explaining the display on the screen [Explanation of symbols]
1. Camera head, 2. CCD, 3. 3. A / D converter, 4. Digital signal processing unit D / A converter, 6. 6. Return switch, Main line / return switching control device8. Main line / sending signal changeover switch, 9. VF, 10. D / A converter 11. DATA_MIX circuit, 12. Transmission cable, 13. CCU 14, CPU data separation circuit 15, return signal selection switch 16. CPU
18. 18. Selected channel information storage unit, Pre-selected channel information storage unit, 20. Storage device, 21. Channel comparison device, 22. Switching delay counter, 23. Main / return switching control circuit, 24. Camera head, 25. CCD, 26. Video signal processing unit 27. Return switch, 28. Main / return switch 29. VF30. Transmission cable 31. Video signal processing section, 32. Send back signal selection switch 33. CCU

Claims (1)

Means comprising a camera head and a camera control unit, selecting one from a plurality of external input video signals input to the camera control unit by a control signal from the camera head and sending it back to the camera head; In a television camera system having output selection means for selecting any one of the video signal outputs of the camera head and outputting it to a viewfinder, the external input video signal is changed to the return means by the control signal. A television camera device comprising control means for delaying the output timing of the return signal of the output selection means for a predetermined period when controlled.

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