JPH023590B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION There are various control and adjustment items required for a television camera, as listed below.

(i) White balance adjustment (ii) Automatic aperture control (iii) When shooting while switching between multiple cameras, adjust the following items to external reference signals to adjust for variations between each camera. Adjustment (a) Subcarrier phase (b) Synchronization signal phase (c) Brightness level (d) Chroma level (e) Pedestal level, etc. The above are items that require continuous (analog) control and adjustment. , as digital adjustment and control items such as on/off (iv) command control of lens close (v) on/off control of color barge generator (vi) automatic gain control ( (vii) command control that forcibly increases the gain when AGC) is no longer applied; and (vii) on/off control of tally lamps.

As mentioned above, television cameras have a large number of control and adjustment items, and it is conceivable to be able to control all of them electronically.

Therefore, the television camera was replaced with a camera head unit (hereinafter referred to as
CHU) and a camera control unit (hereinafter referred to as CUU) that controls this CHU, and the CCU creates control and adjustment data.
This is used as CHU during the vertical blanking period of the video signal.
On the other hand, a microcomputer is installed on the CHU side, and this microcomputer processes the data transmitted from the CCU side.
A new device has been devised to provide each adjustment and control.

In this case, the data created by the CCU and transmitted to the CHU is digital serial data in order to be able to transmit data for a large number of items over a single transmission line.

Figure 2 shows an example of serial data for one item, which consists of a start signal with two or more consecutive high potentials, a subsequent four-bit identification code, and a subsequent three-bit identification code. It consists of an address code followed by a 9-bit data code. The identification code is used to distinguish between analog adjustment and control items and digital adjustment and control items, and the address code is used to identify each adjustment and control item such as chroma level and brightness level. The code is the content of each adjustment and control data. Note that the data code is expanded or contracted as necessary.

Then, serial data for each item is sequentially transmitted from the CCU to the CHU for the number of items mentioned above during the vertical blanking period.
Normally, all items are transmitted sequentially regardless of whether or not each control data and adjustment data has changed. Therefore, when there are many adjustment and control items as described above, there is a problem in that a considerably high speed data transmission is required.

The present invention seeks to provide a novel television camera that takes this point into particular consideration.

Hereinafter, an example of a television camera according to the present invention will be explained with reference to the drawings.

In FIG. 1, 10 is a CCU, and 20 is a CHU, each having microcomputers 11 and 21. The microcomputer 11 has a central processing unit 12, a ROM 13, a RAM 14, input/output ports 15a, 15b, 15c, 15d,
15e and 15f. The microcomputer 21 also has a central processing unit 22 and a ROM 2.
3, RAM 24, and input/output ports 25a, 25
b, 25c, and 25d.

Further, the CCU 10 is provided with the data setting operation unit 16 for the analog adjustment and control items described above. This operation section 16 is set by volumes VR ₁ , VR ₂ . . . _{VR n} for data setting for each item, and when analog voltage data AIN ₁ , AIN ₂ . It's summery. That is, data AIN ₁ , AIN _{2 . .} . is sent from the selector 16s in a time-division manner by a select signal from the port 15d of the microcomputer 11.
AIN _n are obtained sequentially. In other words, analog data AIN ₁ , AIN ₂ . . . AIN _n are sequentially scanned.

Then, the voltage obtained from the selector 16s is A-D converted and digitized by a combination of a comparator 16A and a D-A converter 16C according to a program of the microcomputer 11, which will be described later. The information is stored at the address corresponding to each item.

Further, the CCU 10 is further provided with the data setting operation unit 17 for the digital adjustment and control items described above. This has switches SW ₁ , SW ₂ . . . SW _o for setting data for each item. Then, digital data DIN ₁ , DIN ₂ ...DIN _o of "0" and "1" according to the state of the switch for each item is stored in the RAM 14.
The data is stored at the corresponding address.

The CCU 10 is also provided with a lock switch 18. When this switch 18 is turned on, even if the operation parts 16 and 17 are operated,
This is to prevent the adjustment data and control data stored in the RAM 14 from being changed, and to prevent erroneous operations. Information as to whether the lock switch 18 is on or off is supplied to the microcomputer 11 through the port 15f.

And the digital data of each item is CCU10
The data is converted into serial data as described above, transmitted to the CHU 20 via the transmission line 1, inputted to the port 25a of the microcomputer 21,
Loading is done. Here, reading of serial data in the microcomputer 21 is performed by interrupt processing.

In this way, the serial data read into the microcomputer 21 is decoded by the identification code and address code, and each is temporarily stored at a corresponding predetermined address in the RAM 24.

Then, the digital information of the voltage data set by the operation unit 16 of the CCU 10 is taken out from the port 25b, converted back to an analog DC voltage by the DA converter 26C, and supplied to the selector 26s. In addition, a select signal is obtained from the port 25c, and the selector 26s is controlled by this selector signal, and information on the voltage set at the volume VR ₁ is sent to the sample hold circuit 27 ₁ , and the voltage set at the volume VR ₂ is transmitted to the sample hold circuit 27 1. The information on the voltage set by the volume VR _n is held in the sample and hold _circuit 27 ₂ respectively.

The operation of reading data from the RAM 24 and sample-holding the read data in the sample-and-hold circuits 27 ₁ , 27 _{2 .} . . 27 _n is always performed during the vertical blanking period.

On the other hand, digital information set on the operation unit 17 of the CCU 10 is read out from the RAM 24 and obtained from the port 25d.

Then, sample and hold circuits 27 ₁ , 27 ₂ . . .
Analog adjustment and control voltages from port _27n and digital control signals from port 25d are supplied to each adjustment section and control section of the camera, respectively.
That is, 28 is an image pickup tube, and an image is formed on this image pickup tube by incident light through an aperture 28I and a lens system 28L, and an image signal is obtained from this image pickup tube 28. This imaging signal is supplied to the video process amplifier 29 and converted into an NTSC color video signal.
This is supplied to the monitor receiver 30 through the transmission line 2, and the image taken by the camera is reproduced.
The analog adjustment and control voltages and digital control signals described above are then supplied to the video process amplifier 29 to perform various adjustments and controls.For example, if the volume VR ₁ is for aperture adjustment, the sample and hold circuit 27 The output voltage of ₁ is supplied to, for example, a DC motor that moves an aperture plate to adjust the aperture.

Note that the output of the video process amplifier 29 is supplied to the monitor receiver 30 through the transmission line 2, and the image captured by the camera is reproduced. Therefore, various adjustments and controls are made while viewing the reproduced image on the monitor 30. In this case, CHU20 and
All of the signal lines and power supply lines to and from the CCU 10 are combined into one cable and connected together using a multi-pin connector. Therefore, the output video signal of the video process amplifier 29 is once supplied to the monitor receiver 30 through the CCU 10.

As described above, the serial data is transmitted from the CCU 10 to the CHU 20. In the present invention, after turning on the power and transmitting all the serial data for each urgent adjustment and control item to the CHU 20, The serial data is transmitted to the CHU 20 only when the setting is changed in the operation unit 16 or 17 and changed from the previous data.

The above operation is performed by microcomputer 1.
This is carried out according to the program written in the ROM 13 of No. 1.

That is, FIG. 3 shows a flowchart of the program stored in the ROM 13.

In step 100, the program is started by turning on the power of the camera.

Next, in step 101, the analog data
The cutoff value of AIN _i (i=1, 2...m) is set. That is, first, the volume VR ₁ of the operation section 16 is
The voltage value AIN ₁ set by selector 16
s, and as will be described later, the comparator 16A and the D-A converter 16 are
A digital signal DAIN ₁ is generated by C, and this is written to the corresponding address of the RAM 14. Then voltage AIN ₂ set by volume VR ₂
is converted into a digital signal DAIN ₂ by the comparator 16A and the DA converter 16C, and this is written into the corresponding address of the RAM 14. Below, in the same way, sequentially increase the volume VR ₃ ~
Digital signals DAIN ₃ to _{DAIN n} of voltage data AIN ₃ to AIN _n set at VR _n are written to each corresponding address of the RAM 14 . At the same time, these digital signals are converted into serial data as described above and sequentially transmitted to the CHU 20.

The above-mentioned A-D conversion operation is performed as follows.

First, digital information corresponding to 1/2 of the maximum analog voltage is read from the RAM 14, obtained from the port 15b, and transferred to the D-A converter 16C.
The analog voltage E is set to ₁ , and this analog voltage
E ₁ and data AIN _i are compared by comparator 16A,
Comparator 1 when data AIN _i is greater than voltage E ₁
The output of 6A is negative, and when it is small, it is positive.

When the output of comparator 16A is negative, port 15b
Digital information with a voltage higher than voltage _E1 by 1/4 of the maximum analog voltage is obtained, which is converted to analog voltage AE ₂ by the D-A converter 16C, and this analog voltage AE ₂ and data AIN _i are compared. Ru.

When the output of comparator 16A is positive, port 15b
Digital information with a voltage lower than voltage _E1 by 1/4 of the maximum analog voltage is obtained, which is converted into analog voltage _LE2 by the DA converter 16C, and this analog voltage _LE2 and data AIN _i are connected to the comparator. 16A
It is compared in.

Hereinafter, when the number of comparisons of the comparator 16A is ⁿ , the comparator When the output of 16A is negative, a high voltage is obtained from port 15b, and when it is positive, a low voltage is obtained from port 15b, and both inputs are compared in comparator 16A. When both inputs become equal, the output of comparator 16A becomes "0".
When this happens, the above operation stops and the digital information obtained at the port 15b at that time is obtained as the digital signal DAIN _i of AIN _i .

Next, in step 102, digital control data DIN _j (j=1, 2...n) is initialized. That is, "1" or "0" data set by the switches SW ₁ , _{SW 2} . transmitted.

Next, in step 103, it is determined whether the lock switch 18 is on or off, and if it is on, the process stops at step 103.

If the lock switch 18 is off, the process proceeds to the next step 201.

From this step 201 to step 20
Up to 8 are the analog data setting operation section 16,
Detects whether the data has been newly set for any item, rewrites only the data of the changed item in RAM 14, and CHU 20
Steps 202 to 208 are repeated for each item starting from data AIN ₁ .

That is, step 202 is a step in which the i-item data AIN _i from the selector 16s is A-D converted into a digital signal DINN _i as described above.

In the next step 203, this digital signal is
Error Δ between DAIN _i and digital data MAIN _i of item i previously stored in RAM 14 = DAIN _i
−MAIN _i is calculated.

In the next step 204, a value α that takes into account errors due to changes in volume temperature, etc. is compared with the absolute value 〓Δ〓 of the error Δ, and when |Δ|<α, it is assumed that the set value has not changed. Step 2
The process advances to step 07, and when |Δ|≦α, it is determined that the set value has been changed, and the process advances to step 205.

In step 205, the digital signal DAIN _i of the i-th item is stored in the RAM 14 instead of the previous data.
be rewritten as .

Then, in the next step 206, the serial data of this digital signal DAIN _i is transferred from CCU10 to CHU
20.

Step 207 is a step for proceeding to the next (i+1)th step.

Step 208 is a step to determine whether the calculation process has been completed up to the m-th item. If the m-th item has not been reached, the process returns to step 202, and when the m-th item has been reached, the process proceeds to the next step 301. Proceed to.

From step 301 to step 307, the digital data setting operation unit 17 detects whether or not to re-set data for any new item, and only changes the data for the changed item.
In the step of rewriting the data in the RAM 14 and transmitting it to the CHU 20 side, steps 302 to 307 are repeated for each item in order from data DIN ₁ .

That is, in step 302, data DIN _j of the jth item is read.

Next, in step 303, the data MDIN _j of the jth item previously stored in the RAM 14,
It is determined whether the read data DIN _j is different. If the data is not different from the previous data MDIN _j , that is, if the data has not changed, the process advances to step 306. previous data
If MDIN _j has changed, proceed to the next step 3.
Proceed to 04.

In step 304, the changed data DIN _j
is written to RAM 14 in place of the previous data.

Then, in step 305, this data DIN _j
is transmitted to the CHU 20.

Step 306 is a step that advances the item to the next one.

Step 307 is a step to determine whether the calculation process has been completed up to the last nth item. If the nth item has not been reached, the process returns to step 302, and if the nth item has been processed, the process returns to step 103. .

Thereafter, steps 103 to 307 are repeated.

In this way, only the serial data of the items that have been reconfigured using the operation units 16 and 17 are transmitted to the CHU 20 during the vertical blanking period of the video signal, and the CHU
At 20, the serial data is decoded by the microcomputer 21, and the contents of the corresponding address in the RAM 24 are rewritten with the new data.

Therefore, the sample hold circuit 27 ₁ , 2
The contents of the corresponding items of 7 ₂ ...27 _n are changed, the contents of the corresponding digital data from the port 25d are changed, and the adjustment and control status of that item is changed.

As described above, in the present invention, a microcomputer is also provided on the CCU side, and this detects an item whose data changes when the operation units 16 and 17 are operated, and only then transfers the data of that item to the CHU side. As a result, the following remarkable effects can be achieved.

That is, the transmission speed of serial data from the CCU to the CHU can be relatively low. Therefore, a low-speed transmission line for transmitting serial data is sufficient, and the transmission cost is reduced. Furthermore, the programs of the microcomputers 11 and 21 can generate and read serial data.

It is also effective when analog data AIN _i is A-D converted and transmitted. That is, A-D
During the process of conversion, even if the position of the analog voltage setting volume is constant, the A-
There is a risk that the A-D conversion value may change each time it is read into a computer due to quantization errors in the D converter, noise generated by the volume itself, and disturbance noise. For this reason, if A-D conversion data is transmitted to the CHU as serial data every time it is read into a computer as in the past, regardless of whether there is a change in the data, data fluctuations due to quantization errors and noise can be adjusted and controlled as is. This appears in the data, causing a phase error in the reproduced video signal and fluctuations in the video level, which has an adverse effect.

In contrast, in the present invention, data is transmitted to the CHU only when there is a change in data that is greater than the amount that takes into account these errors and noises, that is, when the position of the volume is changed and the data is changed. When the position of the volume does not change, the previous data stored in the RAM 24 is used as adjustment and control data, so that the above-mentioned adverse effect on the video signal does not occur.

In addition, in the example shown in the figure, the CCU 10 is provided with a lock switch 18, and when this switch 18 is turned on, reading of data from each operation section 16 and 17 is stopped.
If this switch is turned on, the control data and adjustment data will not change even if a person other than the person in charge of operating the camera carelessly touches the operating sections 16 and 17 when the person in charge of operating the camera leaves the camera. Therefore, erroneous operations can be prevented.

[Brief explanation of drawings]

Fig. 1 is a system diagram of an example of a television camera according to the present invention, Fig. 2 is a diagram for explaining an example of the state of transmitted data, and Fig. 3 is a flowchart showing an example of a program of a computer on the CCU side. . 10 is CCU, 11 is microcomputer,
12 is its central processing unit, 13 is its ROM, 1
4 is its RAM, 16 is an analog data setting operation section, 17 is a digital data setting operation section, 18
is a lock switch, 20 is a CHU, 21 is a microcomputer, 22 is its central processing unit, 23
is its ROM, 24 is its RAM, 28 is the image pickup tube,
29 is a video process amplifier.

Claims (1)

[Scope of Claims] 1. A camera head unit comprising a camera head unit and a camera control unit, wherein the camera head unit includes a first computer having a first central processing unit and a first memory; are each provided with a second computer having a second central processing unit and a second memory, and in the camera control unit, analog data of a plurality of adjustment items and control items is created, and the analog data is Digital data is obtained through A-D conversion, and each digital data is stored in the second memory, transmitted to the camera head unit, stored in the first memory, and read from the first memory. Various adjustments and controls are performed using the read digital data, and writing of the digital data to the second memory and transmission to the camera head unit are performed at the same time as the above creation. The television camera is configured to detect only when a change greater than a set value occurs when comparing digital data obtained by D conversion with previous digital data stored in the second memory. 2. The television camera according to claim 1 is provided with a lock switch, and information on whether the switch is on or off is input to the second computer, and when the lock switch is turned on or off, the data is A television camera configured to stop reading data to the second computer.