JPS58171185A - Auto-registration system of color television - Google Patents

Abstract

PURPOSE:To adjust registration precisely and automatically by logically operating a level difference signal and an edge signal from two channels to obtain a discrimination signal indicating the shift direction of registration. CONSTITUTION:Video signals from G and R channels are binary-coded by binary-coding circuits 8, 9 and the binary-coded signals are inputted to a comparator 18 to output a level difference signal E. Edge signal generating circuits 19, 20 generate edge signals Ge, Re. These edge signals Ge, Re are inputted to an operation circuit 21 and a discrimination signal indicating the shift direction of registration is outputted from the operation circuit 21. The discrimination signal is applied to registration compensating devices 15, 16 through a control circuit 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for automatically performing registration adjustment for a color television camera.

Color television imaging devices are widely equipped with multiple image pickup elements, such as image pickup tubes, with different spectral sensitivity characteristics, and which combine video signals from these multiple image pickup tubes to obtain a color video signal. However, in this type of imaging device, it is necessary to accurately perform so-called registration, which is the superimposition of images using video signals from the respective imaging tubes.

This registration is performed by adjusting the size to match the scanning range of the optical system to be imaged, correcting geometric distortion caused by variations in the imaging optical system and imaging element system, and adjusting the centering to match the relative position of the scanning range. However, as a method for adjusting this registration, a manual method as shown in FIG. 1 has conventionally been mainly adopted.

In the figure, 1 is a G (green) channel imaging system, 2 is an R (red) channel imaging system, 3 is a B (blue) channel imaging system, 4 is a viewfinder (or monitor),
2v, 3v are knobs for adjusting the registration, and the operator can use the knobs 2v, 3. Manipulate r so that the R and B images match based on the G image.
CIIl was in order.

Therefore, this method has the disadvantage that the operation is complicated and requires a considerable amount of adjustment time.

In particular, this type of registration is likely to shift when the usage conditions of the television camera change, and in particular, large shifts occur due to changes in ambient temperature, requiring readjustment frequently during use. Manual methods do not allow for sufficient adjustment, making it difficult to obtain visual signals with excellent image quality. ! There was no F.

In order to solve this problem, a so-called auto-registration device that automatically performs registration adjustment when necessary has been proposed and widely adopted.

Such an auto-registration device! An example of
As shown in the figure.

In the figure, 1 to 3 are the same mfs for each channel as in Figure 1.
ll series, 5 is a test pattern for registration,
6 and 7 are preprocessing circuits, 8 and 9 are binarization circuits, 10.11
12 is an intermediate processing circuit, 12 is a pulse comparator, 13 is a post-processing circuit, 14 is a control circuit, 15.16 is a registration correction device 2, and 17 is a changeover switch.

The test pattern 5 is included in the imaging optical system for the three imaging systems 1 to 3, and the pattern is imaged on the imaging surface of each of the imaging systems 1 to 3 only during registration adjustment.

The preprocessing circuits 6 and 7 are circuits that perform signal processing such as nonlinear amplification and signal clamping (to ensure binarization).

The binarization circuits 8 and 9 convert between "0" and "1" depending on the signal level.
” signal is output.

Intermediate processing circuits 10 and 11 are circuits that perform arithmetic processing necessary for pulse comparison.

The pulse comparator 12 compares the input pulses between each channel, detects the pulse interval, and outputs a signal representing the registration deviation.

The post-processing circuit 13 functions to perform processing such as checking for errors.

The control circuit 14 sends an @ control signal to the registration correction at15 or 16 in response to a signal representing a registration deviation, and operates to match the registration of the imaging system 2 or 3 with the imaging system 1 of the G channel. The circuit may be configured by a microcomputer or the like.

The switch 17 is a switch for switching between the registration adjustment of the B channel and the B channel.

Next, to explain the operation, when adjusting the registration, test pattern 5 is inserted into the optical path of the damaged optical system, and the resulting pattern is adjusted to the W11 value of the imaging systems 1 to 3 of each channel. Form an image.

As a result, the image (# signal) based on the test pattern 5 obtained from the G channel imaging system 1 passes through the preprocessing circuit 6
An image signal that has been manually inputted to the value converting circuit 8 and shaped into a pulse is supplied to the pulse comparator 12 via the intermediate processing circuit 10.

On the other hand, for example, if the switch 17 is switched to the R channel side as shown in the figure, the image signal of the test pattern 5 from the R channel imaging system 2 will be transmitted to the preprocessing circuit 7.
The signal is shaped into a pulse via the binarization circuit 9 and the intermediate processing circuit 11, and is supplied to the pulse comparator 12 in the same manner as the G channel signal.

Then, the deviation between the pulsed signals supplied to the pulse comparator 12 corresponds to the deviation of the image signal between the G channel imaging system 1 and the R channel imaging system 2. Therefore, the control circuit 14 takes in the signal from the pulse comparator 12 via the post-processing circuit 13, and adjusts the R channel registration correction device fl 15 accordingly.
By changing the VC supply h [l signal and setting it to 5 so that the pulsed signal from the R channel input to the pulse comparator 12 matches the pulsed signal of the G channel, the B Channel registration adjustment is performed automatically.

Next, when the switch 17 is switched to the B channel, the control signal for the B channel registration correction device 16#C changes in the same way, and the registration adjustment of the B channel with respect to the G channel is automatically performed. . Incidentally, if a microcomputer is used as the control circuit 14, all of the above operations can be performed by a program of the microcomputer.

Therefore, according to the auto-registration device shown in Fig. 2, it is possible to easily readjust the registration in a short time when necessary, and the image quality is excellent with accurate registration always maintained. You can get a color television signal.

However, the auto-registration device f of the method shown in FIG. The purpose of this is to eliminate the shortcomings of the prior art described above and to develop an auto-registration storage method that automatically performs accurate registration adjustments while imaging a general subject without using a test pattern. It is on offer.

To achieve this objective, the present invention extracts a level difference signal representing a predetermined level difference between video signal signals from two channels to be registered, and respective edge signals of these video signal signals. The present invention is characterized in that the level difference signal and the edge signal are logically operated to obtain a discrimination signal representing the direction of registration deviation, and the registration correction device is controlled in accordance with this discrimination signal. .

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of autoregistration according to the present invention will be described with reference to the drawings.

FIG. 3 shows an embodiment of the present invention, in which the same or equivalent parts as in the conventional example shown in FIG. 2 are given the same reference numerals, and detailed explanations thereof are omitted.

The switch 17 has a two-circuit, two-contact configuration instead of a one-circuit, two-contact configuration, and the other interlocked switch is represented by 11.

The comparator 18 converts the G-channel Eirin signal from the preprocessing circuit 6 into a binarized signal G, which is processed by the binarization circuit 8, and the R or B channel Eirin signal from the preprocessing circuit 7 into the binarized circuit 9. extracts only the portion where the level difference with the binarized signal RorB processed by is equal to or greater than a predetermined value
Since the circuit generates a window comparator or the input signals G and RorB are binarized, it can be thought of as an exclusive OR circuit.

The edge signal generation circuits 19 and 20 are circuits that extract the edge portions of the binary video signals G and RorB (hereinafter, RorB is referred to as X) and output edge signals Ge and Xe. It consists of a circuit.

The arithmetic circuit 21 receives the level difference signal E and the edge signals Ge, Xe.
As an input, an operation is performed according to one of the following three types of logic, ■, , and O, and two types of discrimination signals Y are obtained.
, z. In the case of logic ■, it consists of, for example, four AND circuits, one inverter, and two OR circuits, and in the case of logic ◎, it consists of, for example, two AND circuits. In the case of logic 0, it is composed of, for example, four 3-man power AND circuits, a 3s inverter, and two OR circuits, or one 3-man power 8-output decoder and two OR circuits. It is something.

The switch 1γ is used to switch control signals for the B channel and the B channel registration correction devices 15 and 16 in conjunction with the switching operation of the switch 17.

Next, the operation of this embodiment will be explained with reference to timing charts shown in FIGS. 4 to 6.

Of these timing charts, FIG. 4 shows the case where the arithmetic circuit 21 is configured to perform calculations according to logic, FIG. 5 shows logic (B) I'm, and FIG. 6 shows logic (B) I'm. Although the cases shown in ◎ are shown, similar operations can be obtained in each case, so they will be explained together in the following explanation.

First, assume that the switches 17, 17' are switched to the R channel as shown.

Then, the video signal from the imaging system 2 of the channel is converted into a 2g signal at the output of the binarization circuit 9 as shown in Figs. 4, 5, and 6 (hereinafter simply referred to as figures). It is processed by the edge signal generation circuit 20, and the edge signal Re of the R channel appears at its output as shown in FIG.

On the other hand, regardless of the switching state of the switches 17 and 1γ, the 2
At the output of the digitizing circuit 8, a signal G obtained by binarizing the video signal from the G channel imaging system 1 appears at 5 as shown in FIG. 4, which is processed by the edge signal generating circuit 19. The edge signal Ge of the G channel appears at its output as shown in the figure.

At the same time, the signals G and R obtained by binarizing the G channel and R channel Eirin signals, which are the outputs of the binarization circuits 8 and 9, are also input to the comparator 18, and these signals G and the ordinary level are input to the comparator 18. An output signal generated only when there is a difference greater than a predetermined value, that is, a level difference signal E, is extracted as shown in the figure.

Therefore, these edge signals Qe and Re and the level difference signal E are supplied to the arithmetic circuit 21, and the above three
The arithmetic processing according to one of the types of logic is performed, and the two types of discrimination signals Y and Z are respectively shown in the figure (Logic ■ is shown in Figure 4, logic ◎ is shown in Figure 5, logic ◎ is shown in Figure 6). Figure) is taken out and supplied to the control circuit 14. At this time, the discrimination signals Y and Z are R for the G channel.
The control circuit 14 uses the discrimination signals Y and Z to indicate the direction of misregistration of the channel.
A control signal is generated in accordance with the signal, and is supplied to the registration correction device 15 via the switch 1τ to change the deflection characteristics of the R channel imaging system 2 to match that of the G channel. Automatically correct deviations.

After completing the registration adjustment of the R channel to the G channel, turn switch 17.1γ to the third position.
If the switch is made in the opposite direction to that shown in the figure, that is, to the B channel, the registration adjustment of the B channel with respect to the KGG channel is performed in the same manner as in the case of the R channel described above, and the registration adjustment is completed.

Next, the registration signal ytn is determined by the discrimination signals Y and Z.
The i'' h, tn determination operation will be explained in more detail depending on the state of registration deviation.

First, we will explain centering adjustment in registration.

(1) to (6) in the figure are reference channels, that is, G
This is a case where the compared channel that should be centered with respect to the channel, for example, the R channel, is shifted, and in the figure (11 and (2)), the levels of the video signals of the G channel and the R channel are almost equal, (3) and (4) show when the respective binarized signals G and the general pulse width are equal, the level of the R channel video signal is lower than the G channel video signal, and the binary signal G is equal to the normal pulse width. If the converted signal G has a wider impulse than R, then the R channel video signal has a higher level than the G channel video signal, and the binarized signal The graphs show cases in which the normal pulse width is wider than G; in either case, the number of pulses Yn of the discrimination signal Y and the number of pulses Zn of the judgment signal Z are not equal. When the R channel shifts to the right on the monitor screen, that is, when (1), (3), or (5) in the figure, Y
n) Zn, and on the contrary, when it shifts to the left, that is, (2L (4), (6) in the figure), Y
It becomes n.

In addition, (7) and (8) in the figure are R for G channel.
If the channels match, (7) is G.
The level of the Eirin signal on the channel was higher than the R channel! , (8) shows the case when the level of the Eirin signal of the opposite KGG channel and the R channel was louder, but in any case, the number of pulses Yn and Zn appearing as the discrimination signals Y and Z are as follows. , Y n =
It becomes Z n.

Therefore, the control circuit 14 receives the discrimination signal Y from the arithmetic circuit 21.
Input Z and compare the pulses Yn and Zn to find Y n
) Generates opposite control signals when Z n and Yn (Zntj'/3), and sends the signals to switch 1γ.
is supplied to the centering correction device 15 via the centering correction device 15. As a result, the scanning range of the R channel imaging system 2 is changed, and when Y n ) Z n , the signal is controlled to move to the left;
If control is performed to move the signal R to the right when n, so that Yn=Zn, it is possible to automatically adjust the centering of the R channel with respect to the G channel.

Note that Figures (7) and (8) only show cases where there is a level difference between the G channel and R channel Eirin signals, and therefore the pulse widths of the signals G and B are different. If the video signal levels of the channels are equal and the signal G and the average pulse width are equal, the level difference signal E will be "0", so the edge signals Ge and Re are directly calculated as the discrimination signals Y and Z. from the circuit 21 and therefore also in this case Y n −
Needless to say, the discrimination condition Zn, which indicates matching of centering, is maintained.

When the centering adjustment of the R channel with respect to the G channel is completed in this way, switch 17.1'f
If the channel is switched to the B channel side, the centering adjustment of the B channel relative to the KGG channel is automatically performed in exactly the same way as in the case of the R channel described above, and the centering adjustment is completed.

Although the figure shows only a part of the video signal of each channel, in reality, only a predetermined range of video signals including the center of the image is extracted from the video signals from each imaging system 1 to 3. Centering may be determined.

Above, we have explained the centering adjustment, which is part of the registration adjustment, but if you select the extraction range of the Eirin signal in one part of the periphery of the image plane and reduce the selected range,
Since deviations due to size, linearity, distortion, etc. can be regarded as uniform deviations, it is possible to automatically adjust deviations in size, linearity, distortion, etc. in the same way as the centering adjustment described above. It can be done automatically.

Further, at this time, it goes without saying that the video signals from each of the imaging systems 1 to 3 may be from any subject, but it is most desirable that the video signals be from a subject containing a large amount of white and black.

By the way, in the above embodiment, Fig. (9), C11
As shown in Fig.
Even when one of the video signals is not obtained as shown in t+ and aa, the discrimination signals Y and Z are obtained, except in the case where the logic I'Bl is negative, that is, in the case of 00, 0 in FIG. The number of pulses Yn and the number of pulses Zn are equal, making it impossible to distinguish (Ql in Fig. 5), but α would result in a false judgment).As explained above, this auto-registration method is applied. The reason for this is to correct registration deviations due to K, such as differences in the operating conditions of color television imaging devices and changes in ambient light over time.
(9) in the figure, (As shown in IIK, it is very possible that the video signals of each channel will be so misaligned that there will be no overlapping parts. Also, unless the subject to be imaged has a very special color tone, (e.g. red, green.

In the case of a subject consisting of a single color of blue), figure αυ,
It is highly unlikely that the video signal of any channel will be deleted like a'a, so in practice there is almost no possibility of indistinguishability or misjudgment in any case.

Now, we have explained the registration adjustment in the horizontal direction along the scanning direction of the image plane.
An AM or the like is provided, and the Eirin signal stored in this memory is sequentially read out in the vertical direction of the image surface at a desired part of the image surface, and the read Eirin signal is subjected to the same processing as the horizontal registration adjustment described above. If you do this, you can automatically adjust the registration in the vertical direction, so you can automatically adjust the registration in both the horizontal and vertical directions.
According to this embodiment, accurate registration can be automatically obtained whenever necessary, and a color television signal of excellent image quality can be easily obtained.

As explained above, according to the present invention, it is possible to easily adjust the registration as needed while damaging a general subject without using a damaging optical system with a built-in special test pattern. Because it can be performed automatically, it eliminates the drawbacks of conventional technology and allows for accurate registration at all times, even in damaged equipment that has various operating conditions and is prone to misregistration, such as not only studio type cameras but also portable type television cameras. It is possible to provide a compact and low-cost auto-registration device that can maintain the image quality and obtain a color television signal with excellent image quality.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of a registration adjustment method in a conventional color television camera, FIG. 2 is a block diagram showing a conventional example of an auto-registration method, and FIG. 3 is a diagram showing an example of an auto-registration method according to the present invention. Block diagrams showing one embodiment, FIGS. 4, 5, and 6
Each figure is a timing chart for explaining the operation. 1 to 3...Damage system, 14...Control circuit, 15゜16...Registration WA formal wear, 18...Comparator (window comparator or external -Sive-OR circuit), 19, 20...
...Edge signal generation circuit. "nH'□- Agent Patent Attorney Kenji Takeshi (1 person) - Figure 1 Figure 2 / 4 1j Figure 3 Figure 4 Z - Old U-1" - 7-" 辷-m- "L- 11" Ku--1-111 North Jul-"-11-1111-11"-111 Figure 51 Z -Fm"C-Y-"C--1-- -" - 111111 Luu - 11111 - You - " - 111 Figure 6 Z - Old [ "" - Z - -lL - ■ - - ■ - m - - 11 --”1-11

Claims (1)

[Claims] A predetermined level difference between two systems of video signals to be adjusted for image registration in a television camera that is equipped with multiple image sensors and obtains a color television signal by combining video signals from multiple systems. A level difference signal representing the above-mentioned two systems and first and second edge signals are generated from each of these two systems of video signals, and by arithmetic processing of these level difference signals and the first and second edge signals, the video system of the two systems is calculated. An auto-registration method for a color television camera characterized by obtaining a discrimination signal indicating the direction of registration deviation between signals.