JPH0270176A - Phase adjuster for TV signal generation equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a method for adjusting the synchronization signal of each input signal and the phase of a color burst signal when mixing, editing, or switching a plurality of television signals. This relates to a phase adjustment device that adjusts the phase.

[Prior Art] In color television, a vertical synchronization signal (hereinafter r
It is abbreviated as VJ. ) determines the scanning start point of each frame and field, and the horizontal synchronization signal (hereinafter referred to as "rH")
It is abbreviated as ) to determine the scanning start point of each scanning line,
The screen is colored by detecting a burst signal and restoring the color subcarrier (hereinafter abbreviated as rSCJ).
The color phase of each pixel is determined by a color signal based on this SC. According to the Radio Law, there are no regulations regarding the phase of SC and H (hereinafter referred to as rsc/11 phase), and the relative position between H and video signal is only determined at its minimum value. There is.

The use of multiple television signals, for example multiple television cameras, and the mixing, editing, or switching of these camera outputs is hereinafter collectively referred to as "switching." ), the difference in screen position and color tone due to the difference in the H phase and SC phase mentioned above becomes noticeable, so it is necessary that the SC phase and H phase of each input signal are within the tolerance range at the switching point. becomes.

The first method for phase alignment is to use a device with a synchronization coupling (hereinafter referred to as rGLJ: genlock) function for each camera, and use a reference synchronization signal generator (hereinafter referred to as synchronization signal generator) on the switch side. is abbreviated as rSGJ.)
The method used was to send a DBS signal (black burst signal) containing a composite synchronization signal and a burst signal from the computer and synchronize with this signal. However, even if you do this, various conditions such as delay time differ depending on each TV camera, and in addition, the phase will be different at the above switching point due to the difference in the length of the connection cable, so adjust the cable length. Or, on each camera side, the H phase shifter in the SG circuit was adjusted to match the H phase, and the SC phase shifter was separately adjusted to match the SC phase.

Since this method is time-consuming and lacks stability, a second method is to separate SC and H for each input signal at the switching point, and compare the SC and H of the reference SG. A method has been proposed in which the difference is corrected by a delay circuit, mixed and fed back to each television camera, thereby automatically keeping the SC phase and H phase within a tolerance range (for example, Japanese Patent Publication No. 60-13636 reference). moreover,
In recent years, as teletext has been implemented and digital television equipment has become a trend, it has become necessary to determine the synchronization signal waveform in detail.
onicIndustries As5ociatio
n: Electronic Machinery Industries Association), the 4-field sequence in which the sync signal and burst signal go around in 4 fields, the details of the composite sync signal waveform, the clarification of the SC phase and H phase, the time scale, and the width of the horizontal sync signal. Instead of R, which is easy to measure,
The RS-170A standard, whose main contents are expressed in S, was announced. This standard also includes standards not found in the Radio Law, in particular the provision that the SC phase is O ± 10° (31 ns) at the midpoint of the leading edge of H.
It is called ``SC/11 phase'' or ``SC/11 timing'', and is important in digitizing studio equipment, VTIt, television editing machines, etc. SG based on human broadcast signal
An element that corrects the signal to comply with the FLS-170A standard has already been developed, for example Sony's L
As an SI, there is CX Near 930A.

Next, as a third method, for multiple television signal generators (for example, multiple television cameras), an SG using an element that satisfies the above R5-170A standard (a crystal piece is connected to the element, and an SC and ) and GL
The device is built in, and when switching TV signals, the automatic video delay line (AVDL) is used to adjust the phase difference caused by the difference in cable length between each TV camera in the front stage of the switch, and the signal conforms to the R5-170A standard. A method has been proposed to obtain the .

[Problems to be Solved by the Invention] As stated in the previous section, in order to respond to future developments in television technology, including digital television, future television 41 PJs must comply with the Its-170A standard or this standard. It is desirable to meet alternative standards.

The second method described above involves switching between multiple TV inputs.
This is an improvement on the first method, as the SC phase and H phase are adjusted to the reference SG independently, and the circuit that adjusts the phase between SC and H to the R5-170A standard is Not provided. Of course, standard S
Use a G that meets the R5-170A standard and accurately measure the S.
If the phases of C and H are adjusted to this, the output will be Its-
Although it satisfies the 170A standard, since SC and H are adjusted separately, the phase of SC must be within ±1° of the phase of SC of the reference SG, and the phase relationship must be correct.
It is difficult to match the SC/++ phase of the R5-170Δ standard (within O±40° at the midpoint of the leading edge of H). At this time, on the TV signal generating equipment side, the above-mentioned R5-170
If you use SG and GL equipment that satisfies the R5-170A standard, you can obtain a signal that satisfies the R5-170A standard at the connection point, but television signal generation equipment does not necessarily meet the R5-170A standard.
Since the TV is not equipped with an SG and GL device that satisfies the 170A standard, in this case it is necessary to modify the television signal generating equipment and add and install the above-mentioned SG and GL device.

In the third method of using SG and GL devices with a synchronization signal generation function that conforms to the R5-170A standard on the TV signal generation equipment side, the TV signal generation equipment without this equipment will need to be modified. , AVDL on the video signal signal line
There is a drawback that the insertion of this material deteriorates its characteristics. That is, although it is desirable that the amount of phase shift of AVDL does not change depending on the frequency, it is difficult to completely eliminate this change, so it is inevitable that the amount of phase shift will change due to the frequency difference between SC and H. In addition, since the AVDL circuit cascades constant gain phase shift circuits in multiple stages (usually eight or more stages), video signal characteristics (DG-differential gain, DP-differential phase, frequency characteristics) deteriorate. Because of these drawbacks, SC's 3.
It is only possible to correct ±40° around 58 MIIz, and the difference in cable length from each signal generator (several microns) is sufficient.
s) cannot be corrected.

In view of the above points, a first object of the present invention is to provide output cutting equipment for a plurality of television signal generating devices, in which the television signal generating devices meet a specific standard, for example, R5-170A.
It is not necessarily necessary to have a built-in SG that complies with the JJu rating, but it is possible to target a device that has at least an SG with a normal GL function or a pulse regenerator, and each TV signal generating device and phase adjustment device can be used. The cable lengths to be connected can be different up to about 1000 meters, and the standard SG does not require that it conform to a specific standard.Moreover, the length of each TV signal generating device is automatically changed at the switching point. An object of the present invention is to provide a phase adjustment device that can align the SC/)1 phase.

A second object of the present invention is to convert the television signals generated by each television signal generating device to a specific standard, for example, R5-170^.
The object of the present invention is to provide a phase adjusting device that can be adapted to standards.

Furthermore, a third object of the present invention is to provide a harmonizing device that is simple in construction, easy to adjust, and has a high degree of stability.

[Means for Solving the Problems] In order to achieve such an object, the present invention provides a means for switching a plurality of television signals from a plurality of television signal generating devices, and a means for switching each of the plurality of television signal generating devices. It has a plurality of phase modulators provided corresponding to the phase modifiers, and a reference synchronization signal generation means provided in common to all of the multiple phase modifiers, and from the phase modifier, a plurality of Control so that the phase of the synchronization signal and the phase of the color subcarrier of the television signal at the switching point of the television signal match the phase of the reference synchronization signal and the phase of the reference color subcarrier from the reference synchronization signal generation means, respectively, with predetermined accuracy. The black burst signal is fed back to the corresponding one of the plurality of TV signal generators, and the TV signal generator outputs the phase of the reference synchronization signal and the Q-reference sub signal. In a system that switchably outputs a synchronization signal matching the phase of a carrier and a playback signal having color subcarriers, means for separating the synchronization signal and color subcarrier of a television signal that is switched and inputted. a means for separating a horizontal synchronization signal and a vertical synchronization signal from the separated synchronization signal;
a first comparison means for comparing the phase of the horizontal synchronization signal that has been jijied with the phase of the horizontal synchronization signal in the reference synchronization signal; a first phase shifting means for matching the phase of the horizontal synchronization signal with a predetermined accuracy; a second comparing means for comparing the phase of the separated color subcarrier with the phase of the reference color subcarrier; and a comparison output from the comparing means. a second phase shifter for matching the phase of the color subcarrier separated by the reference subcarrier with a predetermined accuracy; the separated vertical synchronization signal, the horizontal synchronization signal from the first phase shifter and the second phase shifter; The present invention is characterized by comprising means for receiving a color subcarrier from a phase means, generating a black burst signal of a predetermined standard, and supplying the black burst signal to a corresponding television signal generating device.

Here, the first phase shifting means may include a third phase shifting means for coarsely adjusting the phase of the separated horizontal synchronizing signal.

The second comparing means may include fourth phase shifting means for coarsely adjusting the phase of the separated color subcarriers.

[Function] In the present invention, with the above configuration, the television signals from each television signal generation device at the switching point are completely converted to a special standard, for example, R5-170A, without any adjustment operation in the phase adjustment device. A television signal that conforms to the standard and has an SC phase that matches the standard SG within a predetermined accuracy, for example within a range of ±1°, can be obtained.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the apparatus of the present invention.

In FIG. 1, reference numeral 1 denotes a television signal generating device, such as a television camera or VTR, which generates a VBS signal (composite video signal: No. 48, which is a video signal plus a DBS signal). Note that the number following the hyphen in all the symbols indicates the order of the n television signal generators. Reference numeral 2 denotes a synchronization unit No. 3 complete generator or pulse reproducing device built into the television signal generator 1, and a device used alone, such as a television camera, is composed of an SG and a GL device. This SG may meet a special standard, such as the R5-1708 standard. Alternatively, as in the present invention, when receiving an external synchronization signal from another SG, the pulse regenerator may be a GL device only.

Reference numeral 3 denotes a switching device having a phase adjustment function, and the input VBS from the television signal generator 1 is inputted to the phase adjustment device 5 through a buffer amplifier 4 and a switching point 6. The BBS signal is returned from the phase modifier 55 to the TV signal generator fEW I, and as a result, the TV signal generator 1 is output from the R5- It operates to generate a VBS signal that conforms to the 1708 standard and whose timing matches the standard SG7 possessed by that station.

VBS from each television signal generator 1 at switching point 6
The signal is branched and input to a switch 8, and a cross point 9 performs switching according to the video to be output. When mixing or editing, the output from the switch 8 is supplied to the mixer or editor 11 through the buffer amplifier 110-1=10- for mixing or editing, and the video output is sent from the terminal 12. Take it out.

Next, details of the phase adjustment circuit 5 will be explained. 37 is R5
- LSI for generating synchronization signals compatible with 1708
22 is a synchronous signal generator 3
This is a GL IC that drives the SC phase comparator 23, the V-H separator 24, and the H phase comparator 25.
has.

The VBS signal from the cut-off point 1 moxibustion point 6 is separated into an external synchronization signal and an external SC by the synchronization separation circuit 21, and the G1. IC2 for
2 of V·ll+J[ is supplied to the device 24 and the SC phase comparator 23, respectively. On the other hand, from the reference SG7, the base 41 synchronization signal and the base aSC are sent to the H phase comparator 2.
5 and SC phase comparator 23, respectively.

The phase difference between the external SC and the reference SC is compared by the SC phase comparator 23 built into the GL IC 22, and the comparison output is supplied to the SC variable phase shifter 28 and the SC phase indicator 35 via the amplifier 33. When the phase difference between these two SCs falls within a predetermined range, the lamp of the SC phase indicator 35 is turned on.

The above external synchronization signal is separated into ■ and H by the V/II separator 24 and outputted respectively, and H is output from the GL IC.
It is also supplied to the H phase comparator 25 built in 22 to compare the phases of both H, and the comparison output is passed through the amplifier 34 to the H phase comparator 25.
A variable phase shifter 32 and an H phase indicator 36 are supplied. When the phase difference between both H's falls within a predetermined range, the lamp of the H phase indicator 36 is turned on.

The synchronization signal generator 37 has 4f, c(
fsc is the frequency of SC) is supplied via an SC phase shifter 26 and an SC variable phase shifter 28. In this synchronization signal generator 37, this '1fsc is used as a clock, and is aLM'd to 1/4 and outputted as SC. In addition, synchronization signals H and (2), blanking signal BL, and burst flag BF are also created and output.

The various signal generating circuits in this synchronizing signal generator 37 are reset by the H and (2) inputs, thereby correcting the phases of the various output signals for each H.

Therefore, in this embodiment, this synchronization signal generator 37 includes:
■ and 14 formed by the GL IC 22 are supplied to the synchronizing signal generator 37 directly and through the H phase shifter 30 and the H variable phase shifter 32, respectively, and the timing of ■ and the phase-shifted H is In other words, these various signal generation circuits are reset at the phase adjusted timing.

A 4fsc signal is applied to the SC phase shifter 26,
The SC phase is coarsely adjusted by switching the switch 27, and the location where the SC phase indicator 35 lights is selected.

Note that this rough adjustment of the SC phase can also be automatically performed by combining an up-down counter with the SC phase shifter 26 instead of the switch 27.

As mentioned above, the SC variable phase shifter 28
4fs due to the phase difference between C and SC from reference SG7.

By controlling the phase of the reference SG7, the phase of the output signal can be adjusted within a range of approximately ±1°, and as a result, the inactive period between the above H reset pulses can be adjusted to within a range of about ±1°. Also functions to maintain the SC/)1 phase of the output signal from the synchronization signal generator 37.

The H phase shifter 30 is a shift register that roughly adjusts the H phase, and the 178 step down converter 29 converts 4fS to 1/2.
The fsc signal and H are added, and the switch 31
By switching, the H phase can be changed in 8 steps by 280 x 2 ns for one cycle of 172 fsc, and the part where the H phase indicator 36 lights is selected.

Incidentally, the rough adjustment of this day's phase can also be automatically performed by replacing the switch 31 with an up/down counter in combination with the H phase shifter 30.

As described above, the H variable phase shifter 32 is a phase shifter controlled by the output of the H phase comparator 25, and is a known monostable multivibrator (voltage control type).
can be used. The output signal from this variable phase shifter 32 is used as an H reset pulse that determines the H phase of the synchronizing signal generator 37.
The purpose of use is not only to match the H phase of the synchronization signal generator 37, but also to perform correction when the SC/+1 phase relationship is not maintained.

The synchronization signal generator 37 outputs four signals: H and ■ synchronization signals, a blanking signal BL, a burst flag BF, and a subcarrier SC, and these four signals are added to a mixer 38 to create a BBS signal. This S signal is distributed to the television signal generator 1 through the output amplifier 39 to operate the synchronizing signal generator 2.

The BBS signal created in this way is correctly R5-
It conforms to the 1708 standard, and its phase is within a range of ±1° with respect to the SC of the standard SG7.

In this way, in this embodiment, a Bns signal that is in phase with the reference SG with high precision and complies with the R5-170A standard can be created by the phase modulator M5. The GL-equipped synchronizing signal generator or pulse signal reproducing device 2 built into the device only needs to have 61 simple functions. Of course, a complete 61
It goes without saying that the SG may also be a functional SG.

In this way, the ν8S signal from each television signal generator 1-1 to 1-n at the switching point 6 satisfies the R5-170A standard, and its SC phase matches within a range of ±1° with respect to the reference SG. do.

[Effects of the Invention] As explained above, according to the present invention, the switched television signal generator is a simple S
Any television signal generator can be the subject of the switch, as it may be equipped with a G or pulse regenerator and does not necessarily require the possession of a fully functional SG.

The base $SG does not need to conform to any particular standard; any SG can be used.

In the phase adjuster, the SC and H phases are coarsely adjusted manually or automatically, so the difference in cable length is 100%.
The output phase between each TV signal generator up to about 0m can be automatically aligned at the switching point, and special standards such as the R5-17OA standard can be created using a dedicated LS.
I), it is possible to create a BBS signal that reliably satisfies the required standards without making any special adjustments. Phase alignment with reference SG is automatically ±1°
This can be done with an accuracy of

Moreover, the LSI described above as a synchronization signal generator that creates signals of the R5-1708 standard is compatible with other standards, such as PA
Since it is also possible to generate signals that comply with the L and SECΔM standards, it is immediately possible to generate signals to PAL or SEC8M. Furthermore, by replacing this LSI with an LSI or circuit of another standard, it is possible to generate a television signal of any desired standard.

Furthermore, since the present invention does not use A V OL,
Since it does not affect the output VBS signal, the image quality does not deteriorate.

As described above, according to the present invention, the television signal generator only needs to have an SG with a simple GL device or a pulse regenerator, and it is possible to use the R5-170 on the hour wheel and reliably.
Since it is possible to align the phases of television signals between a plurality of television signal generators that satisfy a desired standard such as the eight standards, the benefits are truly significant.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of a device according to the invention. DESCRIPTION OF SYMBOLS 1... Television signal generator, 2... Pulse regenerator or synchronization signal generator, 3...
...Switching device with phase adjustment function, 4...+1 A. 5... Phase adjuster, 6... Switching point, 7... Base S6. 8...Switcher, 9...Cross point, lO...BA. 11... Mixer/editor, 12... Output terminal, 21... Synchronous separator, 22... GL IC. 23...SC phase comparator, 24...V-H separator, 25...H phase comparator, 26...SC phase shifter, 27...Switcher, 28...SC variable phase shift 29...L/8 stepdown device, 30...H phase shifter, 31...Switcher, 32...H variable phase shifter, 33, 34...Amplifier, 35...・SC phase indicator, 36...H phase indicator, 37...n5-170A synchronization signal generator LSI, 3
8... Mixer, 39... Output amplifier.

Claims (1)

[Claims] 1) means for switching a plurality of television signals from a plurality of television signal generating devices; and a plurality of phase adjusters provided corresponding to each of the plurality of television signal generating devices; , a reference synchronization signal generating means provided in common to all of the plurality of phase adjustment devices, and the phase adjustment device generates a synchronization signal of the television signal at a switching point of the plurality of television signals. generates a black burst signal that can be controlled so that the phase of the reference synchronization signal and the phase of the color subcarrier match with the phase of the reference synchronization signal and the phase of the reference color subcarrier from the reference synchronization signal generation means, respectively, with a predetermined accuracy; The burst signal is fed back to a corresponding one of the plurality of television signal generating devices, and the television signal generating device generates a synchronizing signal matching the phase of the reference synchronizing signal and the phase of the reference subcarrier. A system for outputting a television signal having color subcarriers in a switchable manner, comprising means for separating a synchronization signal and a color subcarrier of a television signal that is switched and input, and a means for separating a horizontal synchronization signal and a vertical synchronization signal from the separated synchronization signal. means for separating the horizontal synchronization signal from the horizontal synchronization signal; first comparison means for comparing the phase of the separated horizontal synchronization signal with the phase of the horizontal synchronization signal in the reference synchronization signal; a first phase shifting means for matching the phase of the horizontal synchronization signal in the reference synchronization signal with the phase of the horizontal synchronization signal in the reference synchronization signal with a predetermined accuracy; a second comparison means for comparing the separated color subcarriers with a predetermined accuracy, and a second phase shift means for matching the phase of the separated color subcarrier with the phase of the reference subcarrier with a predetermined accuracy based on the comparison output from the comparison means; A black burst signal of a predetermined standard is generated in response to the vertical synchronization signal from the first phase shifter, the horizontal synchronization signal from the first phase shifter, and the color subcarrier from the second phase shifter. A phase adjusting device for a television signal generating device, characterized in that it comprises means for supplying the signal to the corresponding television signal generating device. 2) The phase adjusting device for television signal generating equipment according to claim 1, wherein the first phase shifting means includes a third phase shifting means for coarsely adjusting the phase of the separated horizontal synchronizing signal. 3) The phase adjustment device for television signal generation equipment according to claim 1 or 2, wherein the second comparing means includes a fourth phase shifting means for coarsely adjusting the phase of the separated color subcarriers. .