JPS6243294A - Test signal generator - Google Patents

Abstract

PURPOSE:To generate a desired test signal easily and inexpensively by recording a digitally modulated test signal on an information signal recording medium and subjecting the test signal reproduced from the information signal recording medium to a prescribed signal processing. CONSTITUTION:A signal related to still pictures is subjected to a prescribed digital signal processing by, for example, the component encoding system of luminance and color difference signals and is recorded on a spiral track of a disc 12. A digital video signal or the like is written in or read from a memory circuit 15 under the control of the output of a read/write controller 16. Luminance picture element data and two kinds of color difference picture element data read out from the memory circuit 15 are supplied to a D/A converting circuit 17 and are converted to a luminance signal Y and color difference signals R-Y and B-Y, and they are supplied to an encoder 18.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a test signal generating device that generates a test signal that is used as a reference when adjusting or repairing video equipment such as a television receiver or display device.

(Prior Art) Conventionally, when adjusting or repairing video equipment such as television receivers and display devices, tests that generate test signals, such as color par signals and multi-burst signals, are used as standards for adjustment. A signal generator was used.

(Problem to be solved) However, many conventional test signal generators are configured to generate only a single test signal, so it is necessary to have as many test signal generators as there are required test signals. There are also test signal generators configured to generate a plurality of test signals, but such test signal generators have the problem of being very expensive.

Furthermore, since normal test signals are different from image signals that exist in the natural world, it is essential to adjust and test color balance using test signals of natural images. The test signal generator that generates the test signal has a very complicated configuration and is very expensive, so the original image is usually photographed with a video camera and this output signal is used as the test signal. It is difficult to make conditions uniform, there are problems with color reproducibility, and there are problems in that good test signals cannot be obtained at low cost.

Therefore, the present invention records a digitally modulated test signal on an information signal recording medium (hereinafter also referred to as a disk), and performs predetermined signal processing on the test signal reproduced from the information signal recording medium to obtain a desired test signal. The purpose of the present invention is to provide a test signal generator that generates test signals easily and inexpensively.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a test signal generating device having a configuration as shown in FIG. The test signal generating device shown in FIG. 1 includes: an information signal recording medium (disk) 12 on which information signals in the form of digital signals related to test signals of natural images are recorded; a control circuit (keyboard 21, control circuit 22) that outputs a control signal; a reproduction device 23 that reproduces a test signal in the form of a digital signal corresponding to the control a signal from the information signal recording medium 12; and an output of the reproduction device. The digital signal processing circuit 24 performs predetermined digital signal processing on the signal in accordance with the control signal 311 and outputs a test signal in the form of a video signal.

(Example) By the way, a disc in which a video signal and a reputation signal are each digitally modulated and then synthesized in time series and recorded on a concentric or spiral track, for example, as a change in geometric shape. and disc playback devices are known.

In particular, a digital signal can be completely restored to the original digital signal if the S/N ratio level of the reproduced signal exceeds a certain value, so for the purpose of high-quality recording and reproduction, the analog video signal is digitally pulse modulated onto the disc. A digital video signal that has been modified (for example, pulse code modulation) can be recorded and played back.

As already proposed by the present applicant, the above-mentioned disk has the function of detecting the change in capacitance formed between the electrode of the sensor and the disk and reproducing the recorded green signal. have different frequency tracking t, I
There are disks and disk playback devices in which a reference signal for I use is recorded, and the level of this reference signal is compared during playback, and tracking control is performed in response to the comparison result, thereby eliminating the need for a sensor guide groove. .

FIG. 2 is a block system diagram of an example of a disk recording system which is a component of the test signal generating device according to the present invention.

In Fig. 2, input terminals 1, 2 and 3 are used to receive various necessary natural images (still images), for example, captured by a 525-line color television camera. Primary color signals of red (R), green (G), and blue (B) are input and supplied to the 7-trix circuit 4.

The matrix circuit 4 generates a luminance signal (Y), a color difference signal @(RY> and (B-Y)) from these three primary color signals, and converts these signals into an analog/digital signal (hereinafter referred to as A).
(sometimes referred to as D) is supplied to the conversion circuit 5.

The AD conversion circuit 5 samples these input analog signals at a sampling frequency of, for example, 9 [MHz], and then converts them into m children, so that, for example, the number of hangings per pixel (sampling point) is 8 p1-1.
digital signals (pixel data) are generated and these pixel data are provided to the memory 6 #8.

The memory 6 receives a digital luminance signal and two types of digital color difference signals in response to write pulses from the read/write controller 7.

Thereafter, under the control of the read/write controller 7, the memory 6 stores one of the pixel data constituting one screen obtained by digital pulse modulating the analog video signal.
Read out pixel data for one field serially.

On the other hand, each pixel data of two types of color difference signals (R-Y) and (B-Y) is also read out from the memory 6.

Here, the memory 6 stores, for example, four luminance pixel data and two types of color difference signals (R-Y) and (B-Y) pixel data. The digital video signal of the signal 74-mat transmitted in time series for each medium is read out.

The digital video signal read out from the screen 6 is supplied to the signal processing circuit 8 shown in FIG.
After being synthesized in time series with, for example, a digital audio signal or a control signal for random access,
The signal is supplied to the modulation circuit 10.

The modulation circuit 10 modulates the input digital signal using a predetermined modulation method suitable for recording and reproduction, and supplies the modulated wave obtained thereby to the recording device 11.

The recording device 11 is, for example, the above? & A modulated laser beam obtained by modulating a laser beam with a modulated wave intermittently exposes the photosensitizer on the recording master, and then this recording [51
This is an apparatus for creating a disk 12 through a well-known developing process and a machine making process.

The spiral track of this disk 12 contains the digital video signals described above, that is, various necessary test signals,
In other words, a signal related to a still image is recorded as a signal that has been subjected to predetermined digital signal processing using, for example, a component encoding method for luminance signals and color difference signals.

The present invention is an apparatus for reproducing digital video signals from a recording medium such as the disk 12 described above, and FIG. 1 is a block diagram of an embodiment of the test signal generating apparatus according to the present invention.

In FIG. 1, the green signal recorded on the disk 12 is reproduced by a pickup circuit 13 using a known capacitance change method, and then amplified to a predetermined level and sent to a demodulation circuit 13.
The signal is supplied to the demodulation circuit 14, where it is subjected to signal processing such as NRZ demodulation, error detection, and error correction, and demodulated, and then supplied to the memory circuit 15.

The memory circuit 15 includes a read/write controller 16
Under the control of the output of the digital video recorder No. 418, etc., is written and read.

Note that if the input digital signal of the memory circuit 15 also includes a digital audio signal, that is, the digital audio signal is supplied from the input terminal 9 shown in FIG. 2 and this digital audio signal is recorded on the disk 12. If it is, the reproduced digital audio signal will be included, but since this is not directly related to the present invention, only the operation of increasing and reading out the digital audio signal will be omitted. The digital video signal is read out separately from the digital video signal, and is supplied from the output terminal 25 to a demodulation circuit (not shown in FIG. 1), where signal processing for reproduction is performed and the original 8. will be restored.

The luminance pixel data and the two types of color difference pixel data read out from the memory circuit 15 are each supplied to a digital-to-analog (hereinafter also referred to as DA) conversion circuit 17.
Here, luminance signal Y, color difference signal (RY), (B-Y)
After that, it is supplied to the encoder 18.

The encoder 18 receives M quasi-synchronous signals such as a horizontal synchronous signal, a vertical II signal, and a color burst signal, which are generated by a signal generation circuit not shown in FIG. 17 output signals are supplied, and from these signals a color video signal conforming to a predetermined standard television system or a video signal such as a three primary color signal is generated and outputted to the output terminal 20.

In other words, the output terminal 20 outputs a natural image test signal (still image).

Further, 21 is a keyboard for inputting information to select a required test signal, and a selection signal corresponding to the selection information inputted to the keyboard 21 is supplied to a control circuit 22, and the control circuit 22 controls the selection signal corresponding to the selection signal. Play signal H position 2
3 and the digital signal processing circuit 24.

Although not shown in FIG. 1, the disc 12 and pickup circuit 13, a motor for rotating the disc 12, a sensor positioning control circuit, etc. are included in the playback device 2.
The elements constituting the digital signal processing circuit 24, the demodulation circuit 14, the memory 15, the read/write controller 516, the DA conversion circuit 17, and the encoder 18 are the elements constituting the digital signal processing circuit 24.

For example, when an input to select a color burst signal is made on the keyboard 21, a control signal for reproducing the color burst signal recorded on the disc 12 is supplied to the reproduction device 23. By this control signal, the reproducing device 'e2
3 searches for the address where the color burst signal is recorded on the disk 12, enters the playback state, and supplies the playback signal to the digital signal processing circuit 24. The digital signal processing circuit 24 receives the control signal supplied from the iII11m circuit 22. After writing the reproduced signal outputted from the reproduction 1iiff 23 to a predetermined address in the memory, the stored contents are read out at predetermined intervals, converted into a television signal format, and outputted from the output terminal 20.

In other words, when the test signal is output from the output terminal 20, the disc 12 is in the playback state until the digital signal processing circuit 2/ output from the playback device takes in the test signal, but -H,
After the reproduction signal output from the reproduction device 23 is taken into the digital signal processing circuit 24, the reproduction \A position 23 is set to i! II
Since it remains in a dormant state until a new request is generated from the control circuit 22, the lifespan of the disk 12 and the lifespan of the playback device are not a problem.

In addition, various test signals can be recorded on the disk 12 within the range allowed by the recording capacity of the disk 12, and by exchanging the disk 12, the number of test signals that can be generated can be further expanded and any number of test signals can be recorded. A test signal can be obtained.

Furthermore, by recording a natural image on the disk 12 as a test signal, the present invention has a simpler configuration and lower cost than conventional devices, and outputs an original image from a conventional color video camera. It is possible to obtain a test signal of a natural image that is more stable than the test signal.

Furthermore, when the test signal output from the output terminal 20 deteriorates beyond a certain standard, the same test signal as the deteriorated test signal is recorded on another track of the disk 12, and the degree of deterioration of the reproduced signal is checked. It is also possible to configure the system so that it is detected and the playback location is automatically switched to another rack.

In other words, when the reproduction signal output from the reproduction device 23 has deteriorated below a certain standard, this is detected and the control circuit 22
In response to this detection signal, the i, 1110 circuit 22 reproduces the same type of test signal as that currently output from the digital signal processing circuit 24 from the disk 12 using the reproduction device 23. 11 is supplied to the playback device 23 and the digital signal processing circuit 24.

Furthermore, once the digital signal processing circuit 24
After capturing the output signal of
As a stand, a digital signal processing circuit 24, a keyboard 21,
It is also possible to provide a plurality of υ11!1 circuits 22 and access the reproduction device 23 or supply the reproduction signal from the reproduction device 23 in a time-division manner or line-sequentially.

Further, as information related to the test signal output from the output terminal 20, for example, related information regarding the test signal is supplied as a digital audio signal from the input terminal 9 shown in FIG. Keep it
The output terminal 25 shown in FIG.
The playback digital audio signal output from mWll
, the audio signal may be an audio signal relating to a program of the computer, in which case the computer may be provided with the fame number 13 relating to the program. hand,
By operating the computer in accordance with this program, it is also possible to configure the computer to display information related to the test signal or provide voice guidance.

(Effects of the Invention) Since the present invention has the above-described configuration, it is possible to easily generate a necessary test signal, and in particular, it is possible to generate stable natural images with a relatively simple configuration and at low cost. This has the advantage that a test signal can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of a test signal generator according to the present invention, and FIG. 2 is a block diagram of an example of a disk recording system that is a component of the test signal generator according to the present invention. . 1.2.3...Input terminal, 4...Matrix circuit 5...Analog-digital (AD) conversion circuit, 6.15
...Memory circuit, 7.16...Read/Write controller, 8...
・Signal processing circuit, 9, 19...input terminal, 10...
Modulation circuit, 11... Recording device, 12... Information signal recording medium (disc), 13... Pick-up circuit, 1
4... Demodulation circuit, 17... Digital analog (DA
) Conversion circuit, 18... Encoder, 20.25...
Output terminal, 21... Keyboard, 22... 4 control circuit, 23... Playback device, 24... Digital signal processing circuit. Patent Applicant: Japan Victor Co., Ltd. Representative: Humanity
Some people are 1 year old

Claims (1)

[Scope of Claims] An information signal recording medium on which an information signal in the form of a digital signal related to a test signal of a natural image is recorded, a control circuit that outputs a control signal corresponding to a selection input of a desired test signal, and the information. a playback device that plays back a test signal in the form of a digital signal corresponding to the control signal from a signal recording medium; and a playback device that performs predetermined digital signal processing on the output signal of the playback device in accordance with the control signal to produce a test signal in the form of a video signal. A test signal generation device consisting of a digital signal processing circuit that outputs a test signal.