JPH0442681A - Characteristic correction device - Google Patents

Abstract

PURPOSE:To attain accurate level correction even in a signal recorder not having a time base collector by using a recovered reference pulse having a pulse width and a pulse level data being a quantized data so as to correct the level of a reproduced video signal. CONSTITUTION:The above device is provided with a reference pulse generating means 4 generating plural kinds of pulses with different level equivalent from a black level to a white level of a video signal, a pulse level data generating means 5 generating a data identifying the level of the output pulse, and reference data insert means 6, 7 inserting the reference pulse and the pulse level data into a recording video signal within a blanking period. Moreover, the device is provided with a level correction means 14 using the reference pulse and the pulse level data obtained from a reproduced video signal to correct the level of the reproduced video signal and with a signal interpolation means 10 replacing a fraction of a valid scanning number for a period into a signal pattern not causing a fraction in the case of channel division. Thus, even for a signal recorder not having a time base collector, the level is correctly corrected.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention automatically corrects distortion caused by nonlinearity of a signal processing system during recording and playback in a signal recording device, and corrects the playback signal level. The present invention relates to a characteristic correction device for performing correction.

[Conventional technology]

In signal recording devices such as VTRs, channel division recording is a method for recording wideband signals by dividing one signal into multiple channels to reduce the bandwidth required for each channel. There is a method.

In such a method, if the signal to be recorded is a television signal, the signal is divided into multiple horizontal scanning periods, distributed to multiple channels, and the distributed signals are time-extended and recorded. is used.

FIG. 19 shows an example of this method, in which the input video signal is distributed to two channels (A, B). FIG. 4(a) shows input signals, and numbers are given in chronological order as Hl, H2, H3, . . . for each horizontal scanning period. The input signal is divided into channel A and channel B for each horizontal scanning line, and is subjected to time axis expansion and converted into the recording signal format shown in FIG. 19(a).

When the time axis of the signal is expanded by channel division in this way, the bandwidth decreases for each channel, but 1
Since one signal will be recorded and played back in two systems,
If there is a difference in characteristics between the channels, this leads to deterioration of the reproduced image quality, such as scanning lines becoming conspicuous in the above example. Therefore, a device that automatically corrects the characteristic difference between channels is required.

V that performs channel division and records and plays back as described above.
An example of the structure of a characteristic correction device used in a TR is given in the document ``Kiyoshi Sasaki et al.: Band compression type high-definition VTR,''
National Technical Report Vol, 32 No.
, 4 J. FIG. 21 is a block diagram showing the configuration of this device. In the figure, 20 is a memory for storing the reproduced ramp signal, 21 is an averaging and checking circuit for averaging and checking the reproduced ramp signal, and 2
2 is a level correction table memory, 23 is a reference lamp signal data memory, 24 is a data processing circuit, 25 is a switch for switching the address of the level correction table memory 22, 26 is a reproduction signal input terminal, 27 is a reproduction lamp signal input terminal, 28 29 is a time axis data terminal, and 29 is a correction output terminal.

The conventional characteristic correction device is configured as described above, and records the ramp signal that changes from the black level to the white level within the vertical blanking period of the video signal, and reproduces this to adjust the recording level and playback level. I'm trying to take care of this. When the ramp waveform shown in FIG. 20(a) is recorded, if a distorted waveform as shown in FIG. By correcting the time axis and matching the timing with the ramp signal during recording, the input signal level and reproduction output level are made to correspond.

To explain this operation in detail, the reproduced lamp signal is first inputted to the averaging and checking circuit 21, where a plurality of reproduced lamp signals are added together to improve the S/N ratio, and the averaged reproduced lamp signal is Check the shape of the image and remove effects such as dropouts. The averaged and shape-checked reproduced lamp signal is stored in the reproduced lamp data memory 20 using the time axis data as an address.

Next, the data and address of the reproduction lamp data memory 20 are reversed and stored in the level correction table memory 22. The reference lamp signal data memory 23 stores the shape of the lamp signal at the time of recording, and if reproduced video signal data is given as the address of the level correction table memory 22 via the switch 25, the address of the reference lamp signal data memory 23 is stored. is determined, and level-corrected video signal data is obtained as the output of the reference lamp signal data memory 23.

[Problem to be solved by the invention]

Since the conventional characteristic correction device is configured as described above, the timing of the ramp signal during recording and the ramp signal during playback must be perfectly matched, so a very high precision time base collector device is required. In addition, if there is a time axis fluctuation within one horizontal period called velocity error, the timing cannot be completely matched between recording and playback in the second half of one horizontal period, and the recording level and There was a drawback that the correspondence with the playback level could not be set correctly.

In addition, if the video signal level is at the same level for a short period of time, such as the lamp signal used in conventional equipment, if the sampling position shifts, incorrect reproduced lamp data will be captured, making it impossible to perform correct level correction operations. There was a problem.

Furthermore, when performing characteristic correction using conventional equipment, depending on the standard of the recorded signal and the number of channels to be divided, when the signal is divided, a fractional horizontal period may occur near the end of the effective west side portion. .

For example, when a video signal with an odd number of effective scanning lines is divided into two channels, a fraction of a non-video portion occurs in one channel during one horizontal period in one frame.

The occurrence of this non-video portion causes unstable operation of the video signal clamp circuit, causing problems such as erroneous characteristic correction data being taken in (see FIG. 22).

This invention was made in order to solve the problems of the conventional devices as described above, and is a signal recording device that does not have a time base collector device. It is an object of the present invention to provide a characteristic correction device that can correctly perform a level correction operation even in a signal recording device in which a fraction of the number of lines occurs.

[Means to solve the problem]

The characteristic correction device according to the present invention includes a reference pulse generating means that generates a plurality of types of pulses having different heights corresponding to at least the black level to the white level of a video signal, and a pulse height data generation means for generating data for identification; reference data insertion means for inserting a pair of reference pulse and pulse height data into a blanking period of a recorded video signal; Level correction means for correcting the level of the reproduced video signal using the reference pulse and the pulse height data;
The present invention is provided with signal interpolation means for interpolating by replacing the period portion of a channel in which a fraction of the effective scanning line number occurs with a signal pattern of another channel in which a fraction does not occur during channel division.

Further, the characteristic correction device according to the present invention includes a reference pulse generating means for generating a plurality of types of pulses having different heights corresponding to at least the black level to the white level of a video signal, and an output pulse height of the reference pulse generating means. pulse height data generating means for generating data for identifying the pulse height; reference data inserting means for inserting a pair of reference pulse and pulse height data into the blanking period of the recorded video signal; Level correction means for correcting the level of a reproduced video signal using the obtained reference pulse and pulse height data; The signal interpolation means performs interpolation by replacing the scanning line portion with the signal pattern of one horizontal period one field before.

[Effect]

In this invention, the reference pulse has a time width, so even if the reproduced video signal includes time axis fluctuations, by sampling and holding the vicinity of the center of the reference pulse, the pulse height during reproduction can be determined. can. Further, since the pulse height data is quantized data, its value does not change even if it is subjected to distortion. Therefore, since it is possible to accurately match each of the multiple types of pulses of different heights corresponding to the black level to the white level inserted during recording during recording and during playback, it is possible to accurately match each of the pulses of different heights between the black level and the white level inserted during recording. Even if the signal recording device is not equipped with the following, level correction can be performed correctly.

Furthermore, even if a video signal to be recorded has a fractional part of a non-video signal due to channel division, the period is interpolated with the video signal of the channel that does not produce a fraction, so the signal actually recorded on the recording medium is There are no non-video parts.

Furthermore, in this invention, since the reference pulse has a time width, even if the reproduced video signal includes time axis fluctuations, by sampling and holding the vicinity of the center of the reference pulse, the pulse height during reproduction can be obtained. I can do it. In addition, since the pulse height data is quantized data, its value does not change even if it is distorted. Since each pulse can be accurately correlated between recording and reproduction, even a signal recording apparatus that does not have a time base collector device can correct the level correctly.

Furthermore, even if the video signal to be recorded produces a fractional portion of the non-video signal due to channel division, the period is
Since interpolation is performed using the video signal of one horizontal period before the field, there will be no non-video portion in the signal actually recorded on the recording medium.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a characteristic correction device according to a first embodiment of the present invention, in which a video signal with an odd number of effective scanning lines per frame is divided into two channels, and an 8-bit reproduction A An example will be explained in which a set of reference pulses of 256 different heights corresponding to the number of quantization levels of the /D converter and pulse height data in serial format are inserted into each channel during the vertical blanking period.

FIG. 1 shows a block diagram of a recording system according to a first embodiment of the present invention. In the figure, 1 is a channel division circuit that divides a recorded video signal into two channels, and 2 is a vertical and horizontal synchronization signal from the recorded video signal. Synchronous signal separation circuit that separates 3
is a gate pulse generation circuit that generates a gate pulse based on the synchronization signal separated in the synchronization signal separation circuit 2;
4 is a reference pulse generation circuit that generates reference pulses of 256 different heights from the black level to the white level according to the output of the gate pulse generation circuit 3; 5 is the reference pulse generation circuit 4;
A pulse height data generation circuit 67 generates data for identifying the height of an output pulse of A second reference data insertion circuit; 8, a signal switching circuit for interpolating the signal pattern of a channel in which no fractional portion occurs during the period of a fractional portion, which occurs during channel division; 9, a field discrimination circuit of the recorded video signal; The field discrimination circuit 10 is a signal interpolation control circuit that generates switching timing for the signal switching circuit 8 based on the synchronization signal separated by the synchronization signal separation circuit 2.

Further, FIG. 2 is a block diagram showing a reproduction system for one channel in the first embodiment of the present invention, and similar circuits are required for the number of divided channels.

In the figure, 11 is a reproduction A/D converter that A/D converts the reproduced video signal, 12 is a reference pulse selection circuit that selects the reference pulse data inserted at the time of recording from the output data of the reproduction A/D converter 11, and 13 is a A pulse height data selection circuit 14 selects pulse height data from the reproduced video signal, and 14 corrects the level of the reproduced video signal using the output data of the reference pulse selection circuit 12 and the output data of the pulse height data selection circuit 13. The level correction circuit 15 is a reproduction D/A conversion converter that converts the level-corrected video signal into D/A. Note that the synchronization signal separation circuit 2 and the gate pulse generation circuit 3 can be used for the recording system, but other circuits that operate in exactly the same way can also be used.

Next, the operation will be explained using FIGS. 1 to 7.

In FIG. 1, a channel division circuit 1 divides a recorded video signal into two channels. A synchronization signal separation circuit 2 separates vertical and horizontal synchronization signals from the recorded video signal. The gate pulse generation circuit 3 generates a vertical synchronizing signal portion (see FIG. 3(a)) of the channel-divided recorded video signal (see FIG. 3(a)).
Four horizontal periods before (see (b)), a gate pulse (see FIG. 3(e)) is generated that is high for one horizontal period.

The reference pulse generation circuit 4 first generates 256/256 pulses in the first half of the gate pulse (see FIG. 4(a)).
The pulse height data generation circuit 5 generates a serial number indicating the height of the reference pulse by reading out the reference pulse data of the height of the quantization level from the ROM (see FIG. 4 (c)). After that, the reference pulse data (255/256
．． 254/256. ..., 2/256.1/256)
The pulse height data corresponding to 1 is generated every vertical blanking period (see FIGS. 4(b) and 4(c)), and the pair of reference pulses and pulse height data are used as the first and second references. When the data is inserted into the recorded video signal of each channel by the data insertion means 6.7, an output signal as shown in FIG. 5 is obtained.

At this time, since the number of effective scanning lines per frame of the video signal to be recorded is an odd number and the number of channels to be divided is 2, one of the two channels is sent once per frame for one horizontal scanning period. A fractional part that is a non-video signal of length is generated, but since this fractional part appears at a fixed timing depending on the method of channel division (see Figure 6 (a) and (b)), it is separated by the synchronization signal separation circuit 2. The signal interpolation control circuit 10 generates a timing signal for signal interpolation using the vertical and horizontal synchronization signals and the discrimination output of the field discrimination circuit 9, that is, a switching control signal of the signal switching circuit 8 (see FIG. 6(C)). occur in advance. By the above operation, it is possible to obtain a recorded video signal output without fractional parts as shown in FIG. 6(a).

In FIG. 1, the switching control signal of the signal switching circuit 8 is low to select the output of the second reference data insertion circuit 7, and is low to select the output of the first reference data insertion circuit 6 for signal interpolation. The other side is considered high.

Next, in FIG. 2, the reproduced video signal, which is distorted during reproduction and has shrunk near the white level, is A/D-converted by the reproduction A/D converter 11. At the same time, the synchronization signal separation circuit 2 separates vertical and horizontal synchronization signals from the reproduced video signal, and the gate pulse generation circuit 3 generates a reproduction gate pulse that synchronizes the reproduced video signal including time axis fluctuations (7th
(See figure (a)). In accordance with this reproduction gate pulse, the reference pulse selection circuit 12 selects a reproduction reference pulse whose height has changed due to distortion (see FIG. 7(b)) from the output data of the reproduction A/D converter 11, and also selects a reproduction reference pulse whose height has changed due to distortion (see FIG. The data selection circuit 13 obtains pulse height data that allows identification of the pulse height at the time of recording from the reproduced video signal (see FIG. 7(C)).

Next, the level correction circuit 14 creates a level correction table by writing the corresponding pulse height data into the memory using, for example, the data of all reproduction reference pulses as addresses. A level correction operation such as reading a value from a level correction table using the output data as an address is performed, the reference pulse and pulse height data inserted during recording are removed, and then D/A conversion is performed by the reproduction D/A converter 15. A level-corrected reproduced video signal is obtained.

In the above embodiment, the reference pulse and pulse height data are inserted one set at a time in one horizontal period within the vertical blanking period, starting from the one with the highest pulse height. Insert one set from the lowest, or insert only the reference pulse in one horizontal period as shown in Figure 8, then insert only pulse height data in one horizontal period, or insert only the pulse height data in one horizontal period as shown in Figure 9. Any pattern may be used as long as a pair of reference pulse and pulse height data are inserted within the blanking period, such as inserting pulse height data first and reference pulse later. It has a similar effect.

In addition, in the above embodiment, the case where the number of effective scanning lines is an odd number and the number of divided channels is 2 has been described, but any combination that results in a fraction when the number of effective scanning lines is divided by the number of channels is similar to the above embodiment. The effect of this can be obtained. However, it goes without saying that in the recording system, reference data insertion circuits are required for the number of channels, and signal switching circuits and signal interpolation control circuits for signal interpolation are required for the number of channels on which signal interpolation is to be performed.

Furthermore, in the embodiment described above, level correction is performed in which the data of the reproduction reference pulse is used as an address and corresponding pulse height data is written in the memory, and during normal video periods, the output data of the reproduction A/D converter 11 is used as the address and a corrected value is read out. For example, the difference between reproduction reference pulse data and pulse height data is written into memory as correction data, and during a normal video period, the output data of the reproduction A/D converter is written as correction data as an address. If a discontinuous point occurs in the level correction data, create level correction data using a method such as reading out the data and adding it to the output of the reproduction A/D converter to correct the level, or by using software using a microcomputer. , other level correction methods may be used, such as interpolating the data.

Further, in the above embodiment, an example was explained in which binary pulse height data of high or low was used, but quantized data of three or more values may be used.

Furthermore, in the above embodiment, an example was explained in which the data of the reproduction reference pulse obtained during reproduction is used as is, but there is also a means for averaging and smoothing the data of a plurality of reproduction reference pulses, By combining measures such as not using reference pulse data, −
You can expect the effect of layers.

10 and 11 show a characteristic correction device according to a second embodiment of the present invention, in which a video signal with an odd number of effective scanning lines per frame is divided into two channels, and an 8-bit An example will be explained in which a set of reference pulses of 256 different heights corresponding to the number of quantization levels of the reproducing A/D converter and pulse height data in serial format are inserted into each channel during the vertical blanking period.

FIG. 10 shows a recording system block diagram of the second embodiment of the present invention. In the figure, 101 is a channel division circuit that divides a recorded video signal into two channels, and 102 is a channel division circuit that divides a recorded video signal into two channels. 103 is a gate pulse generation circuit that generates a gate pulse based on the sync signal separated in the sync signal separation circuit 102; 104 is a gate pulse generation circuit 103;
a reference pulse generation circuit that generates reference pulses of 256 different heights from the black level to the white level according to the output of the
105 is a pulse height data generation circuit that generates data for identifying the height of the output pulse of the reference pulse generation circuit 104; 106 and 107 are used to record a pair of reference pulses and pulse height data; first and second reference data insertion circuits for inserting into the blanking period; 10;
Reference numeral 8 denotes a memory circuit for storing a signal pattern for one scanning period for interpolating the fractional portions generated when the channels are divided, 109 a signal switching circuit for inserting an interpolation signal in the period of the fractional portions, and 110 a recording video. A field discrimination circuit 111 that discriminates the field of a signal is a signal interpolation control circuit that generates read/write timing for the memory circuit 108 and switching timing for the signal switching circuit 109 based on the synchronization signal separated by the synchronization signal separation circuit 102.

FIG. 11 is a block diagram showing a reproduction system for one channel in the second embodiment of the present invention, and similar circuits are required for the number of divided channels. In the figure, 112 is a reproduction A/D converter that A/D converts the reproduced video signal, 113 is a reference pulse selection circuit that selects the reference pulse data inserted during recording from the output data of the reproduction A/D converter 112, and 114 is a reference pulse selection circuit that selects data of the reference pulse inserted during recording. A pulse height data selection circuit 115 selects pulse height data from the reproduced video signal, and a pulse height data selection circuit 115 corrects the level of the reproduced video signal using the output data of the reference pulse selection circuit 113 and the output data of the pulse height data selection circuit 114. The level correction circuit 116 is a reproduction D/A converter that converts the level-corrected video signal into a D/A converter.

Note that the synchronizing signal separation circuit and the gate pulse generation circuit can be used for the recording system, but it is also possible to use different circuits that operate in exactly the same way.

Next, the operation will be explained using FIGS. 10 to 16.

In FIG. 10, a channel division circuit 101 divides the recorded video signal into two channels. Synchronous signal separation circuit 1
02 separates vertical and horizontal synchronization signals from the recorded video signal. The gate pulse generation circuit 103 generates a gate pulse (which is high in one horizontal period before four horizontal periods) of the channel-divided recorded video signal (see FIG. 12(a)) and the vertical synchronizing signal portion (see FIG. 12, etc.)). (see FIG. 12(C)).

The reference pulse generation circuit 104 generates a gate pulse (Fig. 13 (
In the first part of (see a)), first of all, 256/
The data of the reference pulse with a height of 256 quantization levels is
'This occurs due to methods such as reading from ROM (first
(See Figure 3 (b)). Then, the pulse height data generation circuit 105 generates serial format pulse height data indicating the height of the reference pulse (see FIG. 13(C)). onwards,
Reference pulse data that decreases by one quantization level (255/256, 254/256..., 2/
256.1/256) is generated every vertical blanking period (Fig. 13(b),
(See (C)). Then, the pair of reference pulses and pulse height data are sent to the first and second reference data insertion circuits 1.
When inserted into the recorded video signal of each channel at 06 and 107, an output signal as shown in FIG. 14 is obtained.

At this time, since the number of effective scanning lines per frame of the video signal to be recorded is an odd number and the number of channels to be divided is 2, one of the two channels is sent once per frame for one horizontal scanning period. A fractional portion of the length that is a non-video signal occurs, but this fractional portion appears at a timing determined by the method of channel division. As shown in FIG. 15(a), the signal at this time has a fractional part occurring once per frame before the characteristic difference correction signal. Using the vertical and horizontal synchronization signals separated by the synchronization signal separation circuit 2 and the discrimination output of the field discrimination circuit 110, the signal interpolation control circuit 111 outputs a timing signal for signal interpolation, that is, the signal A3 to the memory circuit 108. A read/write control signal for writing and reading in the next horizontal scanning line period (see FIG. 15(b)) and a signal switching circuit 1
By performing an operation of 0 or more in which the switching control signal 09 (see FIG. 15(C)) is generated in advance, a recorded video signal output without a fractional portion as shown in FIG. 15 is obtained.

In FIG. 15, the read/write control signal of the memory circuit 108 is high for reading and low for writing, and the switching control signal of the signal switching circuit 109 is low for selecting the output of the reference data insertion circuit 107 and low for selecting the output of the memory circuit 108. The one selected is considered high.

In FIG. 2, an A/D converter 1 reproduces a reproduced video signal that has been distorted during reproduction and has shrunk near the white level.
12 performs A/D conversion. At the same time, the synchronization signal separation circuit 102 separates the vertical and horizontal synchronization signals from the reproduced video signal, and the gate pulse generation circuit 103 generates a reproduction gate pulse that synchronizes the reproduced video signal including time axis fluctuations (Fig. 16). In accordance with this reproduction gate pulse, the reference pulse selection circuit 113 selects a reproduction reference pulse whose height has been changed due to distortion from the output data of the reproduction A/D converter 112 (see FIG. 16(b)). In addition, the pulse height data selection circuit 114 obtains pulse height data that can identify the pulse height at the time of recording from the reproduced video signal (first
(See Figure 6 (C)).

Next, in the level correction circuit 115, a level correction table is created by writing the corresponding pulse height data into the memory using, for example, the data of all reproduction reference pulses as addresses.
Performs level correction operations such as reading values from the level correction table using the output data of step 2 as an address, removes the reference pulse and pulse height data inserted during recording, and then performs D/A conversion at the reproduction D/A converter 116. Then, a level-corrected reproduced video signal is obtained.

In the above embodiment, the reference pulse and pulse height data are inserted one set at a time in one horizontal period within the vertical blanking period, starting from the one with the highest pulse height. Insert one set from the lowest, or insert only the reference pulse in one horizontal period as shown in Figure 17, and only the pulse height data in the next horizontal period, or insert only the pulse height data in the next horizontal period, or as shown in Figure 9. Any pattern may be used as long as a pair of reference pulse and pulse height data are inserted within the blanking period, such as inserting pulse height data first and reference pulse later, and the same pattern as in the above embodiment can be used. It has the effect of

In addition, in the above embodiment, the case where the number of effective scanning lines is an odd number and the number of divided channels is 2 has been described, but any combination that results in a fraction when the number of effective scanning lines is divided by the number of channels is similar to the above embodiment. The effect of this can be obtained. However, it goes without saying that in the recording system, reference data insertion circuits are required for the number of channels, and memory circuits for signal interpolation, signal switching circuits, and signal interpolation control circuits are required for the number of channels for which signal interpolation is to be performed.

Further, in the embodiment described above, level correction is performed in which the data of the reproduction reference pulse is used as an address and corresponding pulse height data is written into the memory, and during the normal video period, the output data of the reproduction A/D converter 112 is used as the address and a corrected value is read out. For example, the difference between reproduction reference pulse data and pulse height data is written into memory as correction data, and during a normal video period, the correction data is written using the output data of the reproduction A/D converter as an address. When level correction data is created by software using a method such as reading and adding it to the output of the playback A/D converter, or by using software using a microcomputer, if a discontinuous point occurs in the level correction data, the data Other level correction methods such as interpolation may also be used.

Further, in the above embodiment, an example was explained in which binary pulse height data of high or low was used, but quantized data of three or more values may be used.

Furthermore, in the above embodiment, an example was explained in which the data of the reproduction reference pulse obtained during reproduction is used as is, but there is also a means for averaging and smoothing the data of a plurality of reproduction reference pulses, By combining measures such as not using reference pulse data, -
You can expect the effect of layers.

[Effects of the Invention] As described above, according to the characteristic correction device according to the present invention,
A level correction table is created using a reproduction reference pulse with a pulse width and pulse height data which is quantized data, and the level of the reproduced video signal is corrected, so that the signal without a time base collector device can be used. Not only can the level correction operation be performed accurately in the recording device, but also interpolation can be performed by replacing the period portion of the channel in which a fractional part of the effective scanning line number occurs with the signal pattern of the channel in which the fractional part does not occur during channel division. This configuration has the effect of preventing erroneous detection of characteristic correction data due to unstable operation of the video signal clamp circuit during reproduction.

Further, according to the present invention, a level correction table is created using a reproduction reference pulse having a pulse width and pulse height data which is quantized data, and the level of the reproduced video signal is corrected. Not only can a level correction operation be performed accurately even in a signal recording device that does not have a base collector device, but also the signal of one horizontal period one field before the part of the channel where a fraction of the number of effective scanning lines occurs during channel division. Since interpolation is performed by replacing the pattern with a pattern, it is possible to prevent erroneous detection of characteristic correction data due to unstable operation of the video signal clamp circuit during reproduction.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a recording system of a characteristic correction device according to an embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of a reproduction system of a characteristic correction device according to an embodiment of the present invention, and FIG. 4, 5, 6, and 7 are explanatory diagrams of the operation of one embodiment of the present invention, and FIGS. 8 and 9 are explanatory diagrams of the operation of another embodiment of the present invention. FIG. 10 is a block diagram showing the configuration of a recording system of a characteristic correction device according to an embodiment of the present invention.
FIG. 1 is a block diagram showing the configuration of a reproduction system of a characteristic correction device according to an embodiment of the present invention, and FIGS. 12 and 13. FIGS. 14, 15, and 16 are explanatory diagrams of the operation of one embodiment of the present invention, FIGS. 17 and 18 are explanatory diagrams of the operation of another embodiment of the invention, and FIG. 19 is a signal recording device. 20 is a diagram for explaining the operation of the conventional example, FIG. 21 is a block diagram showing the configuration of the conventional characteristic correction device, and FIG. 22 is for explaining the operation of the conventional example. FIG. In the figure, 1,101 is a channel division circuit, 2.1
02 is a synchronization signal separation circuit, 3.103 is a gate pulse generation circuit, 4,104 is a reference pulse generation circuit, 5.105
is a pulse height data generation circuit, 6.106 is a reference data insertion circuit, 7,107 is a reference data insertion circuit, 8,10
9 is a signal switching circuit, 10B is a memory circuit for one scanning period, 9
, 110 is a field discrimination circuit, 10, 111 is a signal interpolation control circuit, 11, 112 is a reproduction A/D converter, 1
2.113 is a reference pulse selection circuit, 13 and 114 are pulse height data generation circuits, 14.115 is a level correction circuit, and 15 and 116 are reproduction D/A converters. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (2)

[Claims] (1) A characteristic correction device that corrects the characteristics of the signal processing system of each channel when recording and reproducing a video signal divided into a plurality of channels, the device comprising: a reference pulse generating means for generating a plurality of types of reference pulses of different heights corresponding to a black level to a white level; Reference data insertion means for inserting into a ranking period; and signal switching for interpolating a period of a channel in which a fractional part occurs during channel division with a signal pattern of the corresponding period of another channel in which a fractional part does not occur. 1. A characteristic correction device comprising: means for correcting a level of a reproduced video signal using a reference pulse and pulse height data obtained from the reproduced video signal. (2) A characteristic correction device that corrects the characteristics of the signal processing system of each channel when recording and reproducing a video signal divided into a plurality of channels, the device comprising: a reference pulse generating means for generating a plurality of types of reference pulses of different heights corresponding to a black level to a white level; a reference data insertion means for inserting into a ranking period; a storage means for storing a signal pattern of one scanning period in order to interpolate a signal of a period that is a fraction of a channel in which a fractional portion occurs during channel division; a signal switching means for inserting a signal pattern to be interpolated in a period in which the fractional part occurs; A characteristic characterized by comprising: a signal interpolation control means for controlling the readout of the reproduced video signal; and a level correction means for level-correcting the reproduced video signal using a reference pulse and pulse height data obtained from the reproduced video signal. correction device.