JPS62222791A - Reproducing device for carrier chrominance signal - Google Patents

Abstract

PURPOSE:To deteriorate a vertical spatial frequency characteristic (vertical resolution) by applying a non-linear characteristic for relatively attenuating a level according to the amplitude of a reproducing carrier chrominance signal in the high frequency component of the vertical spatial frequency of the reproducing carrier chrominance signal in comparison with the low frequency component. CONSTITUTION:The carrier chrominance signal converted in low frequency by a low pass filter 13 and recorded is supplied to a reproducing carrier chrominance signal processing circuit 15 to be the reproducing carrier chrominance signal, supplied to a deemphasis circuit 16 and the complementary characteristic of the vertical spatial frequency to a level characteristic of a preemphasis circuit 5 is applied. Thereby, since the signal is emphasized and recorded by the preemphasis circuit 5 previously provided in a recording system, the S/N is improved in an output terminal 18 and a reproducing color video signal in which the vertical spatial frequency to the level characteristic is not deteriorated is taken out.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a reproduction device for a carrier color signal, and more particularly to a reproduction device that performs de-emphasis on the vertical spatial frequency of a carrier color signal reproduced from a magnetic recording medium.

Conventional technology In a recording and reproducing device such as a VTR, a luminance signal and a carrier color signal are separated from a color video signal to be recorded and reproduced, each is subjected to predetermined signal processing, and then both signals are multiplexed for recording and reproduction. Conventionally, when carrying color signals,
Similar to the luminance signal, line correlation has been used to reduce noise. In other words, the reproduced carrier color signal usually has line correlation, whereas most of the noise mixed in the reproduced carrier color signal has no line correlation. By mixing the signals to extract noise that has no line correlation, and mixing this noise with the reproduced carrier color signal through a limiter, it is possible to extract a reduced reproduced carrier color signal in which the noise is canceled out.

Problems to be Solved by the Invention However, the conventional recording and reproducing apparatus that prevents the above-mentioned noise reduction circuit inputs signal components that have no line correlation as well as noise for reproduced carrier color signals that have no line correlation. Since it is subtracted from the reproduced carrier color signal, there is a problem in that the spatial frequency characteristics in the vertical direction (vertical resolution) deteriorates.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a carrier color signal reproducing apparatus that solves the above-mentioned problems by imparting non-linear characteristics to the vertical spatial frequency of the reproduced carrier color signal.

Means for Solving the Problems The carrier color signal reproducing device of the present invention compares the high frequency component of the vertical spatial frequency of the reproduced carrier color signal with the low frequency component, and This provides a non-linear characteristic that relatively attenuates the level.

The vertical spatial frequency of the active reproduced carrier color signal is given a non-linear de-emphasis characteristic that varies depending on the amplitude. As a result, if there is no line correlation, no de-emphasis characteristic is imparted to the reproduced carrier color signal, and as the line correlation becomes stronger, a greater de-emphasis characteristic is imparted.

Embodiment FIG. 1 includes a block system diagram showing a first embodiment of the apparatus of the present invention together with a recording system. In the figure, the standard television system (NTSC system or PAL system) input to input terminal 1
The color video signal is supplied to a low-pass filter 2 to separate the luminance signal into a P wave, and is supplied to a bandpass filter 3 to separate the carrier chrominance signal! IP waves are sent. The luminance signal is supplied to a recording luminance signal processing circuit 4, where, for example, frequency modulation (
FM), etc. On the other hand, the carrier color signal is supplied to a pre-emphasis circuit 5, where, as will be explained in detail later, pre-emphasis is performed for each signal component appearing vertically on the screen at intervals of one horizontal scanning period (one day). After being given a pre-emphasis characteristic in which the high-frequency components of the spatial frequency in the vertical force direction are relatively enhanced in level compared to the low-frequency components, the signals are supplied to the recording conveyance color signal processing circuit 6, where, for example, the low-frequency components are The frequency of the tongue is converted into a predetermined signal form suitable for magnetic recording and reproduction.

Recording luminance signal processing circuit 4 and recording conveyance color signal processing circuit 6
The luminance signal and the carrier color signal, each converted into a predetermined signal form and taken out, are supplied to a recording amplifier 7, where they are mixed and amplified, and then recorded on a magnetic tape 9 by a recording rotary head 8. Ru.

The reproducing apparatus of this embodiment is an apparatus for reproducing the conveyed color signal recorded as described above, and reproduces the green signal recorded on the magnetic tape 9 using the reproducing rotary head 10, and transmits the reproduced signal to @@
through an amplifier 11 and a high-pass filter 12 . Low pass filter 1
3 respectively. For example, FM
The luminance signal is separated and demodulated by the reproduced luminance signal processing circuit 14 into a luminance signal of the original band. On the other hand, the carrier color signal that has been low-pass-converted and recorded by the low-pass filter 13 is separated into p-waves from the reproduced signal, and this carrier color signal is supplied to the reproduced carrier color signal processing circuit 15, where it also receives the original signal. The signal is returned to the signal form and becomes a reproduced carrier color signal. The reproduced carrier color signal is supplied to a de-emphasis circuit 16;
here! I! This is a characteristic in which the high frequency component of the vertical spatial frequency is relatively attenuated in level compared to the low frequency component, and is complementary to the vertical spatial frequency vs. level characteristic of the pre-emphasis circuit 5. given. Therefore, from the de-emphasis circuit 16, the pre-emphasized reproduced carrier color signal is returned to its original waveform before being pre-emphasized and is taken out and supplied to the mixing circuit 17, where it is sent to the reproduced luminance signal processing circuit 14. It is mixed with the reproduced luminance signal. As a result, a reproduced color video signal with reduced noise components is taken out from the mixing circuit 17 to the output terminal 18.

Here, in this embodiment, since the spatial frequency versus level characteristic in the vertical direction of the screen is de-emphasized by the de-emphasis circuit 16, the S/N of the reproduced carrier color signal is
It can also improve the de-emphasis circuit 1
The vertical spatial frequency versus level characteristics deteriorated by the pre-emphasis circuit 5 installed in the recording system in advance.
Since the signal is emphasized and recorded, a reproduced color video signal with an improved S/N ratio and no deterioration of spatial frequency versus level characteristics in the vertical direction is outputted to the output terminal 18.

Next, an example of an actual flow of the de-emphasis circuit 16 will be described. FIG. 2 shows a block diagram of one embodiment of the de-emphasis circuit 16. In the same figure, the reproduced carrier color signal inputted to the input terminal 20 and returned to the original band is sent to the subtraction circuit 2.
1 and an adder circuit 22, respectively. The reproduced carrier color signal outputted from the subtraction circuit 21 is supplied to an 11-1 delay circuit 23, where it is delayed for 'T:1 horizontal scanning period and then sent to the coefficient circuit 2.
4 by a coefficient N+ (for example, 0.87') and then supplied to the phase adjuster 25. The phase adjuster 25 is 1
If the delay time of 1H can be obtained accurately by the day delay circuit 23, this circuit is unnecessary. However, in reality, the 1H delay circuit 23
The delay time obtained by is not exactly one day, but in this case, if the output signal of the coefficient circuit 24 is supplied to the subtraction circuit 21 without performing phase adjustment and the subtraction operation is performed with the input reproduced carrier color signal, the equivalent delay time is Since it operates so that the coefficient N1 becomes small, the desired de-emphasis characteristic cannot be obtained.

Therefore, by adjusting the phase of the output signal of the coefficient circuit 24 using the phase adjuster 25 so that it becomes the same as the phase of the reproduced carrier color signal delayed by one day, the desired de-emphasis characteristic can be obtained.

The subtraction circuit 21 performs a subtraction operation of subtracting the output signal of the phase adjuster 25 from the reproduced carrier color signal from the input terminal 20. Here, as is well known, the color subcarrier frequency of the carrier color signal in the NTSC system is 227.5 times the horizontal scanning frequency, and due to the fraction of 05, the color subcarrier frequency is in phase at the beginning and end of 1). are different by 0.5 period, that is, 180°. Therefore, if the carrier color signal extracted by the phase adjuster 25 after being delayed by 1H is line-correlated with the reproduced carrier color signal input from the input terminal 20, the carrier color signal is in an opposite phase relationship with the subtractor circuit. From 21, a reproduced carrier color signal which is substantially the antecedent to the immediately preceding reproduced carrier color signal is taken out. The output reproduced carrier color signal of the subtraction circuit 21 is supplied to the 11'' delay circuit 23, while the coefficient circuit 26
Here, the signal is multiplied by a coefficient N2 (for example, 0.13) and is supplied to the subtraction circuit 22 through the post-IC phase adjuster 27.

The subtraction circuit 22 subtracts the reproduced carrier color signal from the input terminal 20 with the signal from the phase adjuster 27 whose level is so high that there is no line correlation, and the difference signal obtained by this is sent to the non-linear circuit. 28. The non-linear circuit 28 is, for example, an amplitude limiter that limits the amplitude of the input signal to a constant value, and allows input signals with an amplitude smaller than this constant value to pass through with the same amplitude, and passes input signals with an amplitude larger than this constant value. The input signal is configured to be output after being limited to this constant value.

The difference signal taken out from the non-linear circuit 28 is sent to the coefficient circuit 29.
where the coefficient N3 (e.g. 0.57)
After being multiplied by , the signal is supplied to the subtraction circuit 3o. Subtraction circuit 3
0 is the coefficient circuit 2 from the reproduced carrier color signal from the input terminal 20.
A subtraction operation is performed to subtract the output difference signal of 9, thereby outputting the q signal to the output terminal 31.

The signal output to this output terminal 31 is given a de-emphasis characteristic in which the high-frequency component of the spatial frequency in the vertical direction of the screen of the input reproduced carrier color signal is relatively attenuated in level compared to the low-frequency component. This is a reproduced carrier color signal, and the reproduced carrier color signal is given a non-linear de-emphasis characteristic in which the larger the amplitude, the smaller the de-emphasis is.

FIG. 3 shows a block system diagram of an embodiment of a circuit in which a pre-emphasis circuit and a de-emphasis circuit are each constructed using a common circuit. First, to explain the operation during playback, during playback, switches 36, 38, 49 and 50
are respectively switched and connected to the contact P side. As a result, the reproduced carrier color signal entering the input terminal 35 is transferred to the switch 36. Subtraction circuit 39.11-1 delay circuit 40. is supplied to the subtraction circuit 39 through a coefficient circuit 41 and a phase adjuster 42, respectively;
Here, the reproduced carrier color signal from switch 36 after 1H is subtracted. The output signal of the subtraction circuit 39 is sent to the 1H delay circuit 4.
0, and is supplied to a subtraction circuit 45 through a coefficient circuit 43 and a phase adjuster 44, where switch 3
After being subtracted with the reproduced carrier color signal from switch 36, the signal is further supplied to a subtraction circuit 48 through a non-linear circuit 46 and a coefficient circuit 47, where it is subtracted from the reproduced carrier color signal from switch 36.

Therefore, from the subtraction circuit 48, a reproduced carrier color signal to which a non-linear de-emphasis characteristic has been added is taken out, similar to the output signal of the subtraction circuit 30 shown in FIG.
It is output to the output terminal 51 through 0. According to this embodiment, by providing the non-linear circuit 46, it is possible to reduce the proportion of the de-emphasis circuit that cannot restore the original waveform (for example, the gain of the stationary amplifier 37 is
However, there is only a deviation of 1/G).

On the other hand, during recording, the switches 36, 38, 49 and 50 are connected to the contact R side, respectively. As a result, the input terminal 35
The carrier color signal inputted to the switch 36 and the differential amplifier 3
7. Switch 38. Subtraction circuit 39.18 Delay circuit 40.
The signal is supplied to three subtraction circuits through a coefficient circuit 41 and a phase adjuster 42. The carrier color signals taken out from these three subtraction circuits are supplied to a 1H delay circuit 40, and are also supplied to a subtraction circuit 45 through a coefficient circuit 431 and a phase adjuster 44, where the carrier color signals from the switch 38 are supplied. and reduced σ
After that, it is supplied to the non-linear circuit 46.

The non-linear circuit 46 extracts the output carrier color signal of the subtraction circuit 45 with the amplitude of a portion larger than a constant value being limited in amplitude.
Furthermore, it is supplied to a subtraction circuit 48 through a coefficient circuit 47, where it is subtracted from the carrier color signal from switch 38. This circuit has a pre-emphasis characteristic that is the opposite of that by inserting a de-emphasis circuit during playback into the feedback loop. Therefore, the signal outputted from the differential amplifier 37 to the output terminal 51 through the switch 50 becomes a nonlinear preemphasized carrier color signal.

In addition, each coefficient 01゜02 of coefficient circuits 41, 43 and 47
and 03 are, for example, 0.87, 0.13 and 0.03, respectively.
Selected as 51st.

In the above embodiment, the de-emphasis circuit having the configuration shown in FIG. 2 is placed in the feedback loop of the differential amplifier 37 to obtain the pre-emphasis characteristic. It may also be used to obtain de-emphasis characteristics.

In each of the embodiments shown in FIGS. 2 and 3, input signals past the output time are weighted and summed, and the input signal is obtained by adding weights to the input information, and the output information at the output time is weighted to the input signal. This is a forward type (cyclic type) de-emphasis circuit that synthesizes and outputs the respective signals.

On the other hand, the de-emphasis circuit described below is
A de-emphasis circuit 56 in the second embodiment of the device of the present invention shown in FIG. 4 is constituted by a transversal filter of only a backward type or a combination of a backward type and a forward type.

In Fig. 4, the same components as in Fig. 1 are given the same reference numerals.
The explanation will be omitted. The delay circuit 53 is a circuit for delaying the luminance signal by the time delay caused by the pre-emphasis circuit 54 and aligning it with the pre-emphasized carrier color signal. This is a circuit for delaying the reproduced luminance signal by the amount of delay and adjusting the time with the de-emphasized reproduced carrier color signal.

The pre-emphasis circuit 54 is a backward-type pre-emphasis circuit or a combination of a backward-type and a forward-type pre-emphasis circuit that outputs a high-frequency component of a vertical spatial frequency with a relatively enhanced level compared to a low-frequency component. On the other hand, the de-emphasis circuit 56 has a characteristic of outputting the high-frequency component of the vertical spatial frequency of the reproduced carrier color signal with the level attenuated relatively compared to the low-frequency component, and the pre-emphasis circuit 54 This is a de-emphasis circuit that has spatial frequency versus level characteristics in the vertical direction that are complementary to that of the de-emphasis circuit, and is composed of a bankward type or a combination of a backward type and a forward type.

Next, the fifth embodiment of the de-emphasis circuit 56 will be described.
This will be explained with reference to FIGS. 9 to 9. FIG. 5t shows a block diagram of a first embodiment of the de-emphasis circuit 56. In the same figure, the reproduced carrier color signal inputted to the input terminal 60 is supplied to n delay circuits 611 to 61n connected in cascade, while the coefficient circuit 621 with coefficient (-1) TI-kn and the phase Tune! The signals are supplied to the adder circuit 64 through the iW devices 631, respectively.

Delay circuits 611 each having a delay time of 1H, for example.
Each output reproduced carrier color signal of ~61η-1 is sent to the coefficient circuit 62.
2 to 621 and phase adjusters 632 to 63Tl, respectively, to the adder circuit 64. Also, the final stage delay circuit 6
The reproduced carrier color signal extracted with a nil delay from 11 is multiplied by a positive coefficient 1o by a coefficient circuit 621 (1) and then supplied to an antecedent circuit 64 and then supplied to a force coefficient circuit 67. Each of the output reproduction carrier color signals of the circuits 621 to 621 is set relative to the main signal among the coefficient circuits 621 to 62Tl so that the reproduction carrier color signals output from the coefficient circuits 621 to 621 are approximately in phase with the phase of the output reproduction carrier color signal (main signal) of the coefficient circuit 62. A coefficient circuit to which a reproduced delayed carrier color signal whose delay time difference is an odd multiple of 1H is supplied is selected to have a negative coefficient value, and 11
The coefficient circuits to which the delayed reproduction carrier color signal, which is an even multiple of '', are supplied are each selected to have a positive coefficient value. Further, the phase adjusters 631 to E) 3TI perform phase adjustment so that they are completely in phase or in opposite phase, respectively, with the main signal as a reference.

From the addition circuit 64, a signal with a waveform as if the spatial frequency components in the screen vertical direction of the input reproduced carrier color signal were integrated is taken out, and this signal is added through a nonlinear circuit 65 having the same configuration as the nonlinear circuit 28. The signal is supplied to a circuit 66 where it is weighted by a coefficient circuit 67 with the n-day delayed reproduced carrier color signal multiplied by a positive coefficient "1" before being outputted to an output terminal 68.

As a result, the reproduced carrier color signal whose vertical spatial frequency has been non-linearly de-emphasized as described with reference to FIG. 2 is outputted to the output terminal 68. This embodiment is a backward-type digital signal that obtains a de-emphasized reproduced carrier color signal by adding and combining temporally future reproduced carrier color signals with respect to the main signal at the time of output using a weighting factor ζJ. It is an emphasis circuit, and is also an output addition Φ type and acyclic type.

Next, FIG. 6 shows a block diagram of a second embodiment of the de-emphasis circuit 56. In the figure, the same components as those in FIG. 5 are denoted by the same reference numerals, and the explanation thereof will be omitted. Input terminal 6
The reproduced carrier color signal inputted in 6 is passed through a coefficient circuit 70+ which multiplies a negative coefficient - and O to a delay circuit 7 as a main signal.
21, and the coefficients e+, -f12. ...
(1) Coefficient circuits 702 and 703 that multiply Tln no η,
..., 70 Tsukuda and phase adjuster 71+, 712,...
..., through 711, adder circuit 73+, 732,...
..., 731. Each output signal of the delay circuits 721 to 72η having a delay time of 1H is sent to the adder circuits 731 to 72η.
731 respectively.

As a result, a carrier color signal having a waveform as if vertical spatial frequency components of the input reproduced carrier color signal were integrated is taken out from the adder circuit 73Tl, and passed through the adder circuit 73Tl to the nonlinear circuit 74 having the same configuration as the nonlinear circuit 65. supplied to The adder circuit 75 adds a positive coefficient L1 to the reproduced carrier color signal extracted after being delayed by nH from the final stage delay circuit 61Tl.
The reproduced carrier color signal inputted through the coefficient circuit 76 and the phase adjuster 77 and the output signal of the non-linear circuit 74 are added and synthesized, respectively, to produce a reproduced signal imparted with the non-linear de-emphasis characteristic. A carrier color signal is generated and outputted to the output terminal 68. This embodiment is an input weighted backward de-emphasis circuit.

Incidentally, the delay circuits 61+ to 61η in FIG. 6 can also be constituted by one delay circuit having a delay time of nl-1 (the same applies to FIG. 5).

Next, FIG. 7 shows a block diagram of a third embodiment of the de-emphasis circuit 56. In the figure, the same components as those in FIG. 6 are denoted by the same reference numerals, and the explanation thereof will be omitted. Like the second embodiment shown in FIG. 6, this embodiment is of the input weighted type and is of the backward type. This de-emphasis circuit differs from the second embodiment in the location where the main signal is sent. In FIG. 7, the reproduction carrier color signal which has been delayed by a total of nHW and taken out from the delay circuit 61Tl is supplied to coefficient circuits 81 and 76, respectively, and after being multiplied by a negative coefficient -LO by the coefficient circuit 81, the reproduced carrier color signal is outputted from the delay circuit 61Tl and is then multiplied by a negative coefficient -LO. It is supplied as an 80-head main signal. The adder circuit 80 adds and synthesizes the signal from the adder circuit 73η and the above-mentioned main signal, outputs a signal with a waveform in which spatial frequency components in the vertical direction are integrated, and adds the signals through the non-linear circuit 74. Supplied to circuit 75.

Next, FIG. 8 shows a block diagram of a fourth embodiment of the de-emphasis circuit 56. In the figure, the same components as those in FIG. 5 are denoted by the same reference numerals, and the explanation thereof will be omitted. However, in reality, the coefficient circuits 621 to 62 T+n etc. 86 in FIG.
Each coefficient (-1) of 1 to 86Tl "Cη~-e+, lo
and each coefficient (
-1) Tl之η〜-fly.

1-0 are mutually different values. This embodiment is an output weighted type which is a combination of a forward type and a backward type, and is an acyclic type de-emphasis circuit. For example, delay circuits 85+ to 85 each have a delay time of 1H.
1. The coefficient circuits 861 to 86Tl and the phase adjusters 871 to 87t+, to which the output reproduced carrier color signals are supplied, together with the adder circuit 88 constitute a forward type de-emphasis circuit section.

The adder circuit 88 receives the main signal taken out from the coefficient circuit 62ηf1, each reproduced carrier color signal from the phase adjusters 631 to 63Tl, which is input information in the temporal future with respect to the main signal, and the main signal. By adding and combining the reproduced carrier color signals of the phase adjusters 871 to 87Tl, which are temporally past input information, respectively, a waveform ( This example uses forward type and back 1 node q
ll, the signal is integrated before and after the edge), and this signal is passed through a non-linear circuit 89 having the same configuration as the non-linear circuit 65 to an adder circuit 90.
Output to. The adder circuit 90 is a coefficient circuit 91 that multiplies the reproduced carrier color signal taken out from the delay circuit 611 by a coefficient L+.
The reproduced carrier color signal from the output terminal 68 and the signal from the non-linear circuit 89 are added and synthesized, respectively, and an emphasized reproduced carrier color signal is outputted to an output terminal 68.

Next, a fifth embodiment of the pre-emphasis circuit 56 will be described with reference to FIG. In the figure, the same components as those in FIGS. 2 and 5 are marked with the same symbol, and their explanation will be omitted. In FIG. 9, the reproduced carrier color signal from the input terminal 20 is added and combined with the signal from the phase adjuster 27 in an adder circuit 93 to form a reproduced carrier color signal with linear de-emphasis characteristics, and then delayed. It is supplied to a circuit 611 and a coefficient circuit 621, respectively. This embodiment is an output weighted de-emphasis circuit which is a combination of a backward type and a forward type, similar to the de-emphasis circuit shown in FIG. 8, but the cyclic type shown in FIG. The difference from FIG. 8 is that the basic components of the de-emphasis circuit shown in FIG. This embodiment can also obtain the same non-linear de-emphasis characteristic as in FIG.

In addition, in FIG. 9, the connection order of the cyclic de-emphasis circuit section and the backward-type de-emphasis circuit section may be reversed.

The relationship between the format of each embodiment of the de-emphasis circuit in the device of the present invention described above and the figure number showing the embodiment corresponding to the format is summarized as shown in the following table.

Although the de-emphasis circuits shown in blank spaces in the above table are not shown, these circuits are also included in the device of the present invention. For example, by connecting the circuit shown in FIG. 2 and the circuit shown in FIG. 5 in series, an output weighted de-emphasis circuit consisting of a combination of an acyclic type and a cyclic type can be constructed.

Note that the present invention is not limited to the above embodiments; for example, although the phase adjuster is provided on the output side of the coefficient circuit in all the embodiments, it may also be provided on the input side of the coefficient circuit, and the phase adjuster may be provided on the input side of the coefficient circuit. Circuits 611-61T+.

The delay times of 721 to 72Tl, 85+, and 85Tl may be arbitrary as long as they are a natural number multiple of 1H. However, in this case, the coefficient circuit 621-62T1.702-70T168
The sign of each coefficient of 61 to 86η needs to be selected so as to have a predetermined phase relationship with respect to the main signal.

In addition, we have explained the case where the de-emphasis circuit uses as an input signal the reproduced carrier color signal which is returned to the original band after a minute taP wave from the reproduced signal. It is also possible to use a carrier color signal as an input signal.

In this case, since de-emphasis is performed on the carrier color signal that has been low-band converted and has a color subcarrier frequency of 629kHz, for example, the carrier color signal (N
In the case of TSC method, color subcarrier frequency is 3.58 MHz
), a phase adjuster for adjusting the phases of the two human input signals in the adder/subtracter circuit, which is required when performing de-emphasis on the signal (), becomes unnecessary. This is because a delay circuit is installed in the de-emphasis circuit, and the delay circuit usually has a slight error from the predetermined delay time. The phase change of the output signal of the delay circuit occurs when the color subcarrier frequency is, for example, 3.
The color DI'm
This is because the number is much smaller when a low frequency converted carrier color signal is inputted, for example, when the transmission frequency is 1329k)-12. Furthermore, as a result, waveform restorability can be more improved when de-emphasis is performed on the low-pass converted carrier color signal than when de-emphasis is performed on the carrier color signal.

Furthermore, although the above embodiment has been described with respect to the case where a carrier color signal of the NTSC system is de-emphasized, the present invention can also be applied to a carrier color signal of the PAL system. However, in this case, in the carrier color signal of the PAL system, the phase of the color subcarrier of one of the two color difference signals is inverted every day, so the delay circuit 23.40.61+
~611°72+~72Tl and 85t~851 are each configured to have a delay time that is a natural number multiple of 2H.

Furthermore, since the carrier color signal in the PAL system undergoes phase inversion with a delay of 2 days or an odd multiple thereof, the n used for each coefficient in the coefficient circuit means that the coefficient circuit is 2 days relative to the main signal.
This indicates that the path has a delay time difference of nH. Also, the nonlinear circuits 28.46.65, 74.89 are
The present invention is not limited to the imaging width limiter.

Effects of the Invention As described above, according to the present invention, since non-linear de-emphasis is performed on the vertical spatial frequency of the reproduced carrier color signal during reproduction, there is little deterioration in vertical resolution and the S/N of the reproduced carrier color signal is reduced. In addition, the de-emphasis factor can be made smaller when there is no correlation in the vertical direction of the reproduced carrier color signals, so it is possible to It has the advantage of being able to reproduce the original signal waveform even through a linear de-emphasis circuit with almost no practical problems.

[Brief explanation of drawings]

1 and 4 are block system diagrams showing each embodiment of the apparatus of the present invention together with a recording system, and FIG. 2 is a block system diagram of an embodiment of the de-emphasis circuit in the block system shown in FIG. FIG. 3 is a block system diagram of an embodiment in which a pre-emphasis circuit and a de-emphasis circuit are shared, and FIGS. 5 to 9 each show an embodiment of the de-emphasis circuit in the block system shown in FIG. 4. It is a block system diagram. 16.56... De-emphasis circuit, 20°60.
...Reproduction transport color signal input terminal, 23.40...1Ha
Extension circuit, 28, 46.65.74.89...Non-linear circuit, 37...Differential amplifier, to 611□61n. 72+ to 72n, 85+ to 85n...delay circuits. Figure 1 Figure 2 ¥4y

Claims (1)

[Claims] In a carrier color signal reproducing device for obtaining a reproduced carrier color signal in the original signal form from a reproduced signal reproduced from a recording medium,
By comparing the high-frequency component of the spatial frequency in the vertical direction to the low-frequency component of the reproduced carrier color signal, a non-linear characteristic is imparted to the reproduced carrier color signal in which the level is relatively attenuated according to the amplitude of the reproduced carrier color signal. Features: Reproducing device for carrier color signals.