JP2644516B2 - Color image signal processing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color image signal processing apparatus for processing a color image signal, and more particularly, to a color image signal for performing a skew compensation process on a color image signal using a delay element. It relates to a processing device.

[Conventional technology]

Conventionally, for example, a delay element called a CCD (Charge Coupled Devise) has been widely used as a means for delaying an analog video signal. In a video tape recorder, a well-known dropout compensation circuit, a cross-section for separating a luminance signal and a chroma signal from a video signal, has been used. It is used for circuits such as shape filters. CCD has the number of stages according to the delay time,
The analog signal input at the sample and hold timing determined by the clock signal fc having a predetermined frequency is sampled and held, and the analog signal is transferred for each stage for a desired time. It is an element that can be delayed.

[Problems to be solved by the invention]

In a CCD as described above, the clock frequency f
Only half the frequency of c, that is, signals in the band lower than the Nyquist frequency can be passed, and when actually used, the sample and hold aperture and CC
A frequency lower than the Nyquist frequency (for example, due to the characteristics of a band-limiting filter that passes before being input to D, and the characteristics of a clock removal filter for removing a clock signal that passes after being output from a CCD, etc.)
(around fc / 3).

On the other hand, in recent years, the bandwidth of a video signal has been widened in accordance with the enhancement of the image quality of a video tape recorder. As described above, if a conventional CCD is adapted to the wideband video signal, the clock signal fc is increased. Come up with the need to raise the frequency.

However, the frequency of the clock signal fc of the CCD can only be increased by about 14 MHz at present, and when an attempt is made to increase the frequency of the clock signal fc, power consumption increases and noise components are likely to occur. A problem arises.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and performs skew compensation processing on a color image signal using a delay element for a narrow-band luminance signal without deteriorating the signal. It is an object of the present invention to provide a color image signal processing device capable of performing the following.

[Means for solving the problem]

The color image signal processing device of the present invention processes a color image signal composed of a color signal having a first frequency band and a luminance signal having a second frequency band including a frequency component higher than the color signal. An apparatus for receiving the luminance signal, separating a first luminance signal including a frequency component equal to or lower than the first frequency band from the inputted luminance signal, outputting the first luminance signal, and outputting the first frequency band. A second luminance signal having a higher frequency component, and a frequency conversion second luminance signal formed by frequency-converting the separated second luminance signal into the first frequency band; The luminance signal output using an output unit and a delay element having a signal pass band through which a signal having the first frequency band can pass and a signal having the second frequency band cannot pass. First skew compensation processing means for performing skew compensation processing on the first luminance signal output from the stage, and a signal having the second frequency band, which is capable of passing the signal having the first frequency band. A skew compensation process is performed on a signal obtained by adding the chrominance signal and the frequency-converted second luminance signal output from the luminance signal output means using a delay element having a signal pass band that cannot pass through Skew compensation processing means.

[Action]

According to the above-described configuration, the broadband luminance signal is frequency-divided, and of the divided luminance signals, the luminance signal in the higher frequency band is frequency-converted into a lower frequency band and added to the chrominance signal, thereby obtaining the broadband luminance signal. The signal is converted into a signal form that can be passed through a narrow-band delay element, and skew compensation processing can be performed.

〔Example〕

 Hereinafter, the present invention will be described using examples of the present invention.

FIG. 1 is a diagram showing a processing circuit as a first embodiment of the present invention.

In FIG. 1, 1 is a video signal input terminal, 2 is a band-limiting filter, 3 is a low-pass filter for separating low-frequency components of the video signal, 4 is a delay line having the same delay time as the 3 filter, 5 is a subtractor for subtracting the output of the filter 3 from the output of the delay line 4, 6 is a frequency converter for converting high-frequency components into low-frequency components, 7 is a CCD delay line from the output of the frequency converter. , A filter for removing the components outside the pass band of the CCD delay line, 8 is a CCD delay line, 9 is a filter for removing the clock component of the output of the CCD delay line, and 10 is a high frequency component converted into a low band again. A frequency converter for converting to a frequency band, 11 is a filter for removing unnecessary components from the output of the 10 frequency converters, 12 is a CCD delay line for passing low frequency components of the video signal, 13 Removes the clock component of the output of the CCD delay line 14 is a delay line for adjusting the time difference with the frequency-converted signal,
Reference numeral 15 denotes an addition circuit for adding the high frequency component and the low frequency component, and 16 denotes a signal output terminal.

In FIG. 1, the video signal input to the terminal 1 is passed through a low-pass filter 2 to remove components outside the required band, then a low-pass filter 3 and a delay 4 Entered on the line. The low pass filter 3 is for extracting a signal component within the pass band of the 12 CCD delay lines, and the delay line 4 has flat amplitude characteristics and delay time characteristics. 3 filters output 12 CC
While being input to the D delay line, it is input to the 5 subtracters.
In the subtractor of 5, the filter output of 3 is subtracted from the output of the delay line of 4 to obtain 12 of the video signals.
High frequency components that cannot pass through the CCD delay line are separated. The high-frequency component output from the subtractor 5 is converted by the frequency converter 6 into a lower frequency that can pass through the CCD delay line 8. After the low-frequency conversion, the high-frequency component passes through a filter of 7 to remove unnecessary components, and then a CCD of 8
Input to the delay line. Here, it is assumed that the delay time of the eight CCD delay lines is substantially equal to the delay time of the twelve CCD delay lines. Since the output of the CCD delay line 8 contains the clock component of the CCD, after removing the clock component by the filter 9, the original high frequency is again output by the frequency converter 10. Is converted to As described above, the obtained high frequency components are input to 15 adders after removing unnecessary components by 11 filters.

On the other hand, the low-frequency component input to the CCD delay line 12 is delayed by a predetermined time, and then the clock component is removed by the filter 13 and input to the delay line 14. The 14 delay lines are used to adjust the time difference between the separated high-frequency component and low-frequency component, whereby the time-aligned high-frequency component and low-frequency component are added to the 15 adders. Has a bandwidth equal to the original signal and is delayed by a predetermined time.
Output to 16 output terminals.

In the first embodiment, the low-pass filter 3, the delay line 4, and the subtracter 5 are used as means for separating the high-frequency component and the low-frequency component. According to this configuration, it is theoretically possible to completely restore the original waveform from the separated high-frequency component and low-frequency component, and the configuration has extremely good waveform reproducibility.

FIG. 2 is a diagram showing a processing circuit as a second embodiment of the present invention. In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 2, reference numeral 17 denotes an input terminal of a chroma signal modulated by a subcarrier, reference numeral 18 denotes an adder for adding a low-frequency-converted luminance signal, and reference numeral 19 denotes a luminance signal from a superimposed luminance signal and a chroma signal. Is a bandpass filter for extracting a chroma signal from the superimposed luminance signal and chroma signal, and 21 is a chroma signal output terminal.

In FIG. 2, the high-frequency component of the luminance signal converted to a low frequency obtained as a filter output of 7 is superimposed on a chroma signal modulated by a sub-carrier input from 17 and by an adder of 18. Is done.

The superimposed luminance signal and chroma signal are delayed for a predetermined time by a CCD delay line of 8, and then a clock component is removed by a filter of 9, and a low pass filter of 19 and 20
Is input to the band pass filter. From the 19 low-pass filters, the luminance signal components are separated and extracted,
Input to 10 frequency converters. From the 20 bandpass filters, chroma signals are separated and taken out and output to 21 terminals.

In the second embodiment, the modulated chroma signal is in a relatively narrow band around the subcarrier, while the high-frequency component of the down-converted luminance signal is in a relatively low band. The delay line for the chroma signal and the high frequency component of the luminance signal can be shared.

FIG. 3 is a diagram showing a processing circuit as a third embodiment of the present invention. In FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 3, reference numeral 22 denotes an input terminal for the RY signal, and reference numeral 23 denotes B
A Y signal input terminal; 24, an adder for adding the BY signal and the high frequency component of the luminance signal; 25, a balanced modulator for modulating the RY signal; 26, a BY signal; Balanced modulator for modulation, 27 is an adder for adding the modulated RY signal and BY signal, 31 is a terminal for inputting a subcarrier signal, and 32 is a terminal for inputting a subcarrier signal.
A terminal for inputting a subcarrier signal having a phase difference of 90 ° with a subcarrier signal input to 31.

FIG. 3 is the same as the first and second embodiments up to the point where only the high-frequency component of the luminance signal input from the input terminal 1 is output from the subtractor 5. Here, in the case of the third embodiment, the color difference signals RY and
, And then input to 26 balanced modulators. In this balanced modulator, the high-frequency component of the luminance signal is low-frequency-converted by performing balanced modulation with the sub-carrier input from 31, and the RY signal is simultaneously AM-modulated. The process is shown in FIG. 5 and FIG. In FIG. 5, A is the third
FIG. 3 shows a spectrum of a luminance signal having passed through the LPF shown in FIG.
The signal of A passes through the LPF of FIG. 3 to separate only low-frequency components as shown in FIG. By subtracting the signal B from the signal A passing through the delay line 4 by a subtracter 5 for time alignment, only the high frequency component is separated as shown in FIG. 5C.

Next, when the RY signal input from the terminal shown in FIG. 3C is added to the signal shown in FIG.
The spectrum is as follows. When the signal D is modulated by the subcarrier fc in the 26 balanced modulators, the state shown in FIG. 6-E is obtained. As is clear from FIG. 6-E, the high-frequency component of the luminance signal is equivalent to a low-frequency conversion by performing balanced modulation with the subcarrier. Here, the unnecessary component generated by the balanced modulation, YH _-2 in FIG. 6-F, is removed by the filter 7 to obtain the high-frequency component of the luminance signal as shown in FIG. 6-F. Then, a signal on which the modulated chroma signal is superimposed can be obtained.

On the other hand, the BY signal input from the terminal 22 is modulated by the sub-carrier input from the terminal 32 in the 25 balanced modulators, and the high-frequency components of the RY and luminance signals are added by the adder 27. The component is added. Here, since the sub-carrier input from 32 has a phase difference of 90 ° with respect to the sub-carrier input from 31, the chrominance signal is in a state of quadrature two-phase modulation.

After passing these superimposed signals through the CCD delay line shown in FIG. 3, the clock component is removed by the filter 9 and the high-frequency component of the luminance signal is extracted by the low-pass filter 19. The chroma signal is separated by a bandpass filter.

As described above, according to the third embodiment, it is possible to share a circuit for modulating a color difference signal and a circuit for converting a high-frequency component of a luminance signal into low-frequency components, thereby simplifying the circuit configuration. Can be.

FIG. 4 is a diagram showing a processing circuit as a fourth embodiment of the present invention. In FIG. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 4, reference numeral 33 denotes a terminal for inputting a chroma signal subjected to quadrature two-phase modulation by a subcarrier, reference numeral 34 denotes an input terminal of a clock for frequency conversion, and reference numeral 36 denotes a terminal for converting a high-frequency component of a luminance signal into a low-frequency signal. A balanced modulator 37 is an adder for adding the modulated chroma signal and the high-frequency signal of the luminance signal converted to the low frequency.

In FIG. 4, only the high-frequency component is separated from the luminance signal input to the terminal 1 as in the first to third embodiments, and the luminance signal is output from the subtractor 5. The high-frequency component is converted into a low-frequency signal by the clock input from 34 in the balance modulator 36, and then added to the chroma signal modulated by the adder 37.

The high frequency component of the luminance signal added to the chroma signal is filtered by a filter 7 to remove unnecessary components, then delayed for a predetermined time by a CCD delay line 8, and after removing a clock component by a filter 9. , Are input to 28 comb filters.

In the 28 comb filter, the high frequency component of the luminance signal and the chroma signal are separated and output to terminals 29 and 30, respectively.

According to the fourth embodiment, by using a comb filter for separating the high frequency component of the luminance signal and the chroma signal, the separation can be performed more ideally, and at the same time, by the comb filter, Line interpolation of chroma signals can be performed.

FIG. 7 is a diagram showing a schematic configuration in a case where the present invention is applied to a skew compensation circuit of a still image reproducing apparatus as a fifth embodiment of the present invention.

In FIG. 7, 46 is a magnetic disk, 47 is a motor for rotating the magnetic disk 46, and 48a and 48b are magnetic disks 46.
Magnetic head for reproducing the still image signal recorded in the
49 is a head switching circuit for switching and outputting a still image signal reproduced by the magnetic heads 48a and 49b, 50 is a system controller for controlling the operation of the apparatus, 51 is a preamplifier, 52 is a preamplifier.
Is a high-pass filter, 53 is a luminance signal system equalizer, 54
Is a luminance signal FM demodulator, 55 is a low-pass filter, 56 is a de-emphasis circuit, 57 is a switch for drop-out compensation, 58 is a low-pass filter for band limitation, 59 is a CCD delay line for one horizontal scanning period (H), 60 is a low-pass filter for removing the clock component of the output of the CCD delay line,
61 is a dropout detector, 62 is an adder for adding a luminance signal delayed by 1H and an undelayed luminance signal to take an average, and 63 is one of an averaged signal and a signal which is not. Switch 64, a low-pass filter for extracting the low frequency components of the luminance signal, 65 a 1 / 2H delay line for skew correction, 66 a temporal signal with the signal output from the 1 / 2H delay line 65. A delay line that delays the input signal for a very short time so that the difference is exactly 1/2 horizontal scanning period, 67 is a delay line with a delay time equal to the low-pass filter 64, and 68 is a subtraction of the low frequency component from the luminance signal Then, a subtracter for extracting only the high-frequency components, 69 is a noise canceller circuit for removing noise components in the high-frequency components of the luminance signal, and 70 is a high-frequency component and a low-frequency component of the luminance signal. Adder for adding the components, 71 is A frequency conversion circuit for converting the high frequency component of the degree signal into a low frequency band, a switch for switching and outputting a signal subjected to skew compensation of 72 and a signal not to be applied, and 73 a frequency conversion circuit for converting to a low frequency band. A low-pass filter for removing unnecessary high-frequency components of the luminance signal, a reference numeral 74 denotes an adder for adding the chroma signal and a high-frequency component of the luminance signal which has been frequency-converted into a low-frequency band, and a reference numeral 75 denotes a color difference line. A low-pass filter for sequentially separating signal components, 76 is a demodulator for demodulating a color-difference line-sequential signal into a baseband signal, 77 is a low-pass filter, 78 is a de-emphasis circuit for a color-difference line-sequential signal, and 79 is a sub-division signal for a color-difference line-sequential signal. A balanced modulator that performs balanced modulation with a carrier wave, 80 is a synchronization circuit that forms a chroma signal by line-homogenizing a chrominance line-sequential signal that has been balanced modulated, and 81 is a skew-compensated signal. A switch for switching and outputting a signal not to be output, 82 is a 1 / 2H delay line for skew compensation, 83 is a time difference from a signal output from the 1 / 2H delay line 82 which is exactly 1/2 horizontal scanning period. Delay line that delays the input signal for a very short time,
A switch for switching between a signal delayed for the horizontal scanning period and a signal delayed for a very short time, 86 is an adder for adding the high-frequency component and the low-frequency component of the luminance signal, and 87 is frequency conversion into a chroma signal and a low-frequency band A comb filter for separating a chroma signal from a signal in which a high-frequency component of a luminance signal is multiplexed with a high-frequency component of a luminance signal which is frequency-converted into a low-frequency band and a chroma signal. Subtracter for subtracting the chroma signal from the signal multiplexed with the luminance signal, and extracting the high frequency component of the luminance signal which has been frequency-converted to the low frequency band, 89 is the luminance which is frequency-converted to the low frequency band A frequency conversion circuit 90 converts the high-frequency component of the signal into the original high-frequency band. A filter, 91 is an output terminal for a broadband luminance signal, 92 is an output terminal for a chroma signal, 93 is an adder for adding the broadband luminance signal and the chroma signal, and 93 is an output terminal for a composite color still image signal. .

Note that the still image reproducing apparatus shown in FIG. 7 records an image signal for one field on one recording track on the magnetic disk 46 at the time of recording, and continuously reproduces the image signal at the time of reproduction. A field recording / reproducing mode for obtaining an image and an image signal of an odd field and an even field are recorded on two adjacent recording tracks on the magnetic disk 46 during recording, and these image signals are alternately switched every one field period during reproduction. The reproduction operation of a still image signal can be performed based on two types of recording and reproduction modes, that is, a frame recording and reproduction mode in which a still image is obtained by reproducing the image.

When a still image signal is recorded on the magnetic disk 46, an index (ID) signal indicating a recording mode at the time of recording is recorded together with the still image signal.
The reproduction operation is performed in a reproduction mode corresponding to the recording mode indicated by the ID signal.

In FIG. 7, the still image reproducing apparatus is loaded with a magnetic disk 46 housed in a jacket (not shown), and that the magnetic disk 46 is loaded at a predetermined position is detected by a disk position detector (not shown). System controller 50
, The system controller 50 instructs the motor 47 to start motor rotation, and the motor 47 drives the magnetic disk 46 to rotate at a predetermined rotation speed.

After the magnetic disk 46 has reached a predetermined number of rotations and is in a stable rotation state, the system controller 50
The magnetic heads 48a and 48b are sequentially traced on each recording track on the magnetic disk 46 by a head moving mechanism (not shown), and for example, an ID signal is extracted from a signal reproduced in each recording track by the magnetic head 48a. It is determined whether the still image signal recorded in the recording track is recorded in the field recording mode or the frame recording mode, and the result is stored in the memory in the system controller 50.

Next, an arbitrary recording track is selected from a plurality of recording tracks formed on the magnetic disk 46 by an operation unit (not shown), and the reproduction operation is started by the system controller 50.
When the system controller 50 is instructed, the system controller 50 gives an instruction to start the head movement to the head moving mechanism, and the magnetic head 48a,
The magnetic head 48a is moved to the recording track position designated by the operation unit, and when the designated recording track position is reached, the movement of the magnetic heads 48a and 48b is stopped.

After moving the magnetic heads 48a and 48b to the designated recording track position as described above, the system controller 50 determines whether the still image signal recorded at the designated recording track position has been recorded in the field recording mode or Whether or not the recording has been performed in the recording mode is confirmed from the determination result of the ID signal stored in the memory in the system controller 50, and according to the type of the recording mode, a head switching circuit is provided.
Control 49 operations.

That is, when the still image signal of the designated recording track is recorded in the field recording mode, the system controller 50 enters the field reproduction mode, and supplies the signal obtained by the magnetic head 48a to the preamplifier 51 at the subsequent stage to perform the designated recording. When the track still image signal is recorded in the frame recording mode, the system controller 50 enters the frame reproduction mode, and outputs the signal obtained by the magnetic head 48a and the signal obtained by the magnetic head 48b every one field period. The operation of the head switching circuit 49 is controlled so that the head switching circuit 49 is supplied to the preamplifier 51 at the subsequent stage.

The still image signal reproduced from the magnetic disk 46 is amplified by the preamplifier 51 as described above, and then the FM signal is modulated by the high-pass filter (HPF) 52 and FM-modulated by the low-pass filter (LPF) 75 Separate color difference line sequential signals.

The FM modulated luminance signal separated by the HPF 52 is equalized by an equalizer 5
After frequency correction at 3, demodulation at FM demodulator 54,
After removing the signal of the excess frequency component by the LPF 55, a day emphasis circuit 56 performs a de-emphasis process having a characteristic opposite to the emphasis performed at the time of recording by the de-emphasis circuit 56, and then supplies the signal to the A side of the switch 57 in the figure. You.

The signal output from the de-emphasis circuit 56 is supplied to a drop-out compensation circuit composed of a switch 57, LPFs 58 and 60, a horizontal scanning period delay line (1HDL) 59, and a drop-out detector 61.

In the drop-out compensation circuit, the luminance signal output from the de-emphasis circuit 56 is normally supplied to the A side of the switch 57 in the figure, and the signal output from the switch 57 is added to the adder 62 and the C side of the switch 63 in the figure. Is supplied as it is, and after passing through the LPF 58, is delayed by the 1 HDL 59 in the horizontal scanning period. Further, through the LPF 60, the switch 57 in FIG.
The switch 57 further supplies a signal to a switch 57. The switch 57 changes the envelope of the FM-modulated luminance signal output from the equalizer 53 by a drop-out detector 61 abruptly (that is, the drop-out). Is connected), the switch 57 is connected to the side B in FIG.
Outputs a luminance signal which is drop-out compensated by the signal 1H before.

The signal output from the switch 57 and the signal 1H before 1H delayed by 1HDL 59 are supplied to the adder 62, and an average signal of both signals is output from the adder 62 to the switch 63. Is supplied to the D side in FIG.

The switch 63 is controlled by the system controller 50 so as to be alternately connected to the C side and the D side in the figure every one vertical scanning period in the field reproduction mode, and to be connected to the C side in the frame reproduction mode in the frame reproduction mode. This improves the image quality in the field reproduction mode.

The output signal of the switch 63 is band-limited by the LPF 64 to a band that can pass through the delay line (1/2 HDL) 65 in the latter half horizontal scanning period, and then the 1/2 HDL 65 and the delay line (△ τDL) Supplied to 66.

The output signal of the switch 63 is supplied to a delay line (DL) 67, where it is delayed for a time equal to the delay time of the LPF 64, and then subtracted by a subtractor 68 to subtract the output signal of the LPF 64. The noise canceling circuit (NC) separates only the high frequency components of the luminance signal from the detector 68.
After removing the noise component at 69, the noise component is supplied to the adder 70 and the frequency conversion circuit 71.

In addition, the adder 70 adds the low-frequency component of the luminance signal output from the LPF 64 and the high-frequency component of the luminance signal from which the noise component output from the NC 69 has been removed, and obtains the luminance having the original frequency band. After the signal is restored, switch 72
Is supplied to the E side in FIG.

On the other hand, the high-frequency component of the luminance signal supplied to the frequency conversion circuit 71 is frequency-converted into a low-frequency band,
Is supplied to the adder 74 via

In addition, the color difference line sequential signal separated from the reproduced still image signal by the LPF 75 is demodulated into a baseband signal by a demodulator 76 and passed through an LPF 77 to an adder 74, which is applied to a de-emphasis circuit 78 at the time of recording. After performing a de-emphasis process having the opposite characteristic to the emphasis, balance modulation is performed by the subcarrier signal in the balance modulation circuit 79, and line synchronization is performed by the synchronization circuit 80 including a comb filter. To form a chroma signal, and the formed chroma signal is supplied to the adder 74 and the G side of the switch 81 in the figure.

Then, the adder 74 adds the high frequency component of the luminance signal frequency-converted to the low frequency band and the chroma signal output from the synchronizing circuit 80, and the signal output from the adder 74 is 1/2 HDL 82 , △ τDL83.

As described above, the low frequency component of the reproduced luminance signal is 1 /
After being delayed by 2HDL65 and △ τDL66, it is supplied to each terminal of the switch 84 as shown, and the high frequency component of the reproduced luminance signal is delayed by 1 / 2HDL82 and △ τDL83 together with the chroma signal, respectively. In the same manner, the connection is supplied to each terminal of the switch 85, and the connection of each switch 84, 85 is alternately switched between the 1/2 HDL65, 82 side and the ΔτDL side every one vertical scanning period, so that the switch 84 is switched. The low frequency component of the compensated luminance signal is supplied to the adder 86, and the switch 86
From 85, a high frequency component and a chroma signal of the luminance signal subjected to skew compensation are output and supplied to the H side of the switch 81 in the figure.

The switches 72 and 81 switch whether or not to perform the skew compensation as described above in accordance with the reproduction mode. The system controller 50 switches the switches 72 and 81 in the field reproduction mode.
To the F side in the figure and the switch 81 to the H side in the figure, and the high frequency components and the chroma signal of the luminance signal subjected to skew compensation as described above are passed through the switch 81. The chroma signal 87 is supplied to the comb filter 87 and the subtractor 88. The comb filter 87 separates only the chroma signal and supplies the chroma signal output terminal 92, the adder 93, and the subtractor 88.

The subtractor 88 subtracts the chroma signal separated by the comb filter 87 from the output signal of the switch 81, and outputs a high frequency component of the luminance signal that has been frequency-converted to a low frequency band.

Then, the high-frequency component of the luminance signal that has been frequency-converted into the low-frequency band output from the subtractor 88 is converted into the original high-frequency band by the frequency
Via the F90, the adder 86 adds the low frequency component of the skew-compensated luminance signal to the original broadband luminance signal, and is connected to the F side in the figure. Luminance signal output terminal 91 via switch 72, adder
Supplied to 93. As described above, the chroma signal separated from the output signal of the switch 81 by the comb filter 87 is supplied to the adder 93 as described above.
A composite color still image signal such as an SC television signal is supplied to an output terminal 94.

As described above, in the field playback mode, the output terminal 9
From 1,92,94, a skew-compensated luminance signal, chroma signal and composite color still image signal are output.

In the frame reproduction mode, the system controller 50 controls the switch 72 to connect to the E side in the figure and the switch 81 to connect to the G side in the figure, and the chroma signal output from the synchronization circuit 80 is switched to the switch 81, The broadband luminance signal supplied to the chroma signal output terminal 92 and the adder 93 via the comb filter 87 is output from the adder 70 via the switch 72 connected to the E side in the drawing. Output terminal 91,
The composite color still image signal is supplied to the output terminal 94 from the adder 93.

As described above, in the frame playback mode, the output terminals 91 and 9
From 2,94, a luminance signal, a chroma signal, and a composite color still image signal without skew compensation are output.

As described above, in the still image reproducing apparatus,
For example, skew compensation performed in the field playback mode
Even when a narrow-band delay line such as a CCD is used, skew compensation can be performed without deteriorating a wide-band luminance signal.

In the fifth embodiment, the skew correction for the high frequency component of the luminance signal is performed by using a narrow band delay line for performing the skew compensation on the chroma signal. It is possible to reduce costs.

In this embodiment, the case where the present invention is applied to a skew correction circuit of a still image reproducing apparatus has been described as an example. However, the present invention is not limited to this, and other embodiments such as a dropout correction circuit and a video tape recorder may be used. The same effect can be obtained when the present invention is applied to a reproducing apparatus, a transmission apparatus, and the like.

〔The invention's effect〕

As described above, according to the present invention, it is possible to perform a skew compensation process on a color image signal using a narrow-band delay element for a broadband luminance signal without deteriorating the signal. It is possible to provide a color image signal processing device that can be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a first embodiment of the present invention. FIG. 2 is a schematic configuration diagram of a second embodiment of the present invention. FIG. 3 is a schematic configuration diagram of a third embodiment of the present invention. FIG. 4 is a schematic configuration diagram of a fourth embodiment of the present invention. 5 and 6 are explanatory diagrams of the operation of the third embodiment of the present invention shown in FIG. FIG. 7 is a schematic configuration diagram showing a case where the present invention is applied to a skew compensation circuit of a still image reproducing apparatus as a fifth embodiment of the present invention. 64 Low pass filter 65,82 1/2 horizontal scanning period delay line 71,89 Frequency conversion circuit 74,86 Adder 79 Balanced modulation circuit 80 Synchronization circuit 87 Comb type Filter 88: Subtractor

Claims (1)

(57) [Claims] An apparatus for processing a color image signal composed of a color signal having a first frequency band and a luminance signal having a second frequency band including a frequency component higher than the color signal. Receiving the luminance signal, separating and outputting a first luminance signal including a frequency component equal to or lower than the first frequency band from the input luminance signal, and outputting a frequency component higher than the first frequency band; A luminance signal output unit that outputs a frequency-converted second luminance signal formed by separating a second luminance signal having the following, and converting the separated second luminance signal into a frequency within the first frequency band; Before being output from the luminance signal output means using a delay element having a signal pass band through which a signal having the first frequency band can pass and a signal having the second frequency band cannot pass. First skew compensation processing means for performing a skew compensation process on the first luminance signal; a signal that allows the signal having the first frequency band to pass therethrough and does not allow the signal having the second frequency band to pass A second skew compensation process is performed on a signal obtained by adding the color signal and the frequency-converted second luminance signal output from the luminance signal output means using a delay element having a pass band.
A color image signal processing device comprising skew compensation processing means.