JP2744287B2 - Image signal playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for recording an image signal for one screen having a luminance component signal and a color component signal,
The present invention relates to an image signal reproducing apparatus that reproduces an image signal from a recording medium recorded in a state where at least one of the color component signals is divided into a plurality of areas.

[Conventional technology]

2. Description of the Related Art Conventionally, a still video device, for example, is known as one of recording and reproducing devices for recording an image signal on a recording medium such as a magnetic disk and reproducing the image signal.

In such a still video device, an image signal is separated into a luminance signal and two types of color difference signals, and then each is separated into FM signals.
After the modulation, the recording / reproducing method of recording and reproducing the chrominance signal with respect to the luminance signal alternately in one band at a time in one horizontal synchronization period to another band, that is, recording and reproducing in a chrominance line sequential state is adopted. Have been.

[Problems to be solved by the invention]

However, the recording system used in the above-described still video apparatus has the following disadvantages.

A luminance signal (Y signal) and a chrominance signal (RY signal or B signal)
-Y signal) is frequency-multiplexed and recorded after being FM-modulated, so that if the luminance signal band is increased to about 7 MHz to 8 MHz, the frequency band over which the magnetic recording medium can be recorded is exceeded. At the moment,
The limit is around 4.5MHz.

Since the Y signal and the RY or BY signal are each subjected to frequency modulation after being FM-modulated,
Intermodulation distortion between the Y signal and the RY or BY signal is likely to occur. For example, if the FM modulation carrier frequency of the Y signal is f _Y (MHz), and the FM modulation carrier frequencies of the RY and BY signals are f _C (MHz), f _Y −f _C and f _Y −2f _{C are} obtained. Frequency distortion is particularly problematic.

Also, the vertical resolution of the Y signal, that is, the number of scanning lines is limited to 525 due to the restrictions of the television system.
Since the -Y or BY signal is frequency-multiplexed and recorded with the Y signal in a color difference line-sequential state, the resolution of the color in the vertical direction is low.

Therefore, in view of the above, it is an object of the present invention to be able to satisfactorily reproduce a luminance component signal from a recording medium on which a luminance component signal having a wide frequency band is recorded. The image signal can be reproduced from the recording medium without being affected by the distortion caused by the intermodulation with the signal, and the image signal can be restored without being affected by the dropout that occurs when the recording medium is reproduced. An object of the present invention is to provide an image signal reproducing apparatus configured to be able to perform the processing.

[Means for solving the problem]

The image signal reproducing apparatus of the present invention, when recording an image signal for one screen having a luminance component signal and a color component signal,
An apparatus that reproduces an image signal from a recording medium that is recorded in a state in which at least one of the luminance component signal and the color component signal is divided into a plurality of areas, and is recorded on the recording medium. Reproducing means for reproducing the luminance component signal and the color component signal, and outputting the respective signals in predetermined units, and whether a dropout has occurred in the signal output in predetermined units from the reproducing means. Drop-out detection means for detecting whether or not a part of the luminance component signal and the color component signal output for each predetermined unit from the reproduction means are detected by the drop-out detection means. Storage means for converting the luminance component signal and the color component signal into separate storage areas, respectively; When the signal and the color component signal are read and the original image signal for one screen is reconstructed, the index signal is subjected to dropout compensation processing for a signal indicating that dropout has occurred. And output control means for outputting from

[Action]

With the above-described configuration, a part of the reproduced luminance component signal and color component signal is converted into an index signal indicating whether or not dropout has occurred, and then the luminance component signal and the color component signal are separately separated. Since the luminance component signal and the color component signal once stored are read out and the image signal for the original one screen is reconstructed, dropout of the index signal occurs. The signal indicating that the signal has been output is subjected to a drop-out compensation process and then output, so that the image signal can be restored without being affected by the drop-out that occurs during reproduction of the recording medium.

〔Example〕

 Hereinafter, the present invention will be described in detail based on examples.

FIG. 1 is a recording system block diagram of a still video apparatus to which the present invention is applied as one embodiment of the present invention. In this figure, 2 is a luminance signal input terminal, 4 is a clamp circuit, 6 is an emphasis circuit, 8 is an FM modulation circuit, 10 is an adder that multiplexes an ID signal to be described later on an FM-modulated luminance signal, and 12A and 12B are Switching switches, 14, 16, 18, and 20 are recording amplifiers, 2
2, 24, 26, and 28 are magnetic heads, 29 is a head moving mechanism, 30 is a disk-shaped magnetic recording medium (magnetic disk), 32 is a center core on the magnetic disk 30, and 34 is provided on a center core 32. A PG pin (magnet for detecting the rotational phase of the magnetic disk 30), 36 is a PG coil for detecting the position of the PG pin 34 using the electromagnetic induction effect, 38 is a spindle motor for rotating the magnetic disk, 40 is A spindle motor control circuit that controls the rotation speed and phase of the magnetic disk 30 by referring to the vertical synchronization signal of the input video signal and a PG pulse described later. 42 introduces a weak PG pin detection signal detected by the PG coil 36. A PG pulse generator for generating a PG pulse of a predetermined level. Reference numeral 44 denotes a system controller, which controls the switching of the switching switches 12A and 12B or the recording amplifier 1
The recording operation control of 4, 16, 18, and 20 is performed. Reference numeral 46 denotes an ID modulator which performs a predetermined modulation on a recording carrier of an ID (to be described later in detail) based on the recording mode data given from the system controller 44. Reference numeral 48 denotes a synchronization separation circuit, which separates the composite synchronization signal from the luminance signal with the composite synchronization signal.
50 is a clamp pulse generator, and 52 is a vertical synchronizing signal generation circuit. 54 is an input terminal for the color difference signal RY, 56 is a clamp circuit, 58 is an emphasis circuit, 60 is an FM modulation circuit, and 62 is FM.
A band-pass filter (BPF) that passes only a predetermined band of the modulated RY signal, 66 is an input terminal of the color difference signal BY, 68 is a clamp circuit, 70 is an emphasis circuit, and 72 is FM.
A modulation circuit 74 is a band-pass filter (BPF) that passes only a predetermined band of the FM-modulated BY signal. 64 is F
This is an adder for frequency-multiplexing the M-modulated RY signal and BY signal. Reference numeral 76 denotes a PLL circuit for generating an ID carrier having a frequency 13 times the horizontal synchronization frequency.

FIGS. 2A to 2C are flow charts showing the operation of the recording system block diagram shown in FIG. 1, and are composed of steps S2 to S148.

The operation of the recording system block (FIG. 1) will be described in detail below with reference to the flowchart and other accompanying drawings.

In this embodiment, the video signal to be recorded is
Any of a composite video signal such as an NTSC television signal or a component video signal such as an RGB signal may be used, but in the following description, a luminance signal with a composite synchronizing signal that has been subjected to predetermined processing will be described. Y), the case where color difference signals RY and BY are input, recorded and reproduced.

The luminance signal Y as described above is input to the input terminal 2, is clamped by the clamp circuit 4, is subjected to a predetermined emphasis process, and is FM-modulated by the FM modulation circuit 8. The frequency arrangement at this time is assumed to conform to the steel video flop standard specified by EIAJ with a sync tip of 6 MHz and a white peak of 7.5 MHz, for example, as shown in FIG. 3 (A). By performing FM modulation in this way, compatibility with conventional devices is maintained and there is no need to frequency multiplex the color information signal.
There is no need to remove the sideband using a BPF or the like, and the band after modulation becomes wider than before. If the compatibility with the conventional device is not considered, the modulation can be performed so as to take a wider band without being limited to this, and the horizontal resolution of the luminance signal can be increased.

The FM modulated wave is sent to the adder 10, where the ID signal based on the above-mentioned still video flop standard is frequency-multiplexed.

Note that a 3-bit identification code is assigned to the user's area of the ID signal. The contents are, for example, one bit for black / white discrimination and two bits for recording mode discrimination as shown in FIG. That is, regarding the bit for black / white / color discrimination, the color is set to "1" and the black and white is set to "0". As for the recording mode discriminating bit, when the bit is “00”, the field recording mode is set.
At the time of the frame recording mode, at "10" the first high-definition recording mode (described later), and at "11" the second high-definition recording mode (described later).

First, the operation of the monochrome recording mode will be described with reference to the flowchart.

When recording is to be performed in the field recording mode in the black and white recording mode, the operator instructs the system controller 44 (see FIG. 1) to that effect through the operation unit 82 (steps S2 and S4). The system controller 44 gives an instruction to the ID modulator 46 based on this information, and is output from the PLL circuit 76 so that a code "00" (see FIG. 8) indicating field recording is set in the user's area of the ID signal. ID
The carrier is modulated and multiplexed with the luminance signal FM-modulated in the adder 10 (step S6). Further, the switching switch 12A is controlled, the contacts a and c are connected, and the FM modulation circuits 60 and 70 for the color difference signals are muted (step S).
8). Then, it waits for a recording operation start command.

Then, when the operator instructs the start of recording by the operation unit 82, the system controller 44 sends a recording gate signal to the recording amplifier 14, and maintains a predetermined phase relationship with the PG pin 34 so as to maintain the brightness of one field on the magnetic disk 30. The signal Y is recorded for one track (step S14). However, prior to such recording, it is assumed that the steel video flop holding the magnetic disk 30 therein is already loaded in the main body of the recording apparatus, and furthermore, based on the luminance signal input to the luminance signal input terminal 2, Sync separation circuit 48, vertical sync signal generation circuit 52
The vertical sync signal obtained via the PG detection coil 36
And a PG pulse obtained from a PG pulse generator 42.The spindle motor control circuit 40 controls the spindle motor 38 so that the magnetic disk 30 rotates at a predetermined rotation speed.
Is driven, and as a result, the magnetic disk 30 is rotated at a predetermined rotation speed (steps S10 and S12).

FIG. 5A schematically shows a recording track pattern on the magnetic disk 30 as a result of recording of one track (corresponding to one field) as described above.
become that way. That is, the recording track Y ₁ outer shown in this figure is a tiger arrive pattern formed by the above-mentioned recording operation.

Subsequently, when recording is performed in the black and white field recording mode for the second field, recording for one track is performed inside the recording, as shown in FIG. 5 (A).

Next, the monochrome frame recording mode will be described. In this case as well, the operator similarly instructs the black and white frame recording mode using the operation unit 82, and the system controller 44 is notified of that (steps S2, S4, S16). The system controller 44 gives an instruction to the ID modulator 46, modulates the ID carrier output from the PLL circuit 76 so that the code "01" (see FIG. 8) representing the outer track is set in the ID signal, and adds the ID carrier. The signal is sent to the device 10 and multiplexed with the FM-modulated luminance signal (steps S18, S20, S22). Further, the switching switch 12A is controlled to make the contacts a and c connected (step S24), and waits for a recording operation start command.

When the operator instructs the start of recording by the operation unit 82, the system controller 44 controls the spindle motor 38 to rotate at a constant speed (steps S26 and S28), and thereafter sends a recording gate signal to the recording amplifier 14, and The first field (Y ₁ ) is recorded on the disk 30 (step S3
0). When this recording is completed, the system controller 44
Again gives an instruction to the ID modulator 46, this time setting the PLL so that "10" (indicating the inner track in the frame recording mode; see FIG. 8) is set in the user area of the ID signal.
The ID carrier output from the circuit 76 is modulated and multiplexed with the luminance signal modulated by the FM in the adder 10 (step S32,
S20, S22).

Next, the system controller 44 switches the switching switch 12.
A is controlled to connect the contacts a and d (step S24). At this time, since the spindle motor 38 has already been rotating at a constant speed, the recording gate signal is immediately sent to the recording amplifier 16, and
Subsequently, the second field (Y ₂ ) is recorded (steps S26, S28, S30). As a result, the recording track patterns recorded on the magnetic disk 30 are the tracks Y ₁ and Y ₂ from the outside as shown in FIG. 5 (B).

Subsequently, when recording is performed in the monochrome frame recording mode for the second frame, as shown in FIG. 5B, a new track is placed inside the two tracks already recorded.
Y ₁ and Y ₂ are formed. When performing the recording in the second frame, the magnetic heads 22 and 24 are temporarily moved by the head moving mechanism 29, and the same recording amplifiers 14 and 16 as those in the first frame may be used. In addition, without moving such a magnetic head,
It is also possible to use third and fourth magnetic heads 26, 28 and their corresponding recording amplifiers 18, 20.

Next, a case where recording is performed in the high-definition recording mode at the time of monochrome recording will be described. Also in this case, the operator instructs the mode by the operation unit 82 and notifies the system controller 44 of the instruction (steps S2, S4, S16, S34).

The system controller 44 gives an instruction to the ID modulator 44,
Code "11" indicating the mode in the user area of the ID signal
The ID carrier output from the PLL circuit 76 is modulated so that (see FIG. 8) is set, and the adder 10 multiplexes the modulated ID carrier with the FM-modulated luminance signal (steps S36, S38, S40).

Next, the system controller 44 switches the switch 12A.
Is controlled to connect the contacts a and c (step S42).
Then, it waits for a command to start the recording operation.

When the operator instructs the start of recording by the operation unit 82, the system controller 44 rotates the spindle motor 38 at a constant speed (steps S44 and S46), and then sends a recording gate signal to the first recording amplifier 14, and the magnetic disk 30 The first field (Y ₁ ) is recorded on the upper side (step S48).

When this recording is completed, the system controller 44
An instruction is given to the ID modulator 44 to change the two bits for recording mode discrimination in the user's area of the signal to "10" (see FIG. 8) (step S40), and then the contacts a and d of the switching switch 12 are connected. (Step S42). Thereafter, the recording gate signal is immediately sent to the second recording amplifier 16, and the recording of the second field (Y ₂ ) is performed (steps S44, S46,
S48).

After the recording of the second field (Y ₂ ) is performed in this manner, the system controller 44 controls the position of the image sensor as described later (steps S50 and S52: FIG. 7A).
reference). Next, an instruction is given to the ID modulator 44 to change the two bits for recording mode discrimination in the user's area of the ID signal to "01" (see FIG. 8) (steps S38 and S40), and the contact a of the switching switch 12A. And e are connected (Step S
42). Thereafter, the third write amplifier 18 and the magnetic head 26
The third field is recorded via (step S4)
8).

Similarly, recording of the fourth field is performed. That is, ID
An instruction is given to the ID modulator 44 to change the two bits for recording mode discrimination in the user's area of the signal to "10" (see FIG. 8) (steps S54, S38, S40), and the switch 1 is switched.
The contacts a and f of 2A are connected (step S42). The fourth field is recorded using the recording amplifier 20 and the magnetic head 28 (steps S44, S46, S48).

When recording the third and fourth fields,
The magnetic head is moved by the head moving mechanism 29, and the first
And the magnetic heads 22 and 24 used for recording the second field
It is also possible to use

Here, the high definition recording mode will be described with reference to FIGS. 7 (A) and 7 (B).

The high-definition recording mode combines two frame screens in which the 525 scanning line pitch is shifted upward or downward by 1/2, for example, as compared with an NTSC television having 525 scanning lines. The vertical resolution is doubled. That is, as shown in FIG.
By shifting the scan line pitch by half up or down between the first frame consisting of the first and second fields and the second frame consisting of the third and fourth fields,
The vertical resolution is about 1000 lines.

FIG. 7 (A) is a diagram schematically showing an imaging device for performing such high-definition recording. Driving means shown in this figure
The reference numeral 92 (for example, a bimorph element) shifts the image pickup device 91 such as a CCD by 1/2 scanning pitch in accordance with a position control signal sent from the system controller 44.
This position control signal is transmitted at step S52 shown in FIG.
As described above, when recording is performed in the high-definition recording mode, the control signal output from the system controller 44 prior to the recording of the third and fourth fields (that is, when the recording of the second field is completed). It is.

FIG. 5C shows a recording pattern in the high-definition recording mode at the time of monochrome recording. As can be seen from the figure, the four tracks from the outside are the recording pattern according to the above description. Therefore, when the second monochrome high-definition image is continuously recorded, four tracks are formed on the inner side as shown in FIG.

 Next, the color recording mode will be described.

When the operator specifies the color recording mode via the operation unit 82, the system controller 44 cancels the mute of the color signal FM modulation circuits 60 and 72. Therefore, input terminals 54 and 66
The RY signal and the BY signal input to are supplied to the FM modulation circuits 60 and 72 after being clamped by the clamp circuits 56 and 68, respectively, and then subjected to predetermined emphasis by the emphasis circuits 58 and 70. .

The RY signal and the BY signal FM-modulated by the FM modulation circuits 60 and 72 are respectively supplied to band-pass filters (BPF) 62,
After the unnecessary band is cut by 74, it is frequency-multiplexed by the adder 64 to form a multiple color difference signal. FIG. 3B shows the frequency distribution of the FM modulated RY and BY signals in the multiple color difference signal formed as described above.

Then, the multiple color difference signal is supplied to a contact point b of the switching switch 12B.

Next, the color field recording mode will be described with reference to the flowcharts shown in FIGS. 2 (A) to 2 (C).

When the operator specifies the field recording mode using the operation unit 82 (steps S2 and S56), the system controller 44
An instruction is given to the ID modulator 46, and the ID carrier from the PLL circuit 76 is modulated so that a predetermined code (see FIG. 8) is set in the user's area of the ID signal. Multiplex with signal. That is, an instruction is given so that "1" is set for the color / monochrome determination code (1 bit) and "00" is set for the recording mode determination code (2 bits) (step S58).

Thereafter, the contacts a and c and the contacts b and d of the switching switches 12A and 12B are connected (step S60).

When the operator gives an instruction to start recording, the system controller 44 rotates the spindle motor 38 at a constant speed (step S6).
2, S64), and then send the recording gate signal to the recording amplifiers 14 and 16. Thus, the recording of the luminance signal and the recording of the multiple color difference signal are performed (steps S66 and S68).

As shown in FIG. 6A, the recording track pattern in the color field recording mode recorded on the magnetic disk 30 as described above is such that one luminance signal track and one color difference signal track are arranged adjacent to each other. It has become a shape.

When the color field recording of the second field is performed following the recording operation, a pair of a luminance signal track and a color difference signal track are similarly formed continuously on the inner peripheral side of the second track.

Next, the case of performing color frame recording will be described.

When the operator designates the color frame recording mode by the operation unit 82 (steps S2, S56, S70), the system controller 44 gives an instruction to the ID modulator 46, and the color / color data is transmitted to the user area of the ID signal. The ID carrier from the PLL circuit 76 is modulated so that the black-and-white discrimination code (“1” for color) and the recording mode discrimination code (“01” representing the outer track of the frame recording mode: see FIG. 8) are set. Then, it is multiplexed with the luminance signal modulated by FM in the adder 10. (Steps S72, S74, S76).

Thereafter, the switching switches 12A and 12B are controlled to connect the contacts a and c and the contacts b and e, respectively (step S78).

When the operator instructs the start of the recording operation from the operation unit 82, after the spindle motor 38 reaches the constant speed rotation (step S78,
S80), the system controller 44 similarly sends the recording gate signal to the first recording amplifier 14 and the third recording amplifier 18, and first simultaneously records the luminance signal of the first field and the multiplexed color difference signal of the first field (step S80). S84, S86).

When this recording is completed, the system controller 44
An instruction is given to the ID modulator 44 to change the recording mode discrimination code to "10" (inner track: see FIG. 8) in the user area of the ID signal (steps S88, S74, S7).
6). Thereafter, the switching switches 12A and 12B are controlled to connect the contacts a and d and the contacts b and f, respectively (step S78).

Then, the recording gate signal is immediately transmitted to the second recording amplifier 16.
Then, the luminance signal of the second field and the multi-color difference signal of the second field are simultaneously recorded (Steps S84 and S86).

FIG. 6B is a diagram showing a recording pattern formed on the magnetic disk 30 by such an operation. In the above-described color frame recording mode, simultaneous recording of Y ₁ and C ₁ (multiple color difference signals of the first field) tracks is performed.
Next, the reason why simultaneous recording of Y ₂ and C ₂ (multiple color difference signals of the second field) tracks were performed (that is, the reason why divided recording was performed every other track) was due to the influence of crosstalk between adjacent magnetic heads. In order to keep the minimum.

Further, when the color frame recording of the second frame is continuously performed, four tracks may be formed inside the four tracks already formed by the same control means.

Next, the first color high-definition recording mode will be described.

When the operator sets the first color high-definition recording mode using the operation unit 82 (steps S2, S56, S70, S90), the system controller 44 gives an instruction to the ID modulator 46, and the user enters the user area of the ID signal. “1” (color) as color / black and white discrimination code, “11” as recording mode discrimination code
(Outer track in first high-definition recording mode: No. 8
The ID carrier from the PLL circuit 76 is modulated so as to set (see the figure), and the adder 10 multiplexes with the luminance signal FM-modulated. (Steps S92, S94, S96).

Next, by controlling the switching switch 12A, the contacts a and c are controlled.
And (step S98).

When the operator gives an instruction to start the recording operation by the operation unit 82, after the spindle motor 38 reaches the constant speed rotation (steps S100 and S102), the system controller 44 sends the recording gate signal to the first recording amplifier 14. Then, the luminance signal of the first field (track Y ₁ : see FIG. 6 (c)) is recorded (step S104).

When the recording of the first field is completed, the recording mode discrimination code is changed to "10" (see FIG. 8).
An instruction is given to the D modulator 44 (steps S106, S94, S96). Next, the contacts a and d of the switching switch 12A are connected (step S98), and the recording gate signal is sent to the second recording amplifier 16 (steps S100, S102, S104). This records the luminance signal of the second field (track Y ₂ : see FIG. 6 (c)).
To end.

Next, the system controller 44 gives an instruction to the head moving mechanism 29 to move the magnetic head by two tracks toward the inner diameter side of the magnetic disk 30 (step S108), and to control the position of the image pickup device (see FIG. 7A). Is output (Step S1)
Ten). Thus, as described above with reference to FIG. 7B, the second frame signal obtained when the position of the image sensor 91 is shifted by half the pitch of the scanning line with respect to the first frame signal is actually recorded. Input to the device.

Then, the system controller 44 changes the recording mode discrimination code to “01” (see FIG. 8) so as to change it.
An instruction is given to the D modulator 44 (steps S112 and S114), and the contacts a and c and the contacts b and e of the switching switches 12A and 12B are connected respectively (step S116).

Thereafter, the system controller 44 sends the two recording gate signals to the first recording amplifier 14 and the third recording amplifier 18 (steps S118, S120, S122). Thus, the luminance signal of the first field in the second frame (track Y _3: Figure 6 (c) refer) and multiplexed chrominance signal (track
C ₃ ) Recording is performed simultaneously.

After the track Y ₃ and C ₃ are formed, the system controller 44 the code for discriminating the recording mode "10"
An instruction is given to the ID modulator 44 to change to (see FIG. 8) (steps S124, S112, S114), and the contacts a and d and the contacts b and f of the switching switches 12A and 12B are respectively connected (FIG. 8). Steps S114 and S116).

The system controller 44 sends the two recording gate signals to the second recording amplifier 16 and the fourth recording amplifier 20,
Luminance signal of the second field in the second frame: recording (track Y ₄ FIG. 6 (C) see) and multiplexed chrominance signal (track C ₄₎ is carried out at the same time (step S118, S120, S12
2, S124).

Thus, a recording track pattern shown in FIG. 6C is formed on the magnetic head 30 by the recording operation.

In the above description, the color difference signals C ₃ ,
It was recorded C _4, but it is also possible to record the color difference signals C _1, C ₂ of the first frame. Further, in the above embodiment, a multi-channel magnetic head of four channels is used. However, when a multi-magnetic head of eight channels is used, it is needless to say that the movement of the magnetic head becomes unnecessary.

Next, the second color high-definition recording mode will be described.

First, when the operator instructs the second high-definition recording mode of color using the operation unit 82 (steps S2, S6, S70, S90, S1).
26), the system controller 44 gives an instruction to the ID modulator 46, and “1” (color) for color / monochrome determination and “11” (second high definition) for the color / monochrome determination in the user's area of the ID signal. PL so that the outer frame and outer track in the recording mode are set (see FIG. 8).
The ID carrier from the L circuit 76 is modulated, and the F
Multiplex with the M-modulated luminance signal (steps S128, S130, S
132).

The recording means described below is based on the premise that an 8-channel multi-magnetic head is used.

First, "1" to the user's area of the ID signal, "11" as the (Figure 6 and see FIG. 8), the luminance signal of the first field in the first frame (track Y ₁₎ and multiplexed chrominance signal (track C ₁ Recording at the same time (step S1)
34, S136, S138, S140, S142).

Next, the recording mode discrimination code in the user's area of the ID signal is changed to "10" (see FIG. 5).
An instruction is given to the D modulator 44 to simultaneously record the luminance signal (track Y ₂ ) and the chrominance signal (track C ₂ ) of the second field in the first frame (steps S144, S148, S130, S
132, S134, S136, S138, S140, S142).

Further, the position of the image pickup device is controlled (see FIG. 7A), the recording mode discrimination code is changed to "01" (see FIG. 8), and the luminance signal of the first field in the second frame (see FIG. Track Y ₃ ) and multiple color difference signals (track
C ₃ ) are recorded simultaneously (steps S144, S146, S130, S132,
S134, S138, S140, S142).

Finally, the recording mode discrimination code is set to "10" (eighth
An instruction is given to the ID modulator 44 so as to change the luminance signal (track Y ₄ ) and the chrominance signal (track C ₄ ) of the second field in the second frame.

Thus, eight recording tracks are formed on the magnetic disk 30 as shown in FIG. 6 (D).

For the two bits of information in the field / frame area specified in the Still Video Format (EIAJ), the code shown in FIG. 7 described above is multiplexed with the luminance signal that has been FM-modulated during recording. This represents the recording mode determination code. That is, the feature of the code assignment shown in FIG. 7 is that the combination of two bits (1, 1) corresponding to the first and second high-definition recording modes is added in addition to the provisions of the still video format. Thus, the outer / inner track of the first frame and the outer / inner track of the second frame can be distinguished.

Next, as shown in FIGS. 5 (A) to 5 (C) and FIGS. 6 (A) to 6 (D), a procedure for reproducing an image signal from a recording track formed on a magnetic disk. Will be described.

FIG. 9 shows a block diagram of a reproduction system. In this figure,
100 is a magnetic disk, 102, 104, 106, 108 are magnetic heads, 11
0 is a head drive mechanism, 112 is a spindle motor, 114 is a spindle motor control circuit, 116 is a PG pulse generator, 118A,
118B is a switching switch, 128 is a band-pass filter (BPF) for passing a predetermined band of a reproduction ID signal, and 130 is an ID
A demodulator, 120 is a band-pass filter (BPF) for passing only a predetermined band of the reproduced FM luminance signal, 122 is an equalizer, 124 is an FM demodulation circuit, and 126 is a de-emphasis having an inverse characteristic to the emphasis characteristic at the time of recording. A circuit 126A is a luminance signal output terminal to which a composite synchronizing signal is added.
132 is a band-pass filter (BPF) for passing only a predetermined band of the reproduced FM R-Y signal, 134 is an equalizer, 136 is an FM demodulation circuit, 138 is a de-emphasis circuit, 13
8A is an RY signal output terminal. 140 is the regenerated FM B
A band-pass filter (BPF) that passes only a predetermined band of the -Y signal, 142 is an equalizer, 144 is an FM demodulation circuit, 146 is a de-emphasis circuit, and 146A is a BY signal output terminal. 150 is a system controller, 152 is a synchronization signal separation circuit, 154 is a vertical synchronization signal separation circuit, and 156 is a dropout detection circuit.

Hereinafter, the operation of the reproduction system will be described with reference to the flowcharts shown in FIGS. 10 (A) and 10 (B).

First, the magnetic disk 100 is rotated at a predetermined rotation speed (steps S200, S202).

Initially, the switching switch 118A keeps only the contacts a and e in a connected state (that is, reproduces the outermost track), and finds the track where the FM luminance signal including the synchronization signal is recorded (steps S203 and S206). At this time,
The track in which the FM luminance signal is recorded may be found based on the presence or absence of the carrier of the reproduction ID signal.

When a track on which the FM luminance signal is recorded is detected, the system controller 150 decodes the ID signal (step S208).

That is, in the reproduced FM luminance signal, only the reproduced ID signal from which unnecessary bands have been removed through the BPF 128 is supplied to the ID demodulator 130, where it is demodulated, converted into a identifiable signal form, and sent to the system controller 150. . Then, the system controller 150 decodes the content.

The system controller 150 automatically sets the playback mode according to the content of the ID that has been decrypted in this way.
Next, each playback mode will be described.

(1) When the recording mode discrimination code (see FIG. 8) is in the field recording mode "00" (1-1) When the color / monochrome discrimination code is in the black and white recording mode "0" (1-1-1) If the recording mode discrimination code is "00" (field recording mode) (steps S210 and S212),
Switch to the field playback mode.
Only the contacts a and e of 8A are kept connected, and the FM demodulation circuits 136 and 144 for the reproduced FM multiplexed color difference signal are muted. Therefore, B
The FM luminance signal from which the unnecessary band has been removed by the PF 120 is subjected to predetermined correction by the equalizer 122, and then the FM demodulation circuit 124
, And is further demodulated by the de-emphasis circuit 126.
, And is output from the output terminal 126A (step S214).

By repeating the above procedure, a monochrome image having the same field as that at the time of recording is reproduced (step S216).

(1-2) When the color / monochrome discrimination code is in the color recording mode "1" (1-1-2) If the recording mode discrimination code is "00" (field recording mode) (steps S210 and S242),
Contact points a and e and contact point b of the switching switches 118A and 118B
And F are PG output by the PG pulse generator 116, respectively.
The connection state is established in synchronization with the pulse, and further, the mu of the FM demodulation circuits 136 and 144 for the reproduced FM multiplexed color difference signal is released (steps S244 and S246).

As a result, the FM luminance signal (track Y ₁ ) for one field is reproduced in the same manner as in (1-1-1). On the other hand, after unnecessary bands are removed by the reproduced BPFs 132 and 140, the FM multiplexed color difference signals (track C ₁ ) for one field are respectively subjected to a predetermined correction in the equalizers 134 and 142 and demodulated by the FM demodulation circuits 136 and 144. Further, day-emphasis is performed by day-emphasis circuits 138 and 146.
Thus, the RY signal and the BY signal are output from the output terminal 13 respectively.
Output from 8A and 146A.

By repeating the above operation, a field color image signal of the same color as at the time of recording is reproduced and output (step S216).

(2) When the recording mode discrimination code is "01" (outer track of the frame recording mode: see FIG. 8) First, the magnetic head 102 corresponds to the outer track, and the magnetic head 104 corresponds to the inner track of the track. The head moving mechanism 110 controls the movement of the head so as to make contact with the head.

(2-1) When the color / monochrome discrimination code is "0" (black and white recording) (2-1-1) When the recording mode discrimination code is "01", the frame reproduction mode (step S218) is executed. Therefore, the contacts a and e and the contacts b and c of the switching switches 118A and 118B are alternately switched at a timing synchronized with the PG pulse generated by the PG pulse generator 116 (step
S220), FM luminance signals of the first and second field: Play (track Y _1, Y ₂ FIG. 5 (B) below) The (step
S222, S224).

By repeating this procedure, a black and white frame image signal is obtained (step S226).

(2-2) When the color / monochrome discrimination code is "1" (color recording) (2-2-1) When the recording mode discrimination code is "01", the frame reproduction mode (step S250) is executed. Therefore, the PG pulse generator 116 generates the operation of simultaneously connecting the contacts a and e and the contacts c and f of the switching switches 118A and 118B, and the operation of simultaneously connecting the contacts b and e and the contacts d and f of the switching switches 118A and 118B. Are alternately performed at a timing synchronized with the input PG pulse (step S252).
And the second field color signal is alternately reproduced (steps S254 and S256).

By repeating such an operation, a color frame image signal is reproduced (step S258).

(3) Recording mode discrimination code is "11" (high-definition recording)
(3-1) When the color / black and white discrimination code is "0" (black and white recording) (3-1-1) When the recording mode discrimination code is "11" (Step S228), the system controller 150 sets the magnetic head 10
2,104,106,108 are the corresponding codes "11", "10", "0"
The position of the magnetic head is controlled by the head moving mechanism 110 so as to abut against the track having 1 "and" 10 ".

Next, by controlling the switching switch 118A,
The PG pulse generator 116 causes the contacts a and e to be connected, the contacts b and e to be connected, the contacts c and e to be connected, and the contacts d and e to be connected. Repeat in synchronization with the timing of the generated PG pulse (step
S230).

Thus, Y ₁ Y ₂ Y ₃ Y ₄ Y ₁ Y ₂
Y ₃ Y ₄ ... high-definition black-and-white high-definition image signal as is repeatedly outputted (step S232, S234, S236, S238, S240).

(3-2) When the color / monochrome discrimination code is "1" (color recording) (3-2-1) When the recording mode discrimination code recorded on the outermost track is "11", the first Or second
This is the high definition playback mode.

Here, the description will be made on the assumption that reproduction is performed using an 8-channel multi-magnetic head (not shown).

That is, the recording track recorded in the first high-definition recording mode is composed of four FM luminance signal recording tracks and two FM multiplexed chrominance signal recording tracks, and the signals reproduced from these recording tracks are used. Since a single high-definition color image is formed (see FIG. 6 (C)), a track containing no ID signal (ie,
That is, there are two tracks on which FM multiplex color difference signals are recorded. Therefore, when reproduction is performed using an 8-channel multi-magnetic track, when the following conditions (a) to (c) are satisfied, it may be determined that recording in the first high-definition recording mode has been performed. Yes (step
S260).

(A) "11" is detected from the outermost track as a recording mode discrimination code.

(B) FM tracks are recorded on all four tracks including the outermost track.

(C) Of the signals reproduced from the magnetic heads of the eight channels, no ID signal is detected from two adjacent magnetic heads.

Similarly, when the following conditions (a) to (c) are satisfied, it can be determined that recording has been performed in the second high-definition recording mode (step S272).

(A) "11" is detected from the outermost track as a recording mode discrimination code.

(B) FM tracks are recorded on all four tracks including the outermost track.

(C) Of the signals reproduced from the magnetic heads of the eight channels, no ID signal is detected from the four adjacent magnetic heads.

(3-2-1-1) In the first high-definition reproduction mode (step S260), the FM luminance signal is synchronized with the PG pulse output from the PG pulse generator 116 as in the black-and-white reproduction mode. To control the switching switch to track Y ₁ Y ₂
Repeat playback of Y ₃ Y ₄ Y ₁ Y ₂ … (Steps S264, S266,
S268, S270).

At the same time, the FM multiplexed color difference signal
Repeat playback of C ₃ C ₄ C ₃ C ₄ …

Finally output terminals 126A, 138A, signal form appearing at 146A is, Y output _{... Y 1 Y 2 Y 3 Y} 4 Y 1 Y 2 Y 3 Y 4 ... R-Y output _{... R-Y 3 R-Y} 4 R −Y ₃ R−Y ₄ R−Y ₃ R−Y ₄ R−Y ₃ R−Y ₄ … BY output… B−Y ₃ B−Y ₄ B−Y ₃ B−Y ₄ B−Y ₃ B −Y ₄ B−Y ₃ B−Y ₄ …

(3-2-1-2) In the second high-definition reproduction mode (step S272), if the 8-channel multi-magnetic head is used as described above, the FM luminance signal is output from the PG pulse generator 116. By controlling the switching switch in synchronization with the PG pulse, the track Y ₁ Y ₂ Y ₃ Y ₄ Y ₁ Y ₂ Y ₃ Y ₄ ... (FIG. 6D)
(See steps S276, S278, S28)
0, S282).

On the other hand, with respect to the FM multiplex color difference signal, unlike the case of the first high-definition reproduction mode, the track C ₁ C ₂ C ₃ C ₄ C ₁ C ₂ C ₃ C ₄ . As a result, the color image recorded and reproduced in the second high-definition reproduction mode has higher color vertical resolution than the first high-definition reproduction mode.

The signal form finally appearing at the output terminals 126A, 138A, 146A is as follows.

Y Output _{... Y 1 Y 2 Y 3 Y} 4 Y 1 Y 2 Y 3 Y 4 ... R-Y output _{... R-Y 1 R-Y} 2 R-Y 3 R-Y 4 R-Y 1 R-Y 2 R −Y ₃ R−Y ₄ … B−Y output… B−Y ₁ B−Y ₂ B−Y ₃ B−Y ₄ B−Y ₁ B−Y ₂ B−Y ₃ B−Y ₄ … Processing of image signals reproduced in the first and second high-definition reproduction modes will be described.

FIG. 11 is a block diagram of a reproduction scan converter. The scan converter shown in the figure is a device that converts two frame images corresponding to the NTSC system into one high-definition television image and corrects a dropout generated during reproduction.

FIG. 12 is a flowchart showing the operation of FIG.

Next, the operation of the reproducing scan converter will be described with reference to FIG. 11 and FIG.

When it is determined that a track is formed according to the high-definition recording mode by determining the ID signal recorded on the magnetic disk (steps S300, S302, S304).
The reproduced luminance signal Y and chrominance signals RY and BY are converted into RGB signals by an RGB matrix circuit 208 via input terminals 201, 202 and 203, and thereafter are converted into 8-bit digital signals per sample by A / D converters 210, 212 and 214. The data is converted to data and sent to the switches 215, 216, 217. These switches 215,216,2
17 is connected to the A side in the figure under the control of the memory control circuit 234, and the first frame image data is also controlled by the memory control circuit 234 and connected to the C side in the figure. 218,219,220
Are stored in the first frame memories 222, 226, 230 via
Next, the switches 218, 219 and 220 are connected to the D side in the figure, and
The second frame memory 224,
It is stored in 228 and 232 (steps S308, S310, S312 and S314).

The memory control circuit 234 is supplied with a dropout detection pulse from the dropout detection circuit 156 shown in FIG. 9 via the input terminal 206, and the dropout detection circuit 156 shown in FIG. The amplitude level of the reproduced signal reproduced by the magnetic heads 102 to 108 and output from the switch 118A is monitored. If the amplitude level falls below a predetermined level, it is regarded that a dropout has occurred, and FIG. ) Are output to the memory control circuit 234.

The memory control circuit 234 is supplied with a composite synchronizing signal from the synchronizing signal separating circuit 152 shown in FIG. 9 via the input terminal 204 shown in FIG. 11, and the memory control circuit 234 detects the dropout. pulse,
Using the composite synchronization signal, the configuration shown in FIG.
The pulse signal shown in FIG.

FIG. 13 is a diagram showing a part of the configuration of the memory control circuit 234. In FIG. 13, 234a is a horizontal synchronizing signal separation circuit, 234b is an RS flip-flop (RSFF),
234c is a delay circuit (DL), 234d is a D flip-flop (D
FF), 234e is 524H (H is horizontal synchronization period) delay circuit (D
L), 234f is an AND gate, and 234g is an inverter.

The horizontal synchronizing signal as shown in FIG. 14 (b) is separated from the composite synchronizing signal supplied from the synchronizing signal separating circuit 152 in FIG. 9 by the horizontal synchronizing signal separating circuit 234a. Is supplied to the reset terminal (R in the figure) of the RSFF234b and the clock terminal of the DFFFF234d and DL234e, and the dropout detection pulse supplied from the dropout detection circuit 156 in FIG. FF23
It is supplied to the set terminal (S in the figure) of 4b and the inverter 234g.

As described above, when the composite synchronizing signal and the dropout detection pulse are supplied to the respective circuits, the respective circuits output signals shown in FIG. 14 (c).
Each signal is output at a timing as shown in FIGS.
A signal having a waveform shown in FIG. 14 (h) is output from the AND gate 234f, and B signals in the switches 215, 216 and 217 in FIG.
It is supplied to the terminal.

As described above, the switching operation of the switches 215, 216, and 217 in FIG. 11 is controlled by the memory control circuit 234, and the memory control circuit 234 includes the A / D converters 210 and 21.
During a period corresponding to the LSB (least significant bit) of each data serially output from 2,214, the switches 215, 216, 217 are connected to the B side in the figure, and during a horizontal scanning period in which a dropout occurs from the switches 215, 216, 217. Only during the period during which the dropout occurs, data is output in which the LSB is at the low level (ie, “0”) and the other periods are at the high level (ie, “1”). Further, the memory control circuit 234 stores data during the horizontal scanning period in which a dropout occurs when storing data in the frame memory, together with an error flag indicating that the dropout has occurred.

After the end of the storage operation, the memory control circuit 23
4 switches to the high-definition readout mode, and reads out the first frame image data (two non-interlaced field image data) stored in the first frame memory at a reading speed almost twice as fast as the above-mentioned storage. Then, the second frame image data (the field image data for the two frames) stored in the second frame memory is similarly read non-interlaced (steps S316 and S318).

At the time of reading image data, the memory control circuit 234 first determines which scan line of the data group corresponding to each scan line contains the data in which the dropout has occurred in the frame memory. It is determined by detecting whether the above error flag is set or not. As a result of the determination, when reading a data group corresponding to the scanning line where the data in which the dropout has occurred exists, the LSB of the data is set to “ 0 ", that is, for data in which a dropout has occurred, an average value of data corresponding to, for example, upper and lower scanning lines on a screen in a data group corresponding to a scanning line in which a dropout has not occurred. Is output, and if the LSB of the data is "1", that is, data for which no dropout has occurred, the data is output. Data LSB of the data group corresponding to the scan line where no dropout occurs.
For example, reading of image data from the frame memories 222, 224, 226, 228, 230, and 232 is controlled so that the data is replaced with data representing the average value of the LSB of the data corresponding to the upper and lower scanning lines on the screen.

By alternately repeating the non-interlaced reading of the first frame image data and the non-interlaced reading of the second frame image data as described above, high-definition interlaced image data of 1125 scanning lines is formed. .

The high-definition interlaced image data formed by the above operation is converted into analog signals by the D / A converters 236, 238 and 240, and sent to the conversion matrix circuit 242 (step S32).
0). The conversion matrix circuit 242 is a circuit for obtaining Y, C _W, a C _N signal for high definition television from RGB signals constituting a high-definition interlaced image signal. That is,
After passing through the conversion matrix circuit 242, high quality Y, C _W , C
_{The N} signal is output from the output terminals 244,246,248.

As described above, according to one embodiment of the present invention, image 1
When recording image signals corresponding to the number of sheets into a luminance signal and a chrominance signal separately, they are recorded together.For example, when performing only monochrome recording, only the recording track of the luminance signal is magnetic. Since it is formed on a disk, unused tracks are not generated, so that efficient recording can be performed according to each recording mode. In other words, when only monochrome recording is performed on one magnetic disk, track positions where luminance signals are recorded as odd-numbered tracks and chrominance signals are recorded as even-numbered tracks are fixedly determined. The number of images that can be recorded is increased as compared with the case where the pair is configured and recorded, and it becomes more economical.

Further, even in the case where only the color signal is erased from the magnetic disk on which the color image signal has already been recorded, in the present embodiment, the tracks on which the color signals of the color image signal are recorded are arranged adjacent to each other. Efficient erasing can be easily performed. Further, when re-recording data on a track after erasure, there is an advantage that recording is easy because a plurality of empty tracks are generated.

In one embodiment of the present invention, a recording mode discrimination code indicating whether a signal is recorded in the black-and-white recording mode or a signal recorded in the color recording mode is multiplexed and recorded on the luminance signal. The reproduction sequence of the color image signal, in which the recording track on which the color image signal is recorded is reproduced first, the recording mode discriminating code is used to determine whether the recording is performed in the black and white or color recording mode, and the color signal is reproduced. This can be performed, and the erroneous determination of the recording mode is less than in the case where the color / monochrome determination processing is performed based on the presence or absence of the burst signal.

In addition, since the luminance signal and the chrominance signal are recorded on separate recording tracks, a configuration such as a filter for separating the signals during reproduction is not required, and the signal is not deteriorated by the filter. Further, by reproducing only the track on which the luminance signal is recorded, at least a black and white image signal can be obtained.

In one embodiment of the present invention, there are 525 scanning lines, and each scanning line is composed of two frame images whose positional relationship is shifted up or down by 1/2 of the scanning line pitch. Since the first and second high-definition image signals can be recorded and reproduced, and the discrimination information of the first and second high-definition recording modes is multiplexed and recorded on the luminance signal, the recording mode at the time of reproduction is The discrimination can be performed easily and accurately, and further, by supplying the discrimination information to an external device such as a scan converter, there is no need to provide a discrimination circuit or the like on the external device side.

Further, as described above, in the embodiment of the present invention, the image signal reproduced at the time of reproducing the high-definition image is digitized, and the high-definition image is reconstructed on the memory by temporarily storing it in the memory. Further, by using the LSB of each sample data stored in the memory as a bit indicating whether or not a dropout has occurred, the dropout can be easily corrected on the memory, and the dropout can be compensated for. There is no need to add a new memory or increase the capacity.

In this embodiment, FM modulation RY, B for one field is used.
Although the -Y signal is frequency-multiplexed and recorded on one recording track, a better image can be recorded if the FM modulated RY and BY signals are separately recorded on the recording track. And can be played.

In the above-described embodiment, concentric tracks are formed on the magnetic disk by recording on the magnetic disk. Recording and reproduction are performed using an optical disk and a band-shaped magnetic recording medium (magnetic tape). Of course, the present invention can be applied to an apparatus.

[Effects of the Invention] As described above, the image signal reproducing apparatus according to the present invention can satisfactorily reproduce the luminance component signal from a recording medium on which the luminance component signal having a wide frequency band is recorded. In addition, the image signal can be reproduced from the recording medium without being affected by the distortion caused by the intermodulation of the luminance component signal and the color component signal, and the image signal can be reproduced without being affected by the dropout generated during the reproduction of the recording medium. It is possible to provide an image signal reproducing device configured to be able to restore a signal.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a recording apparatus to which the present invention is applied, FIGS. 2 (A) to 2 (C) are flowcharts showing the operation of FIG. 1, FIG. 3 (A) and FIG. 3 (B) is a diagram illustrating each signal band distribution, FIG. 4 is an explanatory diagram of a user's area in an ID signal multiplexed on a luminance signal, and FIGS. 5 (A) to 5 (C) are black and white. 6 (A) to 6 (D) are diagrams for explaining the track formation in the color recording mode, and FIGS. 7 (A) and 7 (B) are for high definition. FIG. 8 is an explanatory diagram of a recording mode discrimination code, FIG. 9 is a block diagram of a reproducing apparatus to which the present invention is applied, FIG. 10 (A) and FIG. 10 (B) are FIG. 9 is a flowchart showing the operation of FIG. 9. FIG. 11 is a scan converter used in the high-definition mode. FIG. 12 is a flowchart showing the operation of FIG. 11, FIG. 13 is a diagram showing a part of the configuration of the memory control circuit of FIG. 11, and FIG. 5 is a timing chart showing a signal waveform. 2 Luminance signal input terminal 4 Clamp circuit 6 Emphasis circuit 8 FM modulation circuit 10 Adder 12A, 12B Switching switch 14,16,18,20 Recording amplifier 22,24, 26, 28: Magnetic head part 29: Head moving mechanism 30: Magnetic recording medium (magnetic disk) 32: Center core 34: PG pin (magnet for detecting the rotational phase of magnetic disk 30) 36 ... ... PG coil 38 ... Spindle motor 40 ... Spindle motor control circuit 42 ... PG pulse generator 44 ... System controller 46 ... ID modulator 48 ... Sync separation circuit 50 ... Clamp pulse generator 52 ... Vertical Synchronization signal generation circuit 54 Input terminal for color difference signal RY 56 Clamp circuit 58 Emphasis circuit 60 FM modulation circuit 62 Band pass filter (BPF) 64 Adder 66 Color difference signal BY input terminal 68 …… Clamp circuit 70 Emphasis circuit 72 FM modulation circuit 74 Band-pass filter (BPF) 76 PLL circuit

Claims (1)

(57) [Claims] When recording an image signal for one screen having a luminance component signal and a color component signal, said luminance component signal,
An apparatus for reproducing an image signal from a recording medium recorded in a state where at least one of the color component signals is divided into a plurality of areas, wherein a luminance component signal recorded on the recording medium is provided. And a color component signal, and reproduces each signal in a predetermined unit, and detects whether a dropout has occurred in a signal output in a predetermined unit from the reproduction means. Drop-out detection means, and determining whether the drop-out has occurred in a part of the luminance component signal and the color component signal output for each predetermined unit from the reproduction means according to the detection result of the drop-out detection means. Storage means for converting the luminance component signal and the color component signal into separate storage areas, respectively; and a luminance component signal and a color component signal stored in the storage means. When reconstructing an original image signal for one screen, the index signal indicates that a dropout has occurred. An image signal reproducing device comprising a control unit.