JPH0358371A - Code signal recording system - Google Patents

Abstract

PURPOSE:To record and regenerate a code signal irrespective of tracking of a rotary head or a hit of the head by turning the code signal into a low frequency signal and recording it is coinciding waveforms with each other between adjacent tracks. CONSTITUTION:The code signal is turned into the low frequency signal corresponding to a horizontal period of a diagonal track in phase, and moreover the code signal is shifted in accordance with an offset with an adjacent track of the diagonal track. Then, by recording this code signal in superimposing it upon an information signal, the waveforms of the code signal to be recorded between the adjacent tracks coincide with each other. Thus, by turning the code signal into the low frequency signal, influence of a spacing loss etc., is alleviated. In addition, by coinciding the waveforms between the adjacent tracks with each other, the code signal can be regenerated irrespective of the tracking and hit of the head.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a code signal recording method applied to a rotary head type recording/reproducing device.

[Summary of the invention]

The present invention relates to a code signal recording method, in which the code signal is a low frequency signal and is shifted and recorded in accordance with the offset between adjacent tracks, thereby making the waveforms of the code signals recorded between adjacent tracks consistent. , code signals can be easily detected during variable speed playback.

[Conventional technology]

Conventional methods for recording code signals such as time codes in so-called helical scan VTRs and other rotary head type recording and reproducing devices include: (1) modulation of code signals on so-called longitudinal tracks that are separate from the diagonal tracks by the rotary head; Method of recording signals ■ A method has been implemented in which a code signal modulated in the same band as the information signal is inserted and recorded in a part of the diagonal track in a time-division manner.

[Problem to be solved by the invention]

However, in method (2) above, it is necessary to provide a fixed head separate from the rotary head for recording and reproducing the code signal, and in order to provide an area for the longitudinal track on the recording medium, the circuit structure must be changed. This results in problems such as increased complexity and decreased utilization of the recording medium for information signals.

On the other hand, method (■) solves the problem of method (■), but when the tracking of the rotating head deviates, the code signal cannot be played back, and especially in fast forward and rewind modes, the code signal cannot be played back due to the trajectory of the head search. There may be cases where this is not possible. Furthermore, since the information signal band is sensitive to spacing loss, there are problems such as the need for new means to maintain good head contact, especially in fast forward and rewind modes.

This application was filed in view of these points.

[Means to solve the problem]

In the present invention, when an information signal is recorded and reproduced on a diagonal track using a rotating head, and an arbitrary code signal is recorded and reproduced by superimposing the information signal on the information signal, the code signal is made into a low frequency signal and its phase is set as above. The waveform of the code signal recorded between the adjacent tracks is made to correspond to the longitudinal position (H address) of the diagonal track, and by shifting the code signal according to the offset between the adjacent tracks of the diagonal track. This is a code signal recording method in which the signals are matched.

[Effect]

According to this, the code signal is made into a low frequency signal, and the recording is performed so that the waveforms match between adjacent tracks, thereby solving the problem of tracking of the rotating head and head contact, and the problem of the code signal. Recording and playback can always be performed satisfactorily.

〔Example〕

That is, in the code signal recording method of this application, the code signal is a low frequency signal whose phase corresponds to the longitudinal position of the diagonal track, and the code signal is shifted in accordance with the offset between adjacent tracks of the diagonal track.

As a result, the recording pattern of the code signal on the recording medium is such that the waveforms of the code signals recorded between adjacent tracks are matched, as shown in FIG. 1, for example.

Therefore, according to this recording method, since the code signal is a low frequency signal, the influence of spacing loss etc. is reduced, and the problem of head permeability is solved. In addition, by matching the waveforms between adjacent tracks, code signals can be played back regardless of tracking, allowing normal playback,
Reproduction in fast-forward and rewind modes can always be performed satisfactorily, and code signals can also be reproduced even when the recording medium is stopped. Furthermore, there is no need to provide a separate track or separate bottom.

Furthermore, FIG. 2 shows an example of an apparatus for realizing the code signal recording method of this application. Note that this example is based on V. Regarding the recording and playback of time code signals such as TR, as will be described later in VTR, when the offset between tracks of an odd-even field that constitutes one frame is set to "0" and the offset between frames is set to one horizontal period. It was applied to

In this figure, first, at the time of recording, for example, a reference synchronous disk (not shown) for forming a recording signal or a horizontal synchronization signal (Rec Ref Hsync) for reference to a given recording is supplied to the input terminal (1). Similarly, a recording reference frame pulse (Rec Ref FP) from the synchronous disk is supplied to the manual terminal (2), and a preset value (for example, "5"") is supplied to the manual terminal (3).Then, the signals from these terminals (1) to (3) are supplied to the count terminal, preset terminal and preset terminal of the first H address counter (11), respectively. The signals from terminals (1) to (3) are supplied to the count terminal of the second H address counter (13) through the recording side contact of the recording/reproduction changeover switch (12), respectively. It is supplied to the preset terminal and the input terminal of preset 1st shift.

As a result, signals as shown in FIG. 3A to C are supplied to the counters (11) and (13) during recording, and an H address as shown in FIG. 3D is generated. Also, in the diagram? The addresses marked with are generated based on the previous frame pulse, but are generated accurately in normal operation.

The H addresses generated by these counters (11) and (13) are used as R O M (14) and (1) for decoding, respectively.
5). Then, the H address is ``0'' from the ROM<14) to which the H address of the counter (11) is supplied.
A signal corresponding to the period " is output. This signal is supplied to an AND circuit (16), and a signal that becomes "1" during recording is supplied to this AND circuit (16) through a terminal (17). The output signal of the AND circuit (16) is supplied to the count terminal of the frame counter (18), and the carry output when the first count of this counter (18) is "29" is supplied to the count terminal of the second counter (19). be done.

Therefore, during recording, the time code of the currently recorded track is stored in the counters (18) and (19).

Note that this time code is the number of seconds starting from the reset time such as the start of recording, and the frame number within that one second. The count values of these counters (18) and (19) are then supplied to the display device (20), where the frame number is displayed as is and the number of seconds is converted into hour, minute, and second values and displayed. .

Further, the count values of the counters (1g) (19) are respectively supplied to the subtraction circuit (21> (22).On the other hand, the R O to which the H address of the counter (13) mentioned above is supplied
From M (15), the H address is divided into 30 arbitrary addresses, and "
A frame offset value that repeatedly changes from "00" to "29" and a second offset value that changes from "-8" to "0" for each of the above divisions in each field (l/2 frame) are output. .These offsets are supplied to subtraction circuits (21) and (22), respectively.Furthermore, when the calculated value becomes "24" in the subtraction circuit (21), a carry signal is supplied to the subtraction circuit (22). supplied to human power.

This allows the time code to be set to 3 hours 5 when recording, for example.
At the end of the odd-numbered track of 9 minutes, 59 seconds, and 29 frames, the counters (18) and (19) contain the frame number "29" and the number of seconds in the above-mentioned hours, minutes, and seconds as hexadecimal values, as shown in FIG. 4AB. It is shaped like "383F". Furthermore, the counter (13) has an H address as shown in C in the same figure, and this H address is supplied to the R O
A frame offset value and a second offset value as shown in D and E of the figure are taken out from M (15). Therefore, by supplying these values to the subtraction circuits (21) and (22), the values shown in FIG. In synchronization with the carry signal, a value as shown in G in the figure is taken out.

When the value from this subtraction circuit (22) is binarized, it becomes as shown in H in the figure, and this binary value is sent to the selector (23).
D18~D15, D13~DIO, 'DO8~DO
5, DO3~DOO data is supplied to human power,
As shown in Figure I, terminals (
24〉, the value of “1” is supplied, and the data input D2
9. D19. D14, DO9, DO4
is supplied with an inverted value of "1". Furthermore, the signal from the subtraction circuit (21) is supplied to the select terminal of the selector (23).

Therefore, the values of each data D29 to DOO are taken out from the selector (23) as shown in J in the same figure, and this value is M
The signal is supplied to an FM encoder (25) and converted into a modulated signal as shown in ffiK, and this signal is supplied to a low-pass filter (26) to be converted into a signal as shown in figure L. This signal is taken out through the output terminal [4] and superimposed on the recording signal (not shown).

Furthermore, Figures 5 and 6 show cases where the time code is 4 hours 00 minutes 00 seconds 00 frame and 4 hours 00 minutes 00 seconds 01 frame, respectively, and the time code modulation signal is shaped in the same way as described above. . As is clear from these figures, in the output time code modulation signal, the second value of each time code is sequentially changed every 30 address sections by the second offset value, and the boundary position of this section is the frame number. It has been sequentially shifted by .

Therefore, by superimposing this signal on the recording signal and recording it by the rotary head, the recording waveform can be made consistent between adjacent tracks as described above. In addition, since the time code signal recorded in this case is an MFM signal in which 1 bit of the binary value corresponds to 1 horizontal period, the frequency of the time code signal is, for example, as long as the recording signal is NT
In the case of the SC method, the maximum is a low frequency signal of about 31.5 kHz.

In this way, recording is performed using the above-described recording method.

Furthermore, during playback, the horizontal synchronization signal (PaPLL }lsync in the playback signal stabilized by the PLL
) is supplied to the input terminal (5), and the signal from this terminal (5) is supplied to the count terminal of the counter (13) through the reproduction side contact of the changeover switch (12).

In addition, a pulse signal (drum P
G) is supplied to the manual terminal (6), and a preset value (for example "17") for specifying the timing of this pulse signal to an arbitrary horizontal period (H address) is supplied to the manual terminal (7).
frame pulse (PB) in the reproduced signal.
FP) is supplied to the manual terminal (8), and a preset value (for example, "9°") for specifying the timing of this reproduction frame pulse to an arbitrary horizontal period (H address) is supplied.
is supplied to the input terminal (9). Furthermore, these terminals (
6) The signals from (7) and (8) and (9) are respectively supplied to the changeover switch (27). At the same time, the terminal (
The regenerated frame pulse from 8) is fed to the monostable multi-by break (28), which
The selector switch (27) is set to the terminal (8) by the signal from the terminal (8) during a period that includes the timing of the reproduction frame pulse and covers the subsequent timing of the drum PG mentioned above.
9) side. And this changeover switch (27)
The signals are supplied to the preset terminal and preset value input terminal of the counter (13) through the reproduction side contact of the switching switch (12), respectively.

As a result, the human power terminals (5) to (9) are connected to the 7th terminal during playback.
If a signal as shown in FIG. is switched and the counter (13
) are supplied with signals as shown in G and H in the same figure, and I
An H address as shown in is generated. If a reproduction frame pulse is not obtained, signals as shown in FIG. 8G and H are supplied to the counter (13), and an H address as shown in FIG. 8I is generated. Also, in the diagram? The address appended with is the previous playback frame pulse or drum P.
It was generated based on C.

On the other hand, the reproduced signal is supplied to the input terminal (10). The signal from this terminal (10>) is supplied to a low-pass filter (29) and a certain portion of the time code modulation signal is extracted.

This extracted signal is supplied to the MFM decoder (30), and the time code in the reproduced signal is decoded by this decoder (30) by zero-cross detection etc. Furthermore, this decoded signal is sent to the shift register (31). DOO to DO3 of this shift register (31)
, DO5~DO8, DIO~D13D15~D
The signal obtained at the data output of 18 is supplied to an adder circuit (32). Further, the second offset value from the ROM (16) mentioned above is supplied to the adding circuit (32), and this added value is supplied to the manual input terminal of the preset value of the counter (19). The frame offset value from the ROM (16) is also supplied to the preset value input terminal of the counter (18). At this time, the ROM (15) is supplied with the H address formed in the above-mentioned reproduction counter (13).

Along with this, D20 to D28 of the shift register (31),
The signals obtained from the data outputs of D50 to D58 are supplied to the AND circuit (33), and the signals obtained from the data outputs of DO4, DO9,
D14, D19, D29. D34, D
39. The signals obtained at the data outputs of D44, D49, and D59 are inverted and supplied to an AND circuit (33), and this AND output is supplied to an AND circuit (34). Further, a signal which becomes "1" during reproduction is supplied to this AND circuit (34) through a terminal (35).

Furthermore, the above-mentioned DOO~DO3, DO5~DO8.
DIO~D13. The signals obtained at the data outputs of D15 to D18 and the signals obtained at the data outputs of D30 to D33. D35-D38
, D40 to D43, and the signals obtained from the data outputs of D45 to D48 are supplied to a subtraction circuit (36), and this subtracted value is supplied to a comparison circuit (37) and a terminal (38).
When they match, the comparison output is supplied to the AND circuit (34). Further, a detection enable signal corresponding to the latter half of each reproduced track is output from the ROM (14), and this signal is supplied to the AND circuit (34). This AND output is then supplied to the preset terminals of counters (18) and (19). Note that during playback, the VTR is driven in accordance with the reference signal from the above-mentioned synchronous disc.

As a result, during playback, for example, at the beginning of an odd track with a timing code of 3 hours 59 minutes 59 seconds 29 frames, the counter (13) outputs an H address as shown in FIG. 9A, and the ROM ( 15) from the same figure B
, C are output. Further, the ROM (14) outputs a detection enable signal as shown in FIG.

In contrast, the low-pass filter (29) outputs a signal as shown in Figure E, the zero cross of this signal is extracted as shown in Figure F, and the decoder (30> outputs the signal as shown in Figure G). A decoded signal is output. By supplying this decoded signal to the shift register (31), the H address of the counter <15> changes as shown in FIG. The AND circuit (33) receives an AND output of "1" as shown in the figure.At this time, the adder circuit (32) receives "384 bits" as shown in J of the same figure. and "3840" values are supplied.

Further, the subtraction circuit <36> is supplied with these values and the previous value as shown in K in the figure, and when the difference between them is "1" as shown in L in the figure, the comparison circuit (37) From○
A signal with K=“l” is taken out. Therefore, at this time, during playback, the detection enable signal of R O M (14) is “1”.
'', the output of the AND circuit (33) is "1" and the output of the comparison circuit (32) is ○K, so that the AND circuit (34) outputs the count (18) (
19) is output.

At this time, the counter (l8
) is as shown in N in the same figure, and the preset value supplied from the subtraction circuit (32) to the counter (19) is as shown in O in the same figure. By being preset, the counter (18) outputs a value of "29" as shown in P in the same figure, and the counter (19) outputs a value of "3" as shown in Q in the same figure.
A value of 83F" is output. This value is further converted into hours, minutes, and seconds, and the display device (20) displays 3 hours, 59 minutes, 59 seconds, and 29 frames as shown in R in the same figure. .

Furthermore, in Figures 10 and 11, the time code is 4.
Time 00 minutes 00 seconds 00 frames and 4 hours 00 minutes 00 seconds 0
In the case of one frame, the time code is reproduced and displayed in the same manner as described above. As is clear from these figures, the time code to be reproduced is shifted sequentially, and an accurate time code can always be obtained in association with the offset 1 shift formed from the H address.

In addition, in the above-mentioned apparatus, when recording continues from the middle of a tape that has already been recorded, the already recorded part is played back and its time code is displayed on the counter (18) (19).
) and then continue recording to record continuous time codes.

In this way, according to the above-mentioned apparatus, when an information signal is recorded and reproduced on a diagonal track using a rotary head, and an arbitrary code signal is superimposed on the information signal and recorded and reproduced,
By making the code signal a low frequency signal and making its phase correspond to the longitudinal position of the diagonal track, and by shifting the code signal according to the offset between the adjacent tracks of the diagonal track, the code signal can be shifted between the adjacent tracks. It is possible to implement a code signal recording method in which the waveforms of the code signals recorded are matched.

According to the method, the code signal is made into a low frequency signal, and the recording is performed so that the waveforms match between adjacent tracks, thereby solving the problem of tracking of the rotating head and head contact, and the code signal It is possible to always perform recording and reproduction of data well.

Note that this method is not limited to recording time codes, but can also be applied to recording chapter numbers, recording modes, titles, time axis reference pilots, and the like.

Furthermore, this method is applicable not only to VTRs but also to rotary head type recording and reproducing devices such as DATs and data recorders.

Furthermore, in the device of the above-mentioned specific example, each offset value etc. is determined according to the applied VTR etc., and an arbitrary value is written in the ROM etc. according to the applied VTR etc. It is.

〔Effect of the invention〕

According to the present invention, the code signal is made into a low frequency signal, and the recording is performed so that the waveforms match between adjacent tracks, thereby solving the problems of tracking of the rotating head and head contact, and the code signal It is now possible to always perform recording and playback in good condition.

[BRIEF DESCRIPTION OF THE DRAWINGS] Figure I is an explanatory diagram of an example of the present invention, Figure 2 is a diagram showing the structure of an example of a device for realizing the invention, and Figures 3 to 11 (explanatory diagrams for explaining the invention). (1) to (10) are terminals, (11) (13) (18
) (19) is a counter, (14) (15) is a ROM
, (20) are display devices, (21) and (22) are calculation circuits, (23) are selectors, (31) i-manft registers, and (32) are adder circuits. Agent Hidemori Matsukuma

Claims (1)

[Claims] When an information signal is recorded and reproduced on a diagonal track using a rotating head, and an arbitrary code signal is recorded and reproduced by superimposing it on the information signal, the code signal is made into a low frequency signal and its phase is by making it correspond to the longitudinal position of the diagonal track and shifting the code signal according to the offset between adjacent tracks of the diagonal track, so that the waveforms of the code signals recorded between the adjacent tracks match. A code signal recording method that allows