JP3445395B2 - Magnetic recording device and magnetic reproducing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital magnetic recording / reproducing apparatus having a rotary drum head.

[0002]

2. Description of the Related Art In recent years, digital processing of images has been studied. Magnetic recording / reproducing apparatus for digital image data (V
Various methods are also being considered for recording to (CR).
Generally, when a video signal is digitized, the amount of information becomes enormous, and it is difficult to transmit or record the information without compressing it in terms of communication speed and cost.

Therefore, an image compression technique is indispensable for transmitting or recording a digital video signal, and various standardization plans have been studied in recent years. MPEG for moving images
(Moving Picture Experts Group) method is standardized. In MPEG, DCT (Discrete Cosine)
Transform) Transform, interframe predictive coding, run length coding, and entropy coding are used in combination to code a video signal. That is, in the MPEG system, 1
Not only is compression by DCT (intraframe compression) performed within a frame, but interframe compression that reduces the redundancy in the time axis direction by utilizing the correlation between frames is adopted. The inter-frame compression is to further reduce the bit rate by taking advantage of the fact that a general moving image is very similar to the preceding and following frames and obtaining the difference between the preceding and following frames and encoding the difference value. In particular, motion-compensated interframe predictive coding that reduces prediction error by predicting motion compensation of an image and obtaining a difference between frames is effective.

A helical scan type VCR reads information recorded on a magnetic tape by tracing a recording track formed on the magnetic tape with a rotary drum head. The rotary drum head used in the VCR is, for example, 1 channel ×
There are two heads (hereinafter referred to as 1ch × 2). This 1c
In the h × 2 rotary drum head, a pair of heads having different azimuths are arranged at intervals of 180 ° on the circumference of the rotary cylinder.

Information is recorded on a magnetic tape using such a rotary drum head. In this case, on the magnetic tape, recording tracks A1, B1, A2, B2, recorded by the 1-ch × 2 rotary drum head as described above,
... to form. .. are recording tracks by the plus azimuth head, and B1, B2, .. are recording tracks by the minus azimuth head. Normally, at the time of reproduction, the recording tracks A1, A2, ... Are traced by a plus azimuth head, and the recording tracks B1,
B2, ... Playback is performed by tracing with a minus azimuth head. At the time of this normal reproduction, since the head trace coincides with the recording track, no particular problem occurs.

When performing high speed reproduction, the head traces while crossing the recording track. That is, at the time of high speed reproduction, only the portion where the azimuths of the heads and the recording track match each other is reproduced. Even in this case, it is 1 in analog recording in which the position on the screen corresponds to the recording position on the recording medium.
It is possible to reproduce the screen.

However, the code amount differs between the intra-frame compressed frame and the inter-frame compressed frame, and when the image data compressed by the MPEG system is recorded on the recording medium,
The vertical position on the screen of the image data does not correspond to the vertical recording position on the recording medium.
It is not always possible to reproduce one frame. Further, even with the data of the intra-frame compressed frame, the image signal cannot be decoded with arbitrary intermittent data, that is, high-speed reproduction cannot be performed like the analog signal.

Therefore, in Japanese Patent Application No. 6-065298 filed by the applicant of the present application, a method for intermittently recording data for high speed reproduction at the position of each track through which the head passes during high speed reproduction. Is proposed. At the time of reproduction, a high-speed reproduction image is obtained by accurately tracing the area in which the data for high-speed reproduction is recorded.

For example, when quadruple speed reproduction is possible, important data is recorded in an area where a sufficient envelope can be obtained during quadruple speed reproduction, for example, a high speed reproduction data area. That is, when the 1ch × 2 trace is adopted, the data is recorded in the area where the tracing is performed during the quadruple speed reproduction in the high speed reproduction data area.

By the way, in this proposal, the frequencies are f0, f1, f as the pilot signals for tracking.
2 types of signals (hereinafter, pilot signals f0, f1,
f2), and a pilot signal f1 for each track
, F0, f2, f0, f1, f0, f2, f0, ... For example, the pilot signal f0 is recorded on the tracks A1, A2, ... Of plus azimuth, and the pilot signals f1, f2, ... Are recorded on the tracks B1, B2, ... Of minus azimuth. The pilot signal f
As 0, a signal of a predetermined frequency may be set, or the pilot signal f0 may be a non-signal. Also,
In Japanese Patent Application No. 6-065298, the pilot signal f0 is recorded on the minus azimuth track, and the pilot signals f1 and f2 are recorded on the plus azimuth track.

At the time of reproduction, the levels of the pilot signals f1 and f2 included in the reproduced signal are compared, and control is performed so that the comparison levels match, that is, the track phase is aligned with the track on which the pilot signal f0 is superimposed. .
In this case, considering the track phase shift direction,
The track phase can be matched with the track of the pilot signal f0 every four tracks. That is, track A1
Alternatively, the track phase can be matched with the track A3. In this case, according to the above-mentioned proposal, tracks A1 A3
The same data is recorded in the high-speed reproduction data area, and similarly, the same data is recorded in the high-speed reproduction data area of tracks A1 A3. In other words, in the case of 4 × speed reproduction, 4
The same data is recorded for each track, and double speed number x 2
= Different data is recorded for every 8 tracks.

However, in the VCR, the track pattern may be bent due to variations in mechanical accuracy and adjustment error of the tape running system. This bend is different for each VCR, and when reproducing a magnetic tape recorded by another VCR, the head may not be able to reliably trace the recording track. That is, there is a problem such as compatibility. For example, when reproduction is performed by the same VCR as during recording, the trace pattern during reproduction also bends, and the recording track can be traced reliably. On the other hand, when reproducing a magnetic tape recorded by another VCR, the trace locus of the head is irrelevant to the curve of the recording track, and becomes linear, for example. Therefore, in this case, the head may not be able to accurately trace the recording track, and the high-speed reproduction data area may not be traced, and the high-speed reproduction data may not be reproduced. Therefore, in the specification of Japanese Patent Application No. 6-244278 previously filed by the applicant of the present application, it is possible to reliably trace the data area for high-speed reproduction even when the trace traces of the head differ during recording and reproduction. There has been a proposal to reproduce an image for high speed reproduction. In this proposal, the magnetic tape is driven by a tape drive device (capstan) to run. The reproduced signal is given to the amplifier, and on-track is achieved by the tracking circuit. During high speed reproduction, the data selector determines whether or not the high speed reproduction data area of the magnetic tape has been normally reproduced. When the reproduction is not normally performed, that is, when the trace trace of the head is different between the time of recording and the time of reproduction, the tracking circuit specifies n + 0.5 (n is an integer) double speed reproduction that does not exceed the multiple speed / 4. To do. This makes it possible to reproduce data corresponding to the entire area of, for example, the first track of four tracks (also referred to as a repeating unit), so that even if the reproduction trace pattern is different from that at the time of recording, the high-speed reproduction data area is surely secured. Can be played.

However, in the above-mentioned proposal, if the double speed number at the time of high speed reproduction is set to 24 times speed, when the high speed reproduction data area is normally reproduced, the 24 times speed reproduction is possible, but the normal reproduction is performed. If not, the speed is not exceeded by the tracking circuit as described above. N +
Even if the data area for high speed reproduction is surely reproduced by designating 0.5 (n is an integer) double speed reproduction, it does not exceed 6 (n +
0.5) (n is an integer), which is a 5.5 × speed reproduction. That is, about 1 high-speed playback is possible.
It becomes / 4, which is a problem of poor efficiency.

Further, in order to perform the backward high speed reproduction, a backward high speed reproduction data area is provided similarly to the forward high speed reproduction data area, and the same data as the forward data is reproduced in the backward high speed reproduction. Record in the data area for use.
During reverse high-speed reproduction, the rotational speed of the rotary drum head is not changed, and only the traveling direction of the magnetic tape is reversed and traced to reproduce the reverse reproduction data area and obtain reverse data. . However, in order to normally obtain a reverse high-speed reproduced image, it is necessary to always temporarily store and rearrange the reproduced data in a fixed unit in a buffer memory or the like, and carry out the same data output order as in the forward direction reproduction. there were.

[0015]

As described above, in the conventional magnetic recording / reproducing apparatus, high-speed reproduction is performed when reproducing a magnetic tape recorded by another VCR and when using a device having a different trace locus for reproduction. It is possible to reproduce the high-speed playback image by surely tracing the data area for
There is a problem that the double speed number becomes about 1/4 and the efficiency is not good.

Further, in the case of performing the backward high speed reproduction, the reproduced data obtained by tracing from the backward high speed reproduction data area is once stored in the buffer memory or the like, and the same output order as in the forward reproduction is used. There is also a problem that the data must be read so that the data is rearranged in a fixed unit.

Therefore, the present invention has been made in view of the above problems, and even when the trace locus of the head is different during recording and during reproduction, it is possible to improve the double speed number during high speed reproduction in the forward direction. (EN) Provided are a magnetic recording device and a magnetic reproducing device that do not require rearrangement of reproduction data when the high-speed reproduction speed is increased more than before and the high-speed reproduction area can be accurately reproduced during backward high-speed reproduction. To aim.

[0018]

A magnetic recording apparatus according to claim 1 of the present invention reproduces a tracking adjustment of a head when a track is formed on the magnetic tape by the head.
At the same time as multiplexing the pilot signal for the occasional use, the normal re- execution of the head of each track is performed for each of the predetermined number of tracks.
In a magnetic recording device for forming a high-speed reproduction data area at a plurality of predetermined positions in the trace direction at the time of live , the high-speed reproduction data in the forward direction of the first double speed number and the reverse direction of the second double speed number Data for high-speed reproduction are provided, and a plurality of high-speed reproduction data areas of each track are recorded in the head during normal reproduction of the head.
Alternately set to the forward direction area or the reverse direction area in the race direction, and the first double speed number is set in the forward direction area of a plurality of tracks traced by the head during the forward high speed reproduction of the first double speed number. forward sequentially records the high-speed reproduction data of the second multiple speed of fast reverse the in the reverse regions of the plurality of tracks by the head trace during playback second multiple speed reverse The magnetic reproducing device according to claim 5 of the present invention is recorded by the magnetic recording device according to any one of claims 1 to 4. Reproducing a magnetic tape, wherein the magnetic tape is run at a speed (n + 0.5) times (n is an integer) not exceeding (double speed / 2-1), and the forward direction recorded on the magnetic tape or Fast reverse playback Reproducing means for reproducing the data, characterized by comprising a permutation means for outputting rearrange the output from the reproducing means in chronological order.

According to another aspect of the magnetic recording apparatus of the present invention, a pilot signal for matching the tracking phase is multiplexed at a predetermined track interval, and a plurality of high-speed reproduction data areas are formed at a plurality of predetermined positions of the track. According to the present invention, a recording means is provided for recording the high-speed reproduction data of a predetermined double speed number in the high-speed reproduction data area repeatedly at a 2-track interval for a predetermined number of repetitions.

According to a tenth aspect of the present invention, there is provided a magnetic reproducing apparatus for reproducing a magnetic tape recorded by the magnetic recording apparatus according to any one of the first to ninth aspects. Playback in which the magnetic tape is run at a double speed (n + 0.5) (n + 0.5) which does not exceed the double speed number / 2-1) and the forward or backward high speed reproduction data recorded on the magnetic tape is reproduced. And means for rearranging the outputs from the reproducing means in the order of recording and outputting the rearranged means.

[0021]

According to the first aspect of the present invention, the recording means multiplexes pilot signals for matching tracking phases at predetermined track intervals of tracks formed on the magnetic tape, and at the same time, a predetermined track for each predetermined track. Recording is performed so as to form a plurality of high-speed reproduction data areas at a plurality of positions. In this case, the recording means is supplied with a predetermined high speed reproduction data of a high speed in the forward direction and a predetermined high speed reproduction data of a high speed in the reverse direction.
At this time, the recording means sets every other plurality of positions of the plurality of high speed reproduction data areas as a forward direction area, and sets the plurality of high speed reproduction data areas between the forward direction areas to each other. In the reverse direction area, the same data of the forward direction high speed reproduction data of a predetermined double speed number is repeatedly recorded at the predetermined track interval by a predetermined number of repetitions, and at the same time, in the reverse direction area, a predetermined double speed number is set. The same number of high-speed reproduction data in the opposite direction are repeatedly recorded at the predetermined track interval and a predetermined number of repetitions. This allows
It is possible to obtain normal high-speed reproduction data without rearranging the reproduction data during high-speed reproduction in the forward direction or the reverse direction.

[0022]

[0023]

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

FIG. 1 is a block diagram showing an embodiment of a magnetic recording apparatus and a magnetic reproducing apparatus according to the present invention.

In FIG. 1, an input terminal 1 receives a compressed signal of the MPEG2 system to be recorded. The compressed signal is given to the memory 2 and the special reproduction data generation circuit 4. The memory 2 stores the applied compressed signal, and at the time of reading, read control is performed based on the control signal from the output control circuit 6, and the memory 2 outputs the read compressed signal. Then, the read compressed signal is given to the terminal a of the changeover switch 3. The special reproduction data generation circuit 4 generates special reproduction data, that is, high-speed reproduction data necessary for performing high-speed reproduction, from the input compressed signal, and supplies the high-speed reproduction data to another memory 5. The memory 5 stores the high-speed reproduction data, and at the time of reading, the read control is performed based on the control signal from the output control circuit 6, and the memory 5 outputs the read high-speed reproduction data. Thereafter, the read data for high speed reproduction is given to the terminal b of the changeover switch 3. The changeover switch 3 alternately switches the terminal a and the terminal b on the basis of the switching control signal from the output control circuit 6 to superimpose the compressed signal and the high-speed reproduction data on the recording circuit 7. In this case, in the present embodiment, the output control circuit 6 causes the magnetic tape 8 to have the compressed signal and the high-speed reproduction data in a predetermined arrangement order (recording pattern).
The change-over switch 3 is controlled so as to be recorded on the upper track.

The recording circuit 7 is composed of, for example, an error correction code addition circuit, a modulation circuit, a recording equalization circuit, etc., and the recording circuit 7 performs a process for recording given data. For example, the error correction code addition circuit adds an error correction code to the data, and then the modulation circuit performs modulation by a modulation method suitable for recording. Further, a recording equalization circuit performs waveform equalization processing to convert the signal into a recording signal. The output (recording signal) of the recording circuit 7 is recorded on the tape 8 via a rotary transformer and a magnetic head (not shown).

2 and 3 are explanatory views for explaining the recording pattern in this embodiment, and FIG. 2 shows an example of the structure of one frame of high-speed reproduction data (special reproduction dedicated image data), and FIG. Shows an example of the tape recording pattern in this embodiment.

In this embodiment, the magnetic tape 8 is
Recording is performed in the tape format disclosed in the specification of Japanese Patent Application No. 6-065298. That is, recording tracks are formed on the magnetic tape 8 by a predetermined rotating drum head, and adjacent recording tracks are in reverse azimuth. On each recording track, pilot signals f1, f0, f2, f0, f1, ... Are multiplexed and recorded on the recording data at a 4-track cycle. A high-speed reproduction data area is provided at a predetermined position of the recording track of the magnetic tape 8 to record the high-speed reproduction data. The data area for high-speed playback is set at a position according to the speed multiple, that is, a position on the trace locus when a predetermined speed multiple is traced by the rotating drum head capable of the same trace during recording and playback. is doing.

In this embodiment, for example, as shown in FIG. 2, the data area of one frame of the high-speed reproduction data generated by the special reproduction data generation circuit 4 is changed to the data area 18.
Then, the data area 18 is arbitrarily intermittently divided in the vertical direction, and a, b, c, d, e, f, g, and h are divided.
And the data area of i. That is, if all the data in each data area (a to i data areas) can be reproduced, the data area for high-speed reproduction 1
Therefore, it is possible to reproduce data of one frame of eight. Then, the high-speed reproduction data in the areas a to i obtained by dividing the high-speed reproduction data area of one frame is recorded in the high-speed reproduction data area at a predetermined position on the tape 8. FIG. 3 shows a recording pattern in which the high-speed reproduction data of the areas a to i are recorded in each high-speed reproduction data area.

The recording track in the recording pattern of this embodiment is composed of a normal reproduction data area shown in white as shown in FIG. 3 and a high-speed reproduction data area shown by symbols a to i. . During normal reproduction, normal reproduction data shown in white in the figure and high-speed reproduction data recorded in the high-speed reproduction data area are reproduced. A normal reproduction image is obtained by selecting only the normal reproduction data.
Further, as described above, the pilot signals f1, f0, f2, f0, f1, and
... is recorded in the recording data in a multiplexed manner. in this case,
F0 is recorded on the minus azimuth track, and f1 and f2 are recorded on the plus azimuth track. During reproduction, the levels of the pilot signals f1 and f2 included in the reproduced signal are compared, and control is performed so that the comparison levels match, that is, the track phase is aligned with the track on which the pilot signal f0 is superimposed. In this case, considering the shift of the track phase, the track phase can be matched with the track of the pilot signal f0 every four tracks. This makes it possible to identify the tracks in units of four tracks.

The high-speed reproduction data area shown in FIG. 3 is arranged at a position traced by the rotary drum head during 8-times speed reproduction. One track has at least three high-speed reproduction data areas. That is, these high-speed reproduction data areas are formed by alternately arranging a high-speed reproduction data area in the forward direction and a high-speed reproduction data area in the reverse direction from the start end direction to the end direction of the track. In the data area for high speed reproduction in the forward direction, data for high speed reproduction in the forward direction according to the double speed number is recorded in order,
On the other hand, reverse high speed reproduction data is recorded in reverse in the reverse high speed reproduction data area. That is, in the forward direction high speed reproduction data area, data is recorded in order from the forward direction high speed reproduction data of the area a, and in the reverse direction high speed reproduction data area, the track of the area a and the reverse direction of the track deviated by two tracks are recorded in the reverse direction. From the high-speed reproduction data area, backward high-speed reproduction data of the area i is recorded in order. For example, as shown in FIG.
In the case of double speed, high-speed reproduction data in units of 4 tracks, which is a set of a region, b region and c region, is recorded in 16 tracks for every 4 tracks, and this is similarly recorded for one screen. On the other hand, in the case of fast reverse playback,
Head trace angle opposite to the head trace angle during high-speed playback
Is a double speed, the forward speed is 8 times faster
Therefore, if the double speed number is m, then (m-2) double speed
Number, that is, 6x speed reverse high speed playback (hereinafter -6x speed playback
That is). In this case, as the data for -6x speed reproduction, the data area for 8x speed reproduction, that is, the track in which the area a is arranged at the start end of the track and the track deviated by 2 tracks are sequentially described from the end side of 1 frame data. Record in the same way. Incidentally, in the -6 × speed reproduction, the effective trace is performed every 12 tracks, but in the present embodiment, it is repeatedly recorded over 16 tracks as in the 8 × speed.

Therefore, in the high speed reproduction data area,
The high-speed reproduction data of the same array is recorded every four tracks (hereinafter also referred to as a repeating unit), and (double speed number × 2) tracks (hereinafter also referred to as a repeating track number).
The high-speed playback data is updated every time.

On the other hand, the magnetic tape 8 recorded as described above
Magnetic tape 8 during special playback (high speed playback)
Is traced by a rotating drum head (not shown).
The reproduction signal from the rotary drum head is given to the reproduction circuit 9 and the tracking circuit 10. The reproduction circuit 9 is composed of a reproduction waveform equalization circuit, a demodulation circuit, an error correction circuit, and the like, and performs processing necessary for reproduction on the reproduction signal. For example, the reproduction waveform equalization circuit equalizes the reproduction signal waveform and converts it into digital data. Then, the demodulation circuit performs demodulation so as to obtain the original input data, and further performs error correction by the error correction circuit and supplies the data to the data selection circuit 14 and the data correctness determination circuit 11. The data selection circuit 14 selects only the normal reproduction data from the reproduction signal and outputs it to the memory 16 during the normal reproduction. In addition, the data selection circuit 14
During high-speed reproduction, a reproduction signal of high-speed reproduction data is selected (extracted) from the reproduction signal and output to the memory 16 and the data rearrangement circuit 15. Data correctness determination circuit 11
Determines whether or not the high-speed reproduction data area has been normally reproduced, and outputs a determination signal to the tape drive control circuit 12.

The memory 16 stores the reproduction data selected by the data selection circuit. At this time, if the reproduced data is not reproduced normally, the memory 16 receives the compressed signal at the time of input based on the instruction signal from the data rearrangement circuit 15 regardless of the reproduction order of the data for one screen of high speed reproduction. The data is rearranged and stored in the order of time series, and the reproduction data is output to the output terminal 17 as a unit of one screen. still,
During normal high-speed reproduction or reverse high-speed reproduction, the memory 16 forms data for one screen in high-speed reproduction in the order of reproduction as it is, and outputs reproduction data.

The tracking circuit 10 compares the levels of the pilot signals f1 and f2 included in the reproduced signal and outputs a signal for adjusting the phase to the track on which the pilot signal f0 is recorded, to the tape drive control circuit 12. . The tape drive control circuit 12 applies a control signal to the capstan 13 so that the tape reproduction speed is based on the signal from the tracking circuit and controls the tape reproduction speed. That is, the tape drive control circuit 12 generates a control signal for running the magnetic tape 8 at the normal reproduction speed to achieve on-track when normal reproduction is designated from the outside. . Further, for example, when a high speed reproduction of a predetermined double speed (including a reverse high speed reproduction) is designated from the outside, the tape drive control circuit 12 sends a control signal for running the magnetic tape 8 at the specified double speed to the capstan. It outputs to 13. Then, the tracking circuit 10 supplies a signal for adjusting the track from the reproduction signal in this case to the tape drive control circuit 12 to achieve on-track.

Further, in this embodiment, during high speed reproduction, the tape drive control circuit 12 causes the data correctness determination circuit 11 to operate.
The tape running is controlled on the basis of the discrimination signal from. That is, when the discriminating signal indicates that the reproduction of the high speed reproduction data area is not normally performed during the high speed reproduction, the tape drive control circuit 12
Is a specified speed number, k does not exceed (k / 2) -1 (n + 0.5) (n is an integer). The magnetic outputs a control signal to the capstan 13 for running the tape 8. It is like this. For example, when the 8 × speed reproduction is designated from the outside, the tape drive control circuit 12 sends a control signal for performing the 2.5 × speed reproduction when the reproduction of the high speed reproduction data area is not normally performed. Occur.

During reverse high speed reproduction, the tape drive control circuit 12 similarly does not exceed (k / 2) -1 (n).
At a speed of +0.5) (n is an integer), the magnetism outputs a control signal for running the tape 8 to the capstan 13. That is, in the case where the forward reproduction is the 8 × speed reproduction, when the reproduction of the backward high-speed reproduction data area is not normally performed, the data drive control circuit 12 outputs −
A control signal for performing 2.5 × speed reproduction is generated.

Next, the operation of the embodiment thus constructed will be described with reference to FIGS. 4 to 7 and Tables 1 and 2 below. FIG. 4 is an explanatory diagram for explaining a head trace when 8 × speed is designated, and FIG. 5 is an explanatory diagram for explaining a head trace when −6 × speed is designated. In addition, FIG. 6 shows a case in which (k / 2) -1 is not exceeded and (n + 0.5) double speed reproduction is set when the head trace is different between recording and reproducing when 8x speed is designated. FIG. 7 is an explanatory diagram for explaining the head trace, and FIG. 7 is an explanatory diagram for explaining the head trace when the phase of the head trace according to FIG. 6 is shifted. Table 1 is for explaining the state of the reproduced signal by the head trace according to FIG. 6, and Table 2 is an explanatory diagram for explaining the state of the reproduced signal by the head trace according to FIG.

Now, it is assumed that normal reproduction / reproduction is designated when reproducing the magnetic tape 8 on which data is recorded in a recording pattern as shown in FIG. 3 by the magnetic recording apparatus of the present embodiment. In this case, the tape drive control circuit 12
Outputs to the capstan 13 a control signal for running the magnetic tape 8 at the normal reproduction speed. As a result, the magnetic tape 8 runs at the normal reproduction speed, and the recording track is traced by the rotating drum head (not shown).

The tracking circuit 10 compares the reproduction levels of the pilot signals f1 and f2 included in the reproduction signal.
When the pilot is unbalanced during normal reproduction, the track phases are set so that the reproduction levels of the pilot signals f1 and f2 coincide, that is, the track phase coincides with the track in which the pilot signal f0 is multiplexed. The tape drive control circuit 1 outputs a signal for shifting
Give to 2. The tape drive control circuit 12 gives a control signal based on the signal to the capstan 13. This achieves on-track.

The reproduction signal is waveform-equalized by the reproduction circuit 9, converted into digital data, further demodulated and error-corrected and given to the data selection circuit 14. Since the reproduction signal is the reproduction of the high-speed reproduction data in the high-speed reproduction data area and the normal reproduction data together,
The data selection circuit 14 selects normal reproduction data, and the reproduction signal is output via the memory 16 and the output terminal 17.

Next, it is assumed that high speed reproduction of 8 times speed is designated. In this case, the tape drive control circuit 12 outputs to the capstan 13 a control signal for running the magnetic tape 8 at a high reproduction speed of 8 times. As a result, the magnetic tape 8 runs at a reproduction speed of 8 times, and the recording track is traced by the rotating drum head (not shown) as shown in FIG.

The tracking circuit 10 compares the reproduction levels of the pilot signals f1 and f2 included in the reproduction signal.
When there is a pilot imbalance during the 8 × speed reproduction, the track phase is adjusted so that the reproduction levels of the pilot signals f1 and f2 match, that is, the track phase matches the track in which the pilot signal f0 is multiplexed. Is applied to the tape drive control circuit 12. The tape drive control circuit 12 gives a control signal based on the signal to the capstan 13. This allows
Achieve on-track. Then, as shown in FIG. 4, the minus azimuth head sequentially reproduces the high-speed reproduction data corresponding to the areas a, b, and c in the high-speed reproduction data area by the trace 301. Then 16
Head trace every other track, trace 302,
The head trace 303 sequentially reproduces the high-speed reproduction data in the area d, the area e, the area f, ...

The reproduced signal is waveform-equalized by the reproducing circuit 9, converted into digital data, further demodulated and error-corrected and given to the data selection circuit 14. The data selection circuit 14 selects high-speed reproduction data from the reproduced digital data and outputs it to the memory 16. Then trace 3
The reproduced digital data from 01 to 303 is stored in the memory 1
The data is stored in No. 6, and the normal one screen of high-speed reproduction data is obtained in the reproduced order and is output through the output terminal 17. As a result, it becomes possible to favorably perform high-speed reproduction at 8 times speed.

Next, it is assumed that -6x speed is designated.
In this case, the tape drive control circuit 12 outputs to the capstan 13 a control signal for running the magnetic tape 8 at a high reproduction speed of -6 times. As a result, the magnetic tape 8 travels in the reverse direction at (8-2) times speed, that is, at -6 times speed, and the rotary drum head not shown in FIG.
The recording track is traced as shown in FIG.

The tracking circuit 10 similarly compares the reproduction levels of the pilot signals f1 and f2 included in the reproduction signal. When the pilot is unbalanced during -6 × speed reproduction, the track is adjusted so that the reproduction levels of the pilot signals f1 and f2 match, that is, the track phase matches the track in which the pilot signal f0 is multiplexed. A signal for shifting the phase is given to the tape drive control circuit 12. The tape drive control circuit 12 gives a control signal based on the signal to the capstan 13. This achieves on-track. Then, as shown in FIG. 5, the minus azimuth head sequentially reproduces the high-speed reproduction data corresponding to the areas a, b, and c in the high-speed reproduction data area by the trace 401. Thereafter, head tracing is performed every 16 tracks, and the high-speed reproduction data of the d area, the e area, the f area, ...

The reproduction signal is waveform-equalized by the reproduction circuit 9, converted into digital data, further demodulated and error-corrected and given to the data selection circuit 14. The data selection circuit 14 selects high-speed reproduction data from the reproduced digital data and outputs it to the memory 16. Then trace 4
The reproduced digital data from 01 to 403 is stored in the memory 1
The data is stored in 6 and the normal high-speed reverse direction reproduction data for one screen is obtained in the order of reproduction and output terminal 17
Output via. As a result, the rearrangement of the reproduction data at the time of high-speed reproduction in the reverse direction is unnecessary, and it is possible to favorably −6
It is possible to perform double speed high speed reproduction.

By the way, due to the track bending of other VCRs or the difference in the structure of the rotary drum head, the pattern of the recording track and the trace pattern of the reproducing head differ, and the high-speed reproducing data area can be normally reproduced. Sometimes you can't. The operation in this case will be described.

Now, although high-speed reproduction is performed by designating 8-times speed reproduction, it is considered that the high-speed reproduction data area cannot be normally reproduced due to the difference between the recording track pattern and the reproducing head trace pattern. To do. In this case, the data correctness determination circuit 11 outputs a determination signal indicating that normal reproduction is not performed, to the tape drive control circuit 12.

Then, the tape drive control circuit 12 ignores the signal for achieving the on-track from the tracking circuit 10 and does not exceed the (specified multiple speed k / 2) -1 (n + 0.5) multiple speed, that is, 2 A control signal for running the magnetic tape 8 at 5 × speed is output to the capstan 13. That is, during high-speed reproduction in this case, a non-tracking state in which tracking is not performed is performed, and the magnetic tape 8 runs at 2.5 times speed. Therefore, the trace locus by the minus azimuth head in this case is as shown in FIG. 6, for example. That is, as shown in FIG. 6, the trace 501 of the minus azimuth head reproduces the lowermost end of the first track in the repeating unit, and then reproduces the central portion of the same track. That is, FIG.
As shown in, the areas a and h of the high-speed reproduction data area are reproduced. The reproduction signal is waveform-equalized by the reproduction circuit 9. The envelope of this reproduction signal is as shown in Table 1. The numbers in Table 1 indicate trace numbers, and
Reference characters i to i indicate respective high speed reproduction data areas. Also,
The symbols ◯, Δ, and ▽ correspond to the envelopes of the reproduced signals in the respective areas obtained by tracing. For example, the symbol ○ indicates the maximum amplitude of the envelope, and the symbol Δ indicates that the amplitude of the reproduced signal envelope gradually decreases. State, symbol ▽
Shows the state where the amplitude of the envelope of the reproduced signal gradually increases.

[0051]

[Table 1] That is, in the trace 501 as shown in Table 1 above, a
For the area, all high-speed playback data is played, and h
As for the area, only the lower part of the high speed reproduction data is reproduced.

Thereafter, the minus azimuth head reproduces the central portion of the seventh track from the left in FIG. 6 by the trace 502, and then reproduces the uppermost end of the same track. That is, the b area and i area of the high speed reproduction data area are reproduced. The reproduction signal is waveform-equalized by the reproduction circuit 9. The envelope of this reproduction signal is as shown in Table 1. That is, as shown in Table 1, in the trace 502, only the upper portion of the high speed reproduction data is reproduced for the b area, and all the high speed reproduction data is reproduced for the i area. Next, the minus azimuth head reproduces the bottom end of the eleventh track from the left in FIG. 6 by the trace 503, and then reproduces the central portion of the same track. That is, the b area and the g area of the high speed reproduction data area are reproduced. The reproduction signal is waveform-equalized by the reproduction circuit 9. The envelope of this reproduction signal is as shown in Table 1. That is, as shown in Table 1, in the trace 503, only the lower part of the high speed reproduction data is reproduced for the b area, and all the high speed reproduction data is reproduced for the g area. Thereafter, the traces 504 to 510 are performed 10 times in this manner. Then, the relationship between each head trace and the envelope of the reproduced signal is as shown in Table 1.

For example, if normal reproduction data can be obtained when the maximum amplitude of the envelope waveform of the reproduction signal is ½ or more, the area where normal reproduction data can be obtained is not limited to the symbol ○ in Table 1. That is, the symbol Δ and the symbol ▽ are added. When these reproduced portions are combined for each corresponding area, a normal reproduced signal can be obtained.
That is, 1 times by 10 times of traces 501 to 510
It is possible to normally reproduce all the high-speed reproduction data areas for the screen (areas a to i). In the high-speed reproduction data area, the same high-speed reproduction data for one screen in the forward and reverse directions is recorded over 48 tracks, so the high-speed reproduction data is provided at the same position on each recording track. Thus, regardless of the position, it is possible to reliably reproduce the high speed reproduction data by synthesizing the reproduction data by the traces 501 to 510. That is, even when the track bend is different between the time of recording and the time of reproduction, or even when the trace pattern is different due to the difference in the head configuration between the time of recording and the time of reproduction, it is possible to reliably reproduce the high-speed reproduction data. it can. Also, during reverse high speed reproduction, the reverse reproduction data can be similarly reproduced.

The data selection circuit 14 selects the high speed reproduction data from the reproduced digital data and outputs it to the memory 16. Thereafter, the reproduced digital data by the traces 501 to 510 is stored in the memory 16, and the compressed signals for one screen are rearranged in order in time series on the basis of the control signal from the data rearrangement circuit 15 to synthesize the compressed digital data. The high speed reproduction data is obtained and output through the output terminal 17. As a result, even when 8x speed is impossible, 2.
It becomes possible to perform high speed reproduction of 5 times speed. That is, in the prior art, in this case, the multiple speed is about ¼, but according to the present embodiment, the multiple speed at the time of high speed reproduction can be improved.

In the above high-speed reproduction, since the tracking is not performed, that is, the reproduction is performed without tracking, only the trace interval and the slope of the trace are defined, but the phase between the track and the trace locus is defined. It may shift. Even in this case, the pattern of the recording track and the trace pattern of the reproducing head are different,
Assuming that the high-speed reproduction data area cannot be normally reproduced, the data correctness determination circuit 11 outputs a determination signal indicating that normal reproduction is not performed to the tape drive control circuit 12.

Then, the tape drive control circuit 12 ignores the signal for achieving the on-track from the tracking circuit 10 and does not exceed the (specified multiple speed number k / 2) -1 (n + 0.5) multiple speed, that is, 2 A control signal for running the magnetic tape 8 at 5 × speed is output to the capstan 13. That is, during high-speed reproduction in this case, a non-tracking state in which tracking is not performed is performed, and the magnetic tape 8 runs at 2.5 times speed. Therefore, the trace locus by the minus azimuth head in this case is as shown in FIG. 7, for example. That is, as shown in FIG. 7, the trace 601 of the minus azimuth head reproduces the lowermost end of the first track and then the uppermost end of the third track in the repeating unit. That is, as shown in FIG. 7, area a and i of the high-speed reproduction data area
Play the area. The reproduction signal is waveform-equalized by the reproduction circuit 9. The envelope of this reproduction signal is shown in Table 2.

[0057]

[Table 2] That is, in the trace 601, as shown in Table 2 above, a
For the area, the lower part of the high-speed reproduction data is reproduced, and for the i area, only the upper part of the high-speed reproduction data is reproduced.

After that, the minus azimuth head reproduces the lowermost end and the central portion of the seventh track from the left in FIG. 7 by the trace 602, and then reproduces the uppermost end of the same track. That is, the g area of the data area for high speed reproduction,
Reproduce the area b and the area i. The reproduction signal is waveform-equalized by the reproduction circuit 9. The envelope of this reproduction signal is shown in Table 2. That is, as shown in Table 2, in the trace 602, the upper part of the high speed reproduction data is reproduced for the g area, all the high speed reproduction data is reproduced for the b area, and the high speed reproduction is performed for the i area. The lower part of the data will be reproduced. Thereafter, the traces 604 to 610 are traced in this manner, that is, the traces 601 to 610
Trace 0 times. Then, the relationship between each head trace and the envelope of the reproduced signal is as shown in Table 2.

For example, assuming that normal reproduction data can be obtained when the maximum amplitude of the envelope waveform of the reproduction signal is ½ or more, the area where normal reproduction data can be obtained is not limited to the symbol ○ in Table 1. That is, the symbol Δ and the symbol ▽ are added. When these reproduced portions are combined for each corresponding area, a normal reproduced signal can be obtained.
That is, 10 traces 601 to 610 make 1
It is possible to normally reproduce all the high-speed reproduction data areas for the screen (areas a to i). In the high-speed reproduction data area, the same high-speed reproduction data for one screen in the forward and reverse directions is recorded over 48 tracks, so the high-speed reproduction data is provided at the same position on each recording track. Thus, regardless of the position, it is possible to reliably reproduce the high speed reproduction data by synthesizing the reproduction data by the traces 501 to 510. That is, even when the track bend is different between the time of recording and the time of reproduction, or even when the trace pattern is different due to the difference in the head configuration between the time of recording and the time of reproduction, it is possible to reliably reproduce the high-speed reproduction data. it can. Also, during reverse high speed reproduction, the reverse reproduction data can be similarly reproduced.

The data selection circuit 14 selects high speed reproduction data from the reproduced digital data and outputs it to the memory 16. Thereafter, the reproduced digital data by the traces 601 to 610 is stored in the memory 16, and the compressed signals for one screen are rearranged in order of time series based on the control signal from the data rearrangement circuit 15 so as to be synthesized. The high speed reproduction data is obtained and output through the output terminal 17. As a result, even if the 8 × speed is impossible and the phase of the track and the trace locus are further deviated, the high speed reproduction of 2.5 × speed can be performed.

Other functions and effects are similar to those of the example shown in FIG.

As described above, in the present embodiment, during high-speed reproduction in the reverse direction, the high-speed reproduction data has the recording track pattern in which the reverse-direction high-speed reproduction data is recorded in reverse. It is possible to reproduce backward high-speed reproduction data without rearranging. Also,
When the high-speed reproduction data area cannot be reproduced normally, at least 10 times of tracing can be performed by the same azimuth head within the number of repetitive tracks (within 48 tracks) (n + 0.5). Therefore, high-speed reproduction data can be surely reproduced by tracing 10 times by the same azimuth head, and reverse reproduction data can be surely reproduced even in reverse high-speed reproduction. As a result, the playback speed can be improved as compared with the conventional one, and reliable forward high-speed playback or reverse high-speed playback that is not affected by device compatibility or the like can be performed.

In this embodiment, (n + 0.5)
At the time of double speed reproduction, n was set to (double speed number / 2) -1, but n may be an integer equal to or less than this value. Also, the smaller the double speed number, the smaller the angle at which the trace locus crosses the track, and the smaller the inclination of the envelope, making it easier to obtain normal reproduction data. Therefore, when it is determined that the high-speed reproduction data area becomes small and the high-speed reproduction data is not normally reproduced, first, n is set to (double speed number / 2) -1, and in this case, the high-speed reproduction is performed. The double speed number may be sequentially reduced depending on whether or not the usage data is normally reproduced.

Further, in the present embodiment, it was explained that at least three high-speed reproduction data areas in the forward direction and the reverse direction in the high-speed reproduction data area in one track were constituted. However, the present invention is not limited to this. Never be
It is also possible to provide a plurality of more high-speed reproduction data areas.

Further, in the present embodiment, in order to distinguish the high-speed reproduction data for one screen from the high-speed reproduction data for the next one screen, an identification signal for identification is used for the high-speed reproduction. It may be recorded so as to be superimposed on the data.

[0066]

As described above, according to the present invention,
Even in the case of reverse high speed reproduction, by using the recording track pattern of the present embodiment, it is possible to trace the reverse high speed reproduction data area, and it becomes unnecessary to rearrange the reverse reproduction data. Further, even when the head trace loci differ during recording and reproduction, it is possible to reliably trace the high-speed reproduction data area including the reverse-direction high-speed reproduction data area, and to perform high-speed reproduction in the forward and reverse directions. It has an effect that an image can be reproduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a magnetic recording device and a magnetic reproducing device according to the present invention.

FIG. 2 is a configuration diagram showing a configuration of trick play data for one screen.

FIG. 3 is a diagram showing a data recording pattern in the present embodiment.

FIG. 4 is an explanatory diagram showing a trace locus during high-speed reproduction.

FIG. 5 is an explanatory diagram showing a trace locus during reverse high speed reproduction.

FIG. 6 is an explanatory diagram showing a trace locus during high-speed reproduction in a non-tracking state.

FIG. 7 is an explanatory diagram showing a trace locus during high-speed reproduction in a non-tracking state.

[Explanation of symbols]

1, 5, 16 ... Memory, 4 ... Special reproduction day generation circuit, 6
... output control circuit, 7 ... recording circuit, 9 ... reproducing circuit, 10 ...
Tracking circuit, 11 ... Data correctness determination circuit, 12 ...
Tape drive control circuit, 14 ... Data selection circuit, 15 ... Data rearrangement circuit.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-261279 (JP, A) JP-A-5-276484 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 20/10-20/16 H04N 5/91-5/95

Claims (5)

(57) [Claims] 1. When a track is formed by a head on a magnetic tape, the tracking adjustment of the head is performed during reproduction.
And a normal reproduction of the head of each track for every predetermined number of tracks.
In a magnetic recording device for forming a high-speed reproduction data area at a plurality of predetermined positions in the trace direction at the time , the first high-speed reproduction high-speed reproduction data and the second high-speed reproduction data region
Given fast speed reverse high-speed reproduction data, a plurality of high-speed reproduction data area of each track of the head through
Alternating forward or backward areas in the trace direction during normal playback
Set the direction area, sequentially recording the first multiple speed forward high-speed reproduction said first speed multiple of the high-speed playback data in the forward direction to the forward area of the plurality of tracks which the head traces when to together, the head sequentially records for high-speed playback data in the opposite direction of the plurality of the second multiple speed <br/> in the reverse area of the track to be traced on the second multiple speed of fast reverse playback A magnetic recording apparatus comprising: 2. The data recorded in the high-speed playback data area includes a plurality of data areas that compose one screen.
The recording means divides each track for each of the predetermined number of tracks.
In the rack, the data areas for high-speed playback are
Data of different data areas are recorded in
The same data in the data area is recorded for each predetermined number of tracks.
However, all the data in the multiple data areas that make up one screen are
Data before the high-speed playback in the forward direction or high-speed playback in the reverse direction.
The forward region or the backward region traced by the head
The magnetic recording apparatus according to claim 1, wherein the magnetic recording is sequentially performed on the magnetic recording medium. 3. A plurality of tracks of the predetermined number of tracks
Regarding the recorded data for high speed reproduction in the forward direction,
Repeated recording over the first double speed × 2 tracks
And recorded on a plurality of tracks of the predetermined number of tracks.
For high-speed playback data in the reverse direction,
Repeated recording over speed + 2) x 2 tracks
The magnetic recording device according to claim 2, wherein 4. The data for forward high speed reproduction and the data for reverse high speed reproduction are recorded so as to be reproduced from the data at one end and the other end of the screen, respectively. The magnetic recording device according to claim 2. 5. The method according to any one of claims 1 to 4.
Plays a magnetic tape recorded by a magnetic recording device
The thing (Number of double speed / 2-1) (n + 0.5) Double speed (n
Is an integer) and the magnetic tape is run
The high-speed playback data in the forward or reverse direction recorded in
A regeneration means The output from this playback means is rearranged and output in chronological order.
Magnetic reproduction characterized by comprising a rearrangement means
apparatus.