JPH08214252A - System for recording compressed moving image data and its record reproducing system - Google Patents

Abstract

PURPOSE: To attain a recording pattern for specific reproducing data simplified in its tracking control and corresponding to plural recording modes having respectively different tape speeds at the time of recording inter-frame encoded moving image data. CONSTITUTION: The same specific reproducing data of N pairs each of which consists of a track of ± azimuth are recorded in respective recording areas 11, 12 and normal reproducing moving image data are recorded in other data recording areas. The value of N is fixed regardless of recording modes. Thereby specific reproducing from ±1.5 times speed up to ±N/2 times speed stepwise changed can be attained only by the simplest speed control for tracking control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording system and a recording / reproducing system of compression-encoded moving image data, and in particular, a special recording area is provided separately from an area for recording the compressed moving image data, and a special recording area is provided. The present invention relates to a method of recording image data for reproduction and a recording / reproduction method.

[0002]

2. Description of the Related Art Conventionally, in a device which digitally records a moving image bit-compressed by using an image coding technique, intraframe coding has been used in consideration of special reproduction, editing, and simplification of a compression circuit. . However, since a high compression rate can be obtained by the inter-frame predictive coding, the inter-frame predictive coding is becoming mainstream in applications such as digital TV broadcasting and transmission via a network.
Therefore, a compressed moving image recording apparatus for recording a moving image compressed by this interframe predictive coding will be required in the future.

A problem when recording a moving image coded by inter-frame predictive coding is the image quality during special reproduction. That is, the inter-frame predictive coding is to encode the difference from the inter-frame predicted value, and it is premised that the data of the reference frame is known at the time of decoding, but the data is scattered at the time of special reproduction. Since it is only regenerated, this premise no longer holds.

In inter-frame predictive coding, a frame called an intra frame, which encodes the value itself without taking the difference from the predicted value, is inserted for every predetermined number of frames.
In addition, the image data is discrete cosine transform (DC
It is general that the DC component is converted into frequency components from the high frequency component by orthogonal transformation such as T) and then variable length coding is performed. Can be decrypted. Therefore, conventionally, a dedicated area for recording the low frequency component of the intra frame is provided in a portion along the trajectory of the head during special reproduction, and the reproduced image can be decoded using the data reproduced from this area during special reproduction. Etc. have been proposed. On the other hand, an apparatus for selecting, recording, and reproducing a plurality of digital image signals having different compression rates of encoding is disclosed in, for example, Japanese Patent Application Laid-Open No. HEI-1.
-258255. It has multiple recording modes, encodes information signals into digital data with different transmission rates according to the modes, converts the encoded digital data into signals with a constant recording rate by time axis processing, and encodes the encoded digital data. The signal is recorded at a constant rate, which is time-axis processed at the tape speed according to the data transmission rate.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the prior art disclosed in Japanese Patent No. 585, etc., data for special reproduction is recorded only in an area along the trajectory of the head during special reproduction, so complicated tracking control is required to reliably scan the recording area. There was a problem that needed.
That is, the normal tracking control includes a speed control for controlling the tape running speed and a phase control for controlling the head scanning position so that the scanning position of the head is located at the center of the track. The track selection control for scanning the recording area is required.

Further, in a device provided with a plurality of recording modes having different tape speeds, as disclosed in Japanese Patent Laid-Open No. 1-258255, etc., a method for efficiently performing special reproduction corresponding to each recording mode. Was also not considered. That is, since the scanning locus of the head differs depending on the recording mode, in the conventional technique disclosed in Japanese Patent Laid-Open No. 4-346585, the recording area of the special reproduction data differs depending on the recording mode, and the process becomes complicated. There was a problem that the scale would also increase.

The object of the present invention is to solve the above-mentioned problems of the prior art, and the tracking control is the current analog V for home use.
Another object of the present invention is to provide a recording system and a recording / reproducing system of moving image data which are as simple as TR and enable special reproduction corresponding to a plurality of recording modes.

[0008]

In order to achieve the above object, in the present invention, special reproduction data is arranged in a predetermined recording area of each track, and the same data for N tracks is recorded in each of positive azimuth and negative azimuth. I chose Then, the data is updated for each of the N sets of tracks, and the value of this N is constant regardless of the recording mode.

[0009]

Since the same data for N tracks is recorded for each of positive azimuth and negative azimuth, only the simplest speed control for tracking control is used in any recording mode, and the normal reproduction speed is ± 1.5 / J (J is a natural number). ) Double speed, ± 2.5 / J double speed, ± 3.5 / J double speed to ± N / 2
This special reproduction data can be reproduced stepwise up to / J times the speed.

[0010]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a recording pattern diagram on a tape showing an embodiment of a recording system of compressed moving image data according to the present invention. Here, 1 is a magnetic tape, and 10a and 10b are recording tracks, which are alternately formed by a −azimuth head and a + azimuth head, respectively. Reference numerals 11 and 12 are recording areas for special reproduction image data, and N sets of the same data are recorded with one set of − and + azimuth tracks.
Compressed moving image data for normal reproduction is recorded in the other data recording areas, and subcode data is recorded in the subcode recording areas.

In FIG. 1, the recording track stands upright with respect to the longitudinal direction of the tape, but the recording track is generally inclined. This is drawn vertically for easy viewing of the drawing, and the effect of the present invention is not lost even if the recording track is inclined.

The first feature of this embodiment is that N sets (for example, N = 15) of the same data are recorded in the recording regions 11 and 12 of the special reproduction image data, with one set of − and + azimuth tracks. This value of N is constant regardless of the recording mode. As a result, only the simplest speed control as the tracking control enables stepwise reproduction from the normal reproduction speed of ± 1.5 times to ± N / 2 (for example, ± 7.5) times. This will be described in detail later.

The second feature of this embodiment is that the following relationship is established between the special reproduction image data recording areas 11 and 12 and the subcode recording area.

That is, the track length corresponding to the winding angle of 180 degrees is L, and the speed factor in the positive (+) direction with respect to the normal reproduction speed is M (M is an integer of N / 2 or more and N or less, for example, M = 13), the distance between the center of the areas 11 and 12 and the center of the subcode recording area is β, and the track interval between the track for reading the special reproduction image data and the track for reading the subcode data is k. The relationship is expressed by the equation 1.

[0016]

## EQU1 ## β≈L ÷ (M-1) × k Note that β is set to L / 2 or less in consideration of track linearity and tracking error.

When the recording length of the areas 11 and 12 in the track direction is α, the relationship between this α and the double speed number M is expressed by Equation 2.

[0018]

[Expression 2] α ≦ INT [L ÷ (M−1)] where INT [·] is a function of integerization.

Since the recorded data is generally in a block structure, the number of blocks is also related to the track length L, the length α of the special reproduction areas 11 and 12, and the distance β between the special reproduction areas 11 and 12 and the subcode area. Stipulated in.

When the phase control is added to the speed control as the tracking control by giving the above relationship, the special reproduction image data recorded in the areas 11 and 12 is + M.
It is possible to read subcode data recorded in the subcode recording area while reproducing at double speed and-(M-2) times speed.

Next, the first feature of this embodiment will be described with reference to FIGS.
Will be explained.

FIG. 2 is a diagram showing a scanning state of the −azimuth head 3a and the + azimuth head 3b facing each other by 180 degrees at the time of N / 2 (7.5) speed reproduction, (A).
Shows the case of the positive (+) direction, and (B) shows the case of the reverse (-) direction.
Here, the solid lines 31a and 41a show the scanning locus of the head 3a, and the broken lines 31b and 41b show the scanning locus of the head 3b, and these are tracking-controlled only by speed control. The special reproduction data recorded in the areas 11 and 12 are read out once every two rotations of + and −. That is, the special reproduction data is + and-N respectively.
(15) Since the same data is recorded on the track, even if not all the data can be read in the first scan, the remaining data can be read in the next scan. And
A reproduced image is constructed from the read data.

FIG. 3 is a waveform diagram showing this state.
(A) is a reproduction envelope in the first scanning,
(B) is a reproduction envelope in the second scanning,
(C) is the data read by the first scan, and (D) is 2
The data read by the second scan, and (E) shows the data read by the second scan. In this way, since the double speed number is 7.5, the scanning is shifted by one track in the first and second scanning, and the portion that could not be read in the first scanning is always read in the second scanning. Therefore, no matter what the tracking phase is, all the data can be read without fail in two scans. The same applies to subcode data. And this is N / 2 (7.5)
Not limited to double speed, 1.5 times, 2.5 times, 3.5 times N
It is possible to step up to / 2 times, and in both forward and reverse directions. Although N is an odd number in this embodiment, it may be an even number. However, in this case, (N-1) / 2 times speed is the maximum speed.

As described above, in the present embodiment, only the simplest speed control as the tracking control enables the stepwise special reproduction at a relatively low speed from ± 1.5 times speed to ± N / 2 times speed. Moreover, by adding the phase control, special reproduction can be performed at a high speed of + M times speed and − (M−2) times speed. Moreover, the subcode data recorded in the subcode recording area can be read while reproducing the special reproduction data.

FIG. 4 is a block diagram showing an example of the arrangement of a recording apparatus which realizes the recording method according to the present invention. Where 1
Is a magnetic tape, 2 is a rotary drum, 3a and 3b are magnetic heads, 101 is an antenna, 102 is an RF demodulation circuit, 103
Is a priority data selection circuit, 104 is a special reproduction data memory, 105 is a main data memory, 106 is a read control circuit, 107 is a time division multiplexing circuit, 108 is an arrangement pattern control circuit, 109 is a synchronous block forming circuit, and 110 is recording modulation. Circuit.

The antenna 101 receives a broadcast signal of moving image data compression-coded by interframe prediction and orthogonal transformation, and an RF demodulator 102 demodulates it. The moving image data includes a frame called an intra frame, which has been subjected to orthogonal transformation as it is without taking a difference from the inter-frame prediction, for every predetermined number of frames. In double-speed playback, not all data are available, so data that is the difference from inter-frame prediction cannot be used, and only intra-frame data can be used. The data of each frame is D after orthogonal transformation.
Although the coefficient data from the C component to the high frequency component is encoded by the variable length code, it is possible to reconstruct an image of a certain image quality by using only the low frequency component. The priority data selection circuit 103 extracts intra-frame data from the demodulated moving image data in an amount corresponding to the size of the special reproduction data recording area from the low frequency side and stores it in the special reproduction data memory 104. .

On the other hand, the demodulated moving image data is stored in the main data memory 105. The arrangement pattern control circuit 108 generates a control signal according to the arrangement pattern of the recording area of the special reproduction data, and controls the memory reading and the time division multiplexing so that the desired pattern is realized. The data multiplexed by the time division multiplexing circuit 107 is added with a parity code and a synchronization code for error correction in the synchronization block forming circuit 109, recorded and modulated by the recording modulation circuit 110, and supplied to the magnetic heads 3a and 3b.

The magnetic heads 3a and 3b are arranged on the rotary drum 2 so as to face each other by 180 degrees, and one track is rotated by half a rotation of the magnetic tape 1 wound around the magnetic tape 1.
+ Recording is performed while alternately forming azimuth. Note that Rd indicates the rotation speed of the rotary drum 2, and Vt indicates the running speed of the magnetic tape 1.

Hereinafter, a method for selecting, recording and reproducing a plurality of digital image signals having a plurality of recording modes and having different compression rates in the recording apparatus shown in FIG. 4 will be described.

FIG. 5 is a waveform diagram showing the timing of the recording signal in each recording mode. Here, (A)
Indicates the rotation timing of the rotary drum 2, and the low level period is recorded by the magnetic head 3a, and the high level period is recorded by the magnetic head 3b. At this time, the rotation speed Rd of the rotary drum 2 is constant regardless of the recording mode. (B) is a standard mode (hereinafter, SP
(Referred to as “mode”), and the recording is performed by alternately using the magnetic heads 3a and 3b every half rotation of the rotating drum 2 as described above. (C) is 3 for SP mode
Double the time, that is, the recording mode of the signal whose transmission rate of the received digital image signal is 1/3 of the standard (hereinafter referred to as L
This is a waveform of a recording signal in the P3 mode). In this case, the magnetic head 3 is rotated every 3/2 rotation of the rotary drum 2.
Recording is performed by alternately using a and 3b. At this time, the running speed Vt of the magnetic tape 1 is 1 of the running speed in the SP mode.
Set to / 3. Further, (D) is a waveform of a recording signal in a long time mode (hereinafter, referred to as LP5 mode) which is 5 times as large as that in the SP mode. Recording is performed by alternately using 3a and 3b. The running speed Vt of the magnetic tape 1 is set to 1/5 of the running speed in the SP mode.

The present invention is characterized in that in the recording / reproducing system having such a plurality of recording modes, the number of repetitions N of the special reproduction data is constant regardless of the recording modes. This not only simplifies the processing circuit, but also has the effect of increasing the possible double speed number of special reproduction in the long time mode.

Table 1 shows each recording mode.
The search speed at the time of special reproduction which is possible in this embodiment is shown.

[0033]

[Table 1]

Here, all the values in the table are absolute values with the tape speed during recording and normal reproduction in the SP mode as 1 (reference). The SP mode is shown in Fig. 2 first.
As described above, it is possible in steps from ± 1.5 times speed to ± N / 2 times speed. Needless to say, the simplest speed control is sufficient for tracking control. L
For the P3 mode, not only from ± 1.5 times the speed to ± N / 2 times the speed, but also to 1/2 of that, ± 1.5 / 2 times the speed to ± N /
It becomes possible to step from 4 × speed and 1/3 ± 1.5 / 3 × speed to ± N / 6 × speed. Similarly, LP
For the 5 modes, not only ± 1.5 times the speed to ± N / 2 times the speed, but also ½ of that, ± 1.5 / 2 times the speed to ± N / 4 times.
Double speed, ± 1.5 / 3 times speed of 1/3 to ± N / 6 times speed, 1
± 1.5 / 4 times speed of / 4 to ± N / 8 times speed, and 1/5
From ± 1.5 / 5 times the speed to ± N / 10 times the speed becomes possible.

FIG. 6 shows the forward direction + N / 4 (7.5 / 2 = 3.
75) A diagram showing a state of head scanning during double speed special reproduction. Here, the scanning locus of only −azimuth head 3a is shown, but it goes without saying that the scanning locus of + azimuth head 3b is also the same. Solid line 32a
Indicates the case of + N / 4 (3.75) speed reproduction, and the double-dashed line 31a indicates the case of + N / 2 (7.5) speed reproduction. Needless to say, these are tracking-controlled only by speed control. At the time of + N / 2 (7.5) double speed reproduction, as described in FIG. 2A, the special reproduction data recorded in the areas 11 and 12 is rotated once every two revolutions.
It is read at a rate of once, and a reproduced image is constructed from the read data. -Direction and ± 1.5 times speed ± (N / 2
-1) The same applies to the case of double speed.

In the case of + N / 4 (3.75) speed reproduction, the scanning is shifted by one track every two rotations, and the portion that could not be read by the first scanning is always scanned by the second scanning. It will be readable. Therefore, no matter what the tracking phase is, all data can be read without fail by scanning every two rotations, and a reproduced image is constructed from the read data. -Direction and ± 1.5 / 2x speed ±
The same applies to the case of (N / 2-1) / 2 times speed.

FIG. 7 shows the forward direction + N / 6 (7.5 / 3 = 2.
5) A diagram showing a state of head scanning at the time of special reproduction at double speed, and like FIG. 6, shows a scanning locus of only −azimuth head 3a. Here, the solid line 33a is + N / 6
(2.5) In the case of double speed reproduction, 31a indicated by a chain double-dashed line
Indicates the case of + N / 2 (7.5) double speed reproduction as a reference. The + N / 2 (7.5) double speed reproduction is as described above. In the case of + N / 6 (2.5) double speed reproduction, the scanning is shifted by one track every three rotations as described above, and the portion that could not be read by the first scanning is always read by the scanning after three rotations. Become. Therefore, regardless of the tracking phase, all data can be read without fail by scanning every three rotations, and a reproduced image is constructed from the read data. -Direction and ± 1.5 / 3 times speed ±
The same applies to the case of (N / 2-1) / 3 times speed.

As described above, the scanning in FIGS. 6 and 7 is in the LP3 mode,
The same applies to the LP5 mode. However, the scanning angle is LP
There is a slight difference between 3 mode and LP5 mode. However, it is common that scanning is shifted by one track every two rotations or every three rotations. Therefore, both can read all data regardless of the tracking phase.

FIG. 8 shows the forward direction + N / 8 (7.5 / 4 = 1.
FIG. 8 is a diagram showing the state of head scanning during double-speed special reproduction, and shows the scanning locus of only −azimuth head 3a, as in FIGS. 6 and 7. Here, the solid line 34a is +
This is the case during N / 8 (1.875) speed reproduction, and the double-dashed line 31a indicates the case during + N / 2 (7.5) speed reproduction for reference. The + N / 2 (7.5) double speed reproduction is as described above. In the case of + N / 8 (1.875) double speed reproduction, the scanning is shifted by one track every four rotations in this way, and the portion that could not be read by the first scanning is always read by the scanning after four rotations. Become. Therefore, regardless of the tracking phase, all data can be read without fail by scanning every four rotations, and a reproduced image is constructed from the read data. -Direction and ± 1.5 /
The same applies to the case of 4 × to ± (N / 2−1) / 4 ×.

FIG. 9 shows the positive direction + N / 10 (7.5 / 5 =).
FIG. 9 is a diagram showing a state of head scanning at the time of special reproduction at 1.5) speed, and like FIG. 6, FIG. 7, and FIG. 8, shows a scanning locus of only −azimuth head 3a. Where the solid line 35
a is the case of + N / 10 (1.5) double speed reproduction, and 31a of the chain double-dashed line is the case of + N / 2 (7.5) double speed reproduction as a reference. The + N / 2 (7.5) double speed reproduction is as described above. + N / 10 (1.5)
In the case of the double speed reproduction, the scanning is shifted by one track every five rotations in this way, and the portion that cannot be read by the first scanning is surely read by the scanning after five rotations.
Therefore, no matter what the tracking phase is,
All data can be read without fail by scanning every rotation, and a reproduced image is constructed from the read data. -Direction and ± 1.5
The same applies to the case of / 5 × to ± (N / 2−1) / 5 ×.

FIG. 10 shows another head arrangement on the rotary drum 2. -Azimuth head 3a and + azimuth head 3b
Are adjacent to each other. With this head arrangement, two tracks of ± azimuth are recorded simultaneously in half a rotation, and as a result, it is possible to extend the multiples of the lengthening time, which was only possible with the head arrangement of FIG. 4, to all integers including even numbers. There is an effect that can be done. The rotation speed Rd of the rotary drum 2 is constant regardless of the recording mode, and changing the running speed Vt of the magnetic tape 1 according to the recording mode is the same as in the head arrangement of FIG.

FIG. 11 is a waveform diagram showing the timing of the recording signal in each recording mode. Similar to FIG.
(A) shows the rotation timing of the rotary drum 2. Here, the low level period is recorded by the magnetic heads 3a and 3b, and the high level period is recorded by the magnetic head 3b. (B) and (C) are waveforms of the recording signal in the SP mode.
Recording is performed by the magnetic heads 3a and 3b for each rotation only during a half rotation period. In (D) and (E), the time is twice as long as that in the SP mode, that is, in the recording mode (hereinafter referred to as LP2 mode) of the signal whose transmission rate of the received digital image signal is 1/2 of the standard. This is a waveform of a recording signal, and in this case, recording is performed every two rotations of the rotary drum 2. At this time, the traveling speed Vt of the magnetic tape 1 is set to 1/2 of the traveling speed in the SP mode. (F) and (G) are the 3
This is a waveform of a recording signal in a doubled time, that is, in the LP3 mode. In this case, recording is performed every three rotations of the rotary drum 2. At this time, the running speed Vt of the magnetic tape 1 is set to 1/3 of the running speed in the SP mode. And
Similarly, (H) and (I) are waveforms of recording signals in the long time mode (hereinafter, referred to as LP4 mode) which is four times as large as the SP mode. In this case, recording is performed every four rotations of the rotary drum 2. . The running speed Vt of the magnetic tape 1 is set to 1/4 of the running speed in the SP mode.

Table 2 shows the search speed at the time of special reproduction which is possible in this embodiment in each of the above recording modes.

[0044]

[Table 2]

As in Table 1, all the values here are 1 (reference) to the tape speed during recording and normal reproduction in SP mode.
It has shown with the absolute value. The SP mode is as described above. For the LP2 mode, ± 1.
Not only from 5x speed to ± N / 2x speed, but also 1/2 of that
It is possible to step from 1.5 / 2 times speed to ± N / 4 times speed. Similarly, for the LP4 mode,
Not only from 1.5x speed to ± N / 2x speed, but also 1/2 of that, ± 1.5 / 2x speed to ± N / 4x speed, 1/3 ± 1.5
/ 3x to ± N / 6x and 1/4 ± 1.5 / 4
From double speed to ± N / 8 double speed, each step is possible.

By the way, in the case of such a head arrangement,
In the case of ± 1.5 to ± N / 2 times speed, in which only speed control is used as tracking control and reading is performed once in two rotations, there is no problem with the recording pattern shown in the embodiment of FIG. However, when the phase is further controlled and all the data is read in one scan and the forward speed is M times and the reverse direction (M-2) times, the gap distance between the magnetic heads 3a and 3b becomes a problem.

FIG. 12 shows the head arrangement of FIG.
It is a figure which shows the recording pattern and head scanning by another Example of this invention which considered the gap distance of this magnetic head 3a and 3b. Here, (A) is at (+ M) speed, (B)
Is a case of-(M-2) times speed, and 13 is a recording area of special reproduction data. The feature of the present embodiment is that the length γ of the area 13 corresponds to the gap distance δ between the magnetic heads 3a and 3b, and the same data as the data recorded above the area 12 is recorded in this area 13. There is a point to be.

First, at the time of M-speed reproduction in the forward direction, the head 3a
And 3b trace the scanning loci 30a and 30b, respectively. Here, when the head 3a scans the area 11,
The head 3b is displaced downward by an inter-gap distance .delta.
Scan 2. Therefore, the upper part of the area 12 may not be read. Therefore, by recording the same data as the upper portion in the area 13, all the data can be reproduced. The same is true for (M-2) double speed reproduction in the opposite direction.

FIG. 13 shows still another head arrangement on the rotary drum 2. The −azimuth head 3a and the + azimuth head 3b are arranged adjacent to each other, and the −azimuth head 3c and the + azimuth head 3d are arranged adjacent to each other at a position opposite to each other by 180 degrees. The characteristic of this head arrangement is that it also corresponds to a recording mode (hereinafter referred to as HD mode) of a signal whose transmission rate of the received digital image signal is twice as high as the standard. The rotation speed Rd of the rotary drum 2 is constant regardless of the recording mode, and the running speed Vt of the magnetic tape 1 is changed according to the recording mode, as in the case of the head arrangement shown in FIGS. 4 and 10.

FIG. 14 is a waveform diagram showing the timing of the recording signal in each recording mode. 5 and 11
Similarly, (A) shows the rotation timing of the rotary drum 2. Here, the low level period is recorded by the magnetic heads 3a and 3b, and the high level period is recorded by the magnetic heads 3c and 3d.
Indicates the period recorded by. 11B and 11C are waveforms of recording signals in the same SP mode as in FIG. (D) and (E) are waveforms of the recording signal in the HD mode. In this case, the magnetic heads 3a and 3b and the magnetic heads 3c and 3d are alternately used for recording every half rotation of the rotary drum 2. At this time, the running speed Vt of the magnetic tape 1
Is set to twice the traveling speed in SP mode. The long time mode is the same as in FIG.

Table 3 shows each recording mode.
The search speed at the time of special reproduction which is possible in this embodiment is shown.

[0052]

[Table 3]

As in Tables 1 and 2, all the values here are SP.
Tape speed during recording and normal playback in mode 1
It is shown as an absolute value as the (reference). It goes without saying that tracking control using only speed control is sufficient. S
In the P mode, not only ± 1.5 times speed to ± N / 2 times speed, but also twice as much as ± 3 times speed to ± N times speed can be stepwise performed. For HD mode, ±
Stepping from 3x speed to ± Nx speed is possible. still,
Although not shown in Table 3, S
Similar to the P mode, not only the double speed shown in Table 2 but also a triple speed to ± N double speed can be performed stepwise.

FIG. 15 is a diagram showing head scanning in the head arrangement of FIG. (A) is forward direction + N (15)
At the time of double speed, (B) is the case of reverse speed-N (15) times the speed. In the tracking control using only the speed control, the special reproduction data recording area 13 is not particularly necessary, but as described above, it is necessary to support the high speed search with the phase control.

First, at the time of + N (15) double speed reproduction, the head 3
a and 3b, and heads 3c and 3d are scanning loci 36
Trace on a, 36b and 36c, 36d. At this time, the azimuth heads 3a and 3c are shifted by one track, and similarly to the case shown in FIG. 3, a portion which cannot be read by the head 3a is always readable by the head 3c. Therefore, no matter what the tracking phase is, all the data can be read without fail by scanning once.
The same applies to the scanning of + azimuth heads 3b and 3d. This is not limited to the N (15) times speed, and it is also possible to step from 3 times to N (15) times stepwise and in both the forward and reverse directions. Further, such scanning from ± 3 × speed to ± N × speed is the same in the HD mode, SP mode, and long time mode.

In addition, in the special reproduction of + 2 × M times speed and −2 × (M-2) times speed in which the phase control is applied, the inclination of the scanning locus of the head is + M times speed and − (M-2) times speed. Since it is doubled, there is a possibility that all the data cannot be read by one scan, and in this case, it may not be possible to deal with it.

FIG. 16 is a recording pattern diagram on the tape showing another embodiment of the recording system of the compressed moving image data according to the present invention. Here, reference numerals 15, 16 and 17 denote recording areas for special reproduction image data, and the same reference numerals as those in FIG. 1 indicate the same elements. This special reproduction image data recording area 15, 1
Similar to FIG. 1, the compressed moving image data for normal reproduction is recorded in the data recording areas other than 6 and 17, and the subcode data is recorded in the subcode recording area. The first feature of this embodiment is that a plurality of special reproduction image data recording areas are arranged only on one azimuth track (for example, −azimuth track) as shown in the figure. This eliminates the need to consider the gap distance between the heads in the head arrangement shown in FIGS. 10 to 13, and as a result, the special reproduction image data recording area 13 shown in FIG.
Since there is no need to take a redundant recording area like that, there is an effect that the image quality during special reproduction can be improved accordingly.

As in the embodiment of FIG. 1, the same special reproduction image data is recorded as one set of ± azimuth tracks, which is a feature of the present invention, with one set of ± azimuth tracks. As a result, it is possible to deal with all of the above-mentioned three types of head arrangements, and the simplest speed control is only the tracking control, which is ± 1.5 / J as shown in Tables 1, 2, and 3 above. (J is 1/2 or a natural number) Stepwise special reproduction from double speed to ± N / 2 / J double speed is possible.

The second feature of this embodiment is that, similar to the embodiment of FIG. 1, speed control is added to phase control as tracking control, and special reproduction image data recorded in these areas 15, 16 and 17 is recorded. In order to be able to read the subcode data recorded in the subcode recording area while reproducing at + M times speed and-(M-2) times speed, the special reproduction image data recording areas 15 and 16, 17 and the subcode recording area have the following relationship.

That is, the distance β between the center of the area 15 and the center of the sub-code recording area is represented by the above-mentioned equation 1, and the areas 16, 1
7 Distances β1 and β2 between the respective centers and the center of the sub-code recording area are expressed by the following mathematical expressions 3 and 4, respectively.

[0061]

## EQU3 ## β1≈L ÷ (M-1) × (k + 1)

[0062]

## EQU00004 ## .beta.2.apprxeq.L.div. (M-1) .times. (K-1) In consideration of track linearity and tracking error, .beta. Is set to L / 2 or less as in the embodiment of FIG. .

Further, the recording length α in the track direction of the area 15 is expressed by the above mathematical expression 2, and the recording lengths α1, α2 in the track direction of the areas 16 and 17 are expressed by the following mathematical expression 5 and mathematical expression 6, respectively. .

[0064]

[Formula 5] α1 <α

[0065]

Α2 = α1 Here, the reason why α1 and α2 are made smaller than α is that when the phase control is applied in the special reproduction recording area 15, considering the track linearity, the length that can be read in the areas 16 and 17 is This is because it decreases. Incidentally, the areas 15, 16, 17
It goes without saying that the recording lengths α, α1, α2 and the distances β, β1, β2 between them and the sub-code areas are defined by the number of blocks described above.

FIG. 17 is a diagram showing a print pattern and head scan according to still another embodiment of the present invention. here,
(A) is a positive direction H (H is an integer greater than or equal to N, for example,
H = 30) corresponding to the double speed, 50, 50 'and 50 "are the scanning loci of the magnetic head 3a at that time, 51 to 55, 5
Reference numerals 1u to 55u and 51l to 55l denote recording areas for the special reproduction data. Similarly, (B) is the case of the reverse H-speed, 60, 60 'and 60 "are the scanning loci of the magnetic head 3a at that time, 61 to 65, 61u.
.About.65u and 61l to 65l indicate recording areas of the special reproduction data. And these positive and reverse H
The arrangement pattern of the special reproduction data recording area corresponding to the double speed is repeated every 2 × H tracks.

First, in the SP mode and in the normal-direction H-speed reproduction, the azimuth head 3a traces along the scanning locus 50, the special reproduction data recorded in the areas 51 to 55 and the subcode in the subcode recording area. Data reading,
A reconstructed image is constructed from the obtained data. At this time, since the special reproduction data recording area is limited, track selection control is required in addition to speed control and phase control as tracking control. The phase control point is set at the center point of the region 54, as shown in the figure.

By the way, in this embodiment, in addition to the special reproduction data recording areas 51 to 55, the repeat areas 51u to 51u to
55u and 51l to 55l are provided. In consideration of track linearity and tracking error, the special reproduction data recorded is surely read not only in the SP mode but also in the H-speed reproduction in the LP2 mode and the LP4 mode, for example. Areas 51u to 55u record the same data as the lower portions of the areas 51 to 55, and 51l to 55l record the same data as the upper portions of the areas 51 to 55, respectively.

The scanning locus 50 'shown by the chain double-dashed line is LP2.
Mode, the scanning locus 50 "shown by the broken line is the LP4 mode,
The trace of -azimuth head 3a in each is shown. As described above, since the scanning locus is slightly deviated in each mode, the repeat areas 51u to 5u of the special reproduction data are obtained.
5u and 51l to 55l are provided. Incidentally, these special reproduction data recording areas 51 to 55, 51u to 55u,
Since all of 51 and 51l to 55l are provided on a single azimuth track, all the head arrangements shown in FIGS. 4, 10 and 13 can be supported.

The same applies to the case of the reverse H-speed in FIG. 17B.

As described above, in the present embodiment, when the track selection control is added to the speed control and the phase control as the tracking control, a high-speed search of H speed in the forward and reverse directions in absolute speed is realized regardless of the recording mode. it can.

Further, in this embodiment, the regions 11 ', 1
2'is provided so that the same data as the upper portion of each of the areas 11 and 12 is recorded here. As a result, not only SP mode but also LP2 mode and LP4 mode can be supported not only in SP mode, but also in forward direction M-fold speed and reverse direction (M-2) -fold speed reproduction, by adding phase control to speed control as tracking control. The recording area for special reproduction data can be shared regardless of the mode.

If the double speed number H at the time of this high-speed search is set such that the least common multiple thereof is the same as the least common multiple of the number N of repeated tracks in the areas 11 to 13, the special reproduction data generation processing is common. Therefore, the scale of the processing circuit can be reduced. For example, when N = 15, H = 15, 20 or 30 is preferable.

In the above embodiments, the sub-code recording area is arranged on the output side of each track. However, the present invention is not limited to this, and the sub-code recording area enters each track. It goes without saying that the format arranged on the side can also be supported.

[0075]

As described above, according to the present invention, a plurality of recording modes having different tape speeds can be dealt with, and ± 1.5 / J (J is 1/2
Or, it is possible to perform stepwise special reproduction from a (natural number) double speed to ± N / 2 / J double speed. Furthermore, if phase control is added, special reproduction at + M times speed and-(M-2) times medium speed is possible. Then, when track selection control is further added, special reproduction can be performed at a high speed of ± H times.
In addition, the subcode data recorded in the subcode recording area can be read while reproducing the special reproduction data. Moreover, various head arrangements can be accommodated, and special reproduction data and subcode data can be surely read even in compatible reproduction in an apparatus having different track linearity.

Further, since the patterns can be made common in a plurality of recording modes, the circuit structure becomes simple.

[Brief description of drawings]

FIG. 1 is a recording pattern diagram on a tape showing an embodiment of a recording method according to the present invention.

2 is a head trace pattern diagram showing a recording pattern on a tape according to the embodiment of FIG. 1 and an embodiment of a reproducing system according to the present invention. FIG.

3 is a waveform diagram showing a reproduction envelope in the embodiment of FIG.

FIG. 4 is a block diagram showing a configuration example of a recording apparatus that realizes a recording method according to the present invention.

5 is a waveform chart showing the timing of a recording signal in the embodiment of FIG.

6 is a head trace pattern diagram showing a recording pattern on a tape according to the embodiment of FIG. 1 and another embodiment of the reproducing system according to the present invention.

7 is a trace pattern diagram of a head showing a recording pattern on a tape according to the embodiment of FIG. 1 and a reproducing system according to still another embodiment of the present invention.

FIG. 8 is a trace pattern diagram of a head showing a recording pattern on a tape according to the embodiment of FIG. 1 and still another embodiment of a reproducing system according to the present invention.

9 is a trace pattern diagram of a head showing a recording pattern on a tape according to the embodiment of FIG. 1 and a reproducing system according to still another embodiment of the present invention.

FIG. 10 is a diagram showing another example of the head arrangement on the rotary drum.

11 is a waveform chart showing the timing of a recording signal in the head arrangement example of FIG.

FIG. 12 is a recording pattern on the tape and a trace pattern of the head showing another embodiment of the present invention corresponding to the head arrangement of FIG.

FIG. 13 is a diagram showing still another example of the head arrangement on the rotary drum.

14 is a waveform chart showing the timing of a recording signal in the example of the head arrangement of FIG.

FIG. 15 is a recording pattern on a tape and a trace pattern of a head showing another embodiment of the present invention corresponding to the head arrangement of FIG.

FIG. 16 is a recording pattern diagram on the tape showing another embodiment of the recording system according to the present invention.

FIG. 17 is a trace pattern diagram of a recording pattern on a tape and a head showing still another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Magnetic tape, 2 ... Rotating drum, 3a, 3b, 3c, 3d ... Magnetic head, 10a, 10b ... Recording track, 11, 11 ', 12, 12', 13, 15, 16, 1
7,51-55,51u-55u, 51l-55l, 6
1-56, 61u-65u, 61l-65l ... Special reproduction data recording area, 103 ... Priority data selection circuit, 104 ... Special reproduction data memory, 105 ... Main data memory, 106 ... Read control circuit, 107 ... Time division Multiplexing circuit, 108 ... Arrangement pattern control circuit, 109 ... Synchronous block forming circuit, 110 ... Recording modulation circuit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takao Arai 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Ltd.

Claims (20)

[Claims] 1. A selected one of a plurality of compressed moving image data having different transmission rates is sequentially recorded on tracks formed obliquely on a magnetic tape, and special reproduction is performed from the selected compressed moving image data. In the recording method of the compressed moving image data, in which a part of the main data necessary for the special reproduction data is extracted, and the special reproduction data recording area is provided in a specific portion of the track for recording. At least each track having the same azimuth angle is arranged, and n adjacent tracks having different azimuth angles are set as one set, and the same data is repeatedly recorded on each of N sets of tracks, and the value of the N is transmitted. A recording method for compressed moving image data, which is constant regardless of the rate. 2. The recording of compressed moving image data according to claim 1, wherein the recording areas for the special reproduction data are arranged on both positive and negative azimuth tracks and at only one position each. method. 3. The compressed moving image data according to claim 1, wherein a recording area for the special reproduction data is arranged only at one of positive or negative azimuth tracks and at a plurality of locations. Recording method. 4. The recording area for the trick play data according to claim 2, wherein M (M
Is an integer greater than or equal to N / 2) The compressed moving image data recording method is characterized in that the locus of the head corresponding to the M-fold speed is arranged on the locus for scanning the subcode recording area during double-speed reproduction. 5. The head locus corresponding to the M speed during sub-speed reproduction of M (M is an integer of N / 2 or more) normal reproduction in the recording areas of the plurality of special reproduction data according to claim 3. A recording method of compressed moving image data, characterized in that the code recording areas are arranged on the trajectories. 6. The second recording area according to claim 4, wherein a second recording area having a size corresponding to a gap distance between two magnetic heads mounted adjacent to each other is provided on one of the positive and negative azimuth tracks. A compression characterized by being provided adjacent to the entry side of the first recording area of the track and recording the same data as the data to be recorded on the exit side of the first recording area of the track in the second recording area. Recording method for moving image data. 7. The head according to any one of claims 1 to 6, which corresponds to a normal reproduction speed H (H is an integer equal to or greater than N) double speed mode, and a second special reproduction data corresponding to the H double speed. The recording method of compressed moving image data is characterized by recording in a third recording area provided along the locus. 8. The recording of compressed moving image data according to claim 7, wherein the third recording area is arranged on a locus of a head corresponding to the H double speed scanning a subcode recording area. method. 9. The method according to claim 7, wherein fourth and fifth recording areas are provided adjacent to an entrance side and an exit side of the third recording area, and the third recording area is provided with the third recording area.
The same data as the data to be recorded on the output side of the second recording area, and the same data as the data to be recorded on the input side of the third recording area in the fifth recording area. Recording method for moving image data. 10. The method for recording compressed moving image data according to claim 7, wherein the arrangement pattern is repeated at a cycle of the least common multiple of the H and the N. 11. One of a plurality of compressed moving image data having different transmission rates is selected and sequentially recorded on tracks formed in an oblique direction of a magnetic tape, and special reproduction is performed from the selected compressed moving image data. In the recording / reproducing method of the compressed moving image data, a part of the main data necessary for recording is reproduced by recording a specific recording area for the special reproduction data in a specific portion of the track for reproduction. An area is arranged at least for each track of the same azimuth angle of the track, and n adjacent tracks having different azimuth angles are set as one set, and the same data is repeatedly recorded on each of N sets of tracks, and the value of the N is set. Is constant regardless of the transmission rate, and the running speed of the magnetic tape is controlled to a running speed of ± 1.5 times to ± N / 2 times the normal playback speed, Recording and reproducing system of the compressed moving image data and recorded the special reproduction data, characterized in that play once in two scans for each said n number of adjacent tracks. 12. The recording of compressed moving image data according to claim 11, wherein the recording areas for the special reproduction data are arranged on both positive and negative azimuth tracks and at only one position each. Play method. 13. The compressed moving image data according to claim 11, wherein the recording area for the special reproduction data is arranged only at one of positive or negative azimuth tracks and at a plurality of locations. Playback recording method. 14. The recording area of the trick play data according to claim 12, wherein M (M
Is an integer of N / 2 or more) The locus of the head corresponding to the M speed during double speed reproduction is arranged on the locus for scanning the subcode recording area, and the running speed of the magnetic tape is + M times that of the normal reproduction, or- (M-2) times the traveling speed, and reproduces the special reproduction data recorded in the recording area and the subcode data recorded in the subcode recording area. Recording and playback method. 15. The head locus corresponding to the M speed during sub-speed reproduction of M (M is an integer not less than N / 2) normal reproduction in the recording areas of the plurality of special reproduction data according to claim 13. The code recording areas are respectively arranged on the scanning loci, and the running speed of the magnetic tape is controlled to a running speed of + M times or − (M−2) times of the normal reproduction, and the codes are recorded in the plurality of recording areas. A recording / reproducing system for compressed moving image data, which reproduces the special reproduction data and the subcode data recorded in the subcode recording area. 16. The second recording area according to claim 14, wherein the second recording area having a size corresponding to a gap distance between two magnetic heads mounted adjacent to each other is provided on one of the positive and negative azimuth tracks. Data that is provided adjacent to the entry side of the first recording area of the track and is the same as the data that is written on the exit side of the first recording area of the track is recorded in the second recording area. A recording / reproducing system for compressed moving image data, characterized in that the special reproduction data recorded in the second recording area is reproduced. 17. The head according to any one of claims 11 to 16, which corresponds to a normal reproduction speed H (H is an integer equal to or greater than N) double speed mode, and the second special reproduction data corresponding to the H double speed. Recording is performed in a third recording area provided along the locus of No. 1, and the running speed of the magnetic tape is controlled to a running speed of ± 1.5 times to ± N / 2 times that of normal reproduction, and the recording is performed. The special reproduction data recorded in the area is reproduced once by scanning twice for each of the n tracks, or the running speed of the magnetic tape is + M times or −M times that of normal reproduction.
The traveling speed of the magnetic tape is controlled to (M-2) times, and the special reproduction data recorded in the recording area is reproduced, or the traveling speed of the magnetic tape is increased by + H times or − during normal reproduction.
A recording / reproducing system for compressed moving image data, characterized in that the second special reproduction data recorded in the third recording area is reproduced by controlling the traveling speed to H times. 18. The recording medium according to claim 17, wherein the third recording area is arranged on a trajectory of a head corresponding to the H double speed scanning a sub-code recording area, and the third recording area is recorded in the third recording area. A recording / reproducing system for compressed moving image data, which reproduces the second special reproduction data and the subcode data recorded in the subcode recording area. 19. The recording medium according to claim 17, wherein fourth and fifth recording areas are provided adjacent to an entrance side and an exit side of the third recording area, and the third recording area is provided with the third recording area.
The same data as the data to be recorded on the output side of the third recording area is recorded in the fifth recording area, and the same data as the data to be recorded on the input side of the third recording area is recorded in the fifth recording area. The second recorded in the fourth and fifth recording areas
A method for recording and reproducing compressed moving image data, which reproduces the special reproduction data. 20. The recording / reproducing system for compressed moving image data according to claim 17, wherein the arrangement pattern is repeated at a cycle of the least common multiple of the H and the N.