JP2001028102A - Recording and/or reproducing device for tape-like recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable recording/reproduction real time for digital data inputted/ outputted at a low speed, without imparting a load to a recording medium, by recording and/or reproducing for the digital data for an area of a prescribed length within a track. SOLUTION: A data transfer speed N is slower than or the same as recording/reproducing speed M for a magnetic tape 2 of the recording/reproducing device of this magnetic tape. Data quantity is detected for the digital data inputted in an input processing part, with the transfer speed N detected. On the basis of transfer speed information supplied, the data quantity recording in one track is controlled so that the digital data is recorded in the area of L×N/M length in the track. In this case, L is the length of one track of the magnetic tape 2; the data is recorded only in the area of L×N/M length in the track of the magnetic tape 2, leaving other areas unrecorded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording and / or reproducing apparatus for a tape-shaped recording medium for recording and reproducing data using a rotating drum.

[0002]

2. Description of the Related Art Conventionally, there has been known a digital tape recorder which records a bit stream of AV data broadcasted by digital satellite broadcasting or a bit stream of digital data transmitted via a network on a tape medium. Since the digital tape recorder uses a tape medium, it can record a large amount of digital data.

In such a digital tape recorder,
Since digital data is handled, there is no need to match the signal transfer speed from the outside to the device with the recording speed on the tape medium, unlike a conventional analog video tape recorder. Therefore, if the recording rate of data to the tape media is faster than the transfer rate of external data, the digital tape recorder must perform real-time recording by temporarily storing input digital data in a buffer or the like. Can be.

[0004]

When the recording rate of data to the tape medium and the transfer rate of the data are different from each other and the transfer rates of the two are different, the digital tape recorder determines the difference in the speed by some method. Must be absorbed. In such a case, when the recording rate of data to a tape medium is M and the transfer rate of data from a network or the like is N (N <M), for example,
The recording / reproducing is performed by intermittently operating the digital tape recorder at a timing of N / M, or the recording / reproducing is performed each time the drum rotates M / N with the tape medium traveling speed of N / M. It is common to absorb speed differences.

[0005] However, when the digital tape recorder is operated intermittently at the timing of N / M to perform recording and reproduction, the transient movement may damage the tape medium. Further, even if the interval of the intermittent operation is widened by increasing the capacity of the buffer, the cost is increased.

Further, the running speed of the tape medium is set to N / M.
If recording and reproduction are performed every time the drum rotates M / N, the recording pattern on the tape medium changes depending on the data transfer speed, which is the same as performing a simple time shift.

[0007] The present invention has been made in view of such circumstances, and a tape-shaped recording medium for recording and reproducing digital data input / output at a low speed without imposing a load on the tape-shaped recording medium. It is an object of the present invention to provide a recording and / or reproducing apparatus.

[0008]

In order to solve the above-mentioned problems, a recording and / or reproducing apparatus for a tape-shaped recording medium comprises:
By using input / output means for inputting and / or outputting digital data at a transfer speed N and a rotating drum provided with a magnetic head, a predetermined length of one track is determined for a tape-shaped recording medium having a length L. Recording / reproducing means for rotationally recording and / or rotating / reproducing the digital data at a recording / reproducing transfer rate M (M ≧ N), wherein the recording / reproducing means has a length of L × N / M within a track. On the other hand, the digital data is recorded and / or reproduced.

[0009] This recording and / or reproducing apparatus for a tape-shaped recording medium is characterized in that digital data is recorded and / or reproduced in a range of L × N / M in a track. Here, L is the track length of the tape-shaped recording medium, N is the transfer speed of digital data input / output to / from the outside, and M is the recording / reproducing transfer speed for the tape-shaped recording medium.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a magnetic tape recording / reproducing apparatus to which the present invention is applied will be described as an embodiment of the present invention with reference to the drawings.

FIG. 1 is a block diagram of a magnetic tape recording / reproducing apparatus to which the present invention is applied.

A magnetic tape recording / reproducing apparatus 1 shown in FIG.
Is a device for recording and reproducing digital data on a magnetic tape 2 which is a tape-shaped recording medium. The magnetic tape recording / reproducing apparatus 1 includes an input terminal 3, an output terminal 4, an input buffer 5, an output buffer 6, an input data processing unit 7, an output data processing unit 8, a recording signal processing unit 9, , A reproduction signal processing unit 10 and a transfer speed determination unit 11. The magnetic tape recording / reproducing apparatus 1 includes a rotary drum 12 provided with a magnetic head, a capstan 13 for running the magnetic tape 2, a drum driver 14 for driving the rotary drum 12, and a drive for driving the capstan 13. And a mechanical controller 16.

The input terminal 3 and the output terminal 4 are connected to, for example, a set-top box for receiving digital satellite broadcasts, and a digital satellite broadcast bit stream is input and output as digital data. The digital data input to and output from the input terminal 3 and the output terminal 4 are not limited to bit streams from satellite broadcasting, but may be any digital data.

The input buffer 5 temporarily stores digital data input at a predetermined data transfer rate via the input terminal 3.

The input data processing unit 7 performs processing such as addition of system information such as additional information for recording and reproduction, address information, and addition of an error correction code to the digital data stored in the input buffer 5. .

The recording signal processing unit 9 includes an input data processing unit 7
A modulation process is performed on the data processed in step (1), and a process of dividing the data into data amounts recordable in one track on the magnetic tape 2 is performed. The recording signal processing section 9 drives a magnetic head provided on the rotating drum 12 based on the generated data to record digital data on the magnetic tape 2.

The reproduction signal processing unit 10 detects a reproduction signal from a magnetic head provided on the rotating drum 12 and reproduces digital data recorded on the magnetic tape 2. The reproduction signal processing unit 10 performs demodulation processing and the like on the reproduction signal, and performs processing for synthesizing data separated for each track.

The output data processing unit 8 includes the reproduction signal processing unit 1
It detects additional information and the like from the data processed in 0, and performs data conversion processing and the like so that the data format conforms to the bit stream to be output.

The output buffer 6 temporarily stores the data processed by the output data processing unit 8, and outputs digital data from the output terminal 4 at a predetermined data transfer rate.

The transfer rate determining section 11 detects the data transfer rate of the digital data input to the input data processing section 7. The transfer speed determining unit 11 supplies information on the data transfer speed of the detected input digital data to the recording signal processing unit 9. The recording signal processing unit 9 performs signal processing based on the supplied information on the data transfer speed. Further, the transfer speed determining unit 11 obtains a data transfer speed of digital data output from the reproduction signal reproduced by the reproduction signal processing unit 10. The transfer speed determining unit 11 supplies information on the obtained data transfer speed of the digital data to be output to the output data processing unit 8. The output data processing unit 8 outputs digital data according to the supplied data transfer speed information.

The rotary drum 12 is provided with two magnetic heads, for example, at positions 180 degrees opposite each other with respect to the center of rotation. The rotating drum 12 includes a drum driver 14
Is driven to rotate. The rotation speed of the rotary drum 12 is represented by R. The recording and reproducing heads of the two magnetic heads are controlled to be switched by the recording signal processing unit 9 or the reproduction signal processing unit 10 to record or reproduce digital data.

The capstan 13 causes the magnetic tape 2 to run at a predetermined speed by sandwiching the magnetic tape 2 with, for example, a pinch roller (not shown). Capstan 13
Is driven to rotate by a capstan driver 15.
The traveling speed of the magnetic tape 2 traveling by the capstan 13 is represented by S.

The mechanical controller 16 includes the rotating drum 12
A control signal is supplied to the drum driver 14 based on the FG signal and the PG signal indicating the rotation speed and the like from the
The servo control of the rotation speed and the position of the magnetic head is performed. The mechanical controller 16 supplies a control signal to the capstan driver 15 based on the FG signal indicating the rotation speed from the capstan 13 to control the running speed of the magnetic tape 2.

The above-described magnetic tape recording / reproducing apparatus 1
Then, the rotating drum 12 rotates at the rotation speed R, and the magnetic tape 2 runs at the speed S. As a result, the magnetic tape recording / reproducing apparatus 1 records or reproduces digital data on the magnetic tape 2 at a recording / reproducing speed M.

Next, the recording or reproducing operation of the magnetic tape recording and reproducing apparatus 1 when the data transfer rate of the digital data input to the input terminal 3 or the digital data output from the output terminal 4 is N will be described. I do. It is assumed that the data transfer speed N is lower than or the same as the recording / reproducing speed M of the recording / reproducing apparatus 1 for the magnetic tape with respect to the magnetic tape 2.

First, at the time of recording, the transfer speed determining unit 11
Detects the amount of digital data input to the input data processing unit 7, and detects the transfer speed (N) of the digital data. The transfer speed determining unit 11 supplies information on the detected transfer speed of the digital data to the recording signal processing unit 9. The recording signal processing unit 9 performs data recording on one track so that digital data is recorded in the L × N / M length range in the track based on the supplied transfer speed information. Control the amount. Here, L is the length of one track of the magnetic tape 2. Then, the recording signal processing unit 9 supplies a recording signal whose data amount is controlled to the magnetic head while switching the magnetic head in synchronization with the rotation of the rotary drum 12, and records digital data on the magnetic tape 2. At this time, the rotating drum 12 rotates at a constant rotation speed R, and the magnetic tape 2 also runs at a constant speed S. Therefore, on the magnetic tape 2, as shown in FIG. 2, data is recorded only in the area of L × N / M length in the track, and the other parts are unrecorded areas.

On the other hand, at the time of reproduction, the reproduction signal processing unit 10
However, while switching the magnetic head in synchronization with the rotation of the rotary drum 12, a reproduction signal is detected from the magnetic head and the digital data recorded on the magnetic tape 2 is reproduced.
At this time, the rotating drum 12 rotates at a constant rotation speed R, and the magnetic tape 2 also runs at a constant speed S. The transfer speed determining unit 11 detects the length of a portion where data in the track is recorded from the reproduced signal reproduced by the reproduced signal processing unit 10, and determines the transfer speed of the digital data to be output from the length of the portion. calculate. That is, since the length of the portion of the track where the data is recorded is L × N / M, the transfer speed N of the digital data is obtained by performing an inverse calculation. The transfer speed determining unit 11 supplies the obtained transfer speed N to the output data processing unit 8. The output data processing unit 8
Data is output based on the supplied transfer speed N.

The magnetic tape recording / reproducing apparatus 1 to which the present invention is applied performs the above-described processing without intermittently operating the rotating drum 12 and the magnetic tape 2, thereby improving the digital data input / output speed. Thus, the difference from the recording speed on the magnetic tape 2 can be absorbed. Therefore, the recording / reproducing apparatus 1 for the magnetic tape does not increase the input / output buffer amount and does not impose a load on the magnetic tape 2,
Digital data can be recorded and reproduced in real time.

In the recording / reproducing apparatus 1 for a magnetic tape,
When a plurality of input / output terminals are provided and digital data of a plurality of channels is input / output, the total of the data transfer speeds of all the channels is Nx (Nx ≦ M), and the length of L × Nx / M in the track The amount of data to be recorded in one track of the magnetic tape 2 is controlled so that data is recorded only in the area of. As a result, even when a plurality of digital data are input, real-time recording can be performed without intermittently operating the rotating drum 12 and the magnetic tape 2, and data is reproduced from each channel at the same transfer speed as at the time of recording. can do.

The L (1) in the track of the magnetic tape 2
The area having a length of (−N / M) is an unrecorded area in which no data is recorded.
Then, digital data may be additionally recorded in this unrecorded area later.

The previously recorded digital data may be pre-read and reproduced, the pre-read and reproduced digital data may be combined with the digital data to be additionally recorded, and the track may be overwritten. Thus, track continuity can be ensured, and a margin between blocks in one track can be eliminated. In addition, by setting the value of N / M to an integer, when the pre-read and reproduced digital data is combined with the digital data to be additionally recorded and the digital data is additionally recorded in the unrecorded area, there is no waste in the track. Area is eliminated.

In the magnetic tape recording and reproducing apparatus 1,
By setting a predetermined unit time and recording digital data on the magnetic tape 2 in units of this unit time,
Fragmentation can be reduced.

[0033]

According to the recording and / or reproducing apparatus for a tape-shaped recording medium according to the present invention, recording and / or reproducing of digital data can be performed for a range of L × N / M length in a track. Features. Here, L is the track length of the tape-shaped recording medium, N is the transfer speed of digital data input / output to / from the outside, and M is the recording / reproducing transfer speed for the tape-shaped recording medium. Thereby, in the recording and / or reproducing apparatus for a tape-shaped recording medium according to the present invention,
Digital data input / output at low speed can be recorded / reproduced in real time without imposing a load on the tape-shaped recording medium.

[Brief description of the drawings]

FIG. 1 is a block diagram of a magnetic tape recording / reproducing apparatus to which the present invention is applied.

FIG. 2 is a diagram illustrating a magnetic tape on which digital data is recorded by the magnetic tape recording / reproducing apparatus.

[Explanation of symbols]

1 magnetic tape recording / reproducing device, 2 magnetic tape, 3
Input terminal, 4 output terminal, 5 input buffer, 6 output buffer, 7 input data processing section, 8 output data processing section, 9 recording signal processing section, 10 reproduction signal processing section, 11
Transfer speed discriminator, 12 rotating drum, 13 capstan, 14 drum driver, 15 capstan driver, 16 mechanical controller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toyomi Fujino 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F-term (reference) 5D031 AA03 EE07 EE08 HH01

Claims (4)

[Claims] An input / output means for inputting and / or outputting digital data at a transfer speed N, and a rotating drum provided with a magnetic head are used to record one track on a tape-shaped recording medium having a length of L. Recording / reproducing means for rotatingly recording and / or rotating / reproducing the digital data at a predetermined recording / reproducing transfer rate M (M ≧ N), wherein the recording / reproducing means comprises L × N / M Recording and / or reproduction of the digital data over a range of length, recording and / or recording on a tape-shaped recording medium;
Or a playback device. 2. The input / output means according to claim 1, wherein a sum of transfer speeds is N.
x (Nx ≦ M) is input and / or output, and the recording / reproducing means records and / or reproduces digital data in a range of L × Nx / M in a track. The recording and / or reproducing apparatus for a tape-shaped recording medium according to claim 1, wherein the recording and / or reproducing apparatus is performed. 3. The recording and / or reproducing apparatus according to claim 1, wherein said recording / reproducing means additionally records said digital data on an unrecorded portion of each track. 4. The recording / reproducing means pre-reads the digital data recorded in each track when performing additional recording of digital data, and combines the digital data to be additionally recorded with the pre-read digital data, and synthesizes. 2. The recording and / or reproducing apparatus for a tape-shaped recording medium according to claim 1, wherein the read digital data is overwritten on a pre-read track.