JPH07235146A - Recording apparatus - Google Patents

Abstract

PURPOSE:To efficiently record data of various kinds by selecting a using error correction code in accordance with a combination of areas assigned to data. CONSTITUTION:Data recorded in a first area through a first. input part 21 and data recorded in a second area through a second input part 22 are input to an error correction encoder 24. The error correction encoder 24 selects error correction codes for respective input data in accordance with mode selection data, thereby to encode an error correction. Tone mode selection data itself is adapted to be recorded, making it possible to detect at a reproducing time in which mode the data is recorded. A recording signal-generator 25 adds a sync address, modulates or processes in the like manner thereby to generate a recording signal. A recording head 26 records the recording signal to a tape 27.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording device suitable for use in a digital video tape recorder or the like.

[0002]

2. Description of the Related Art A conventional recording device is a DDS (Digital Data
Storage) for example. The block diagram is shown in FIG. 10 and the track format is shown in FIG.
In FIG. 10, 11 is a data input unit, 12 is an error correction encoder, 13 is a recording signal generator, 14 is a recording head, and 15 is a tape.

In the recording apparatus configured as described above, the signal input to the data input section 11 is error-correction coded by the error-correction encoder 12. For data recorded in the main area (indicated as Main Area in the figure), the C3 code is (46,44), the C2 code is (32,26), and the C1 code is (32,28). Reed-S
The olomon code is used, and it is a code that is completed within the main area of 46 tracks as a whole. For the data recorded in the sub area, (32, 28) Reed-Solom
The on code is used. Sub-area (S in the figure
The data recorded in the ab Area) is information serving as an index of the data recorded in the main area. Thereafter, the recording signal generator 13 adds a sync address, modulates, etc., and records on the tape 15 using the recording head 14.

On the other hand, digital TV broadcasting, CATV,
A business for supplying a highly efficient coded video signal by digital transmission, such as a video service using a telephone line, has recently been studied. Then, along with this, it is expected that a recording device for recording such a highly efficient coded and digitally transmitted video signal will be required.

[0005]

However, in the recording apparatus configured as described above, the transfer rate of input data cannot exceed the data rate that can be recorded in the main area. When a signal such that the transfer rate of the input data exceeds the data rate that can be recorded in the main area is input and the data to be recorded in the main area is overflowed and recorded in the sub area, Since the correction capability of the error correction code used in the area is significantly lower than the correction capability of the error correction code used in the main area, there is no guarantee that the data recorded in the sub area can be reproduced correctly.

Further, there are various video signal transmission systems,
The transfer rate may be arbitrary. There is a problem that preparing a recording device corresponding to each transmission method is burdensome and complicated for general users.

The present invention is intended to solve the problems of the conventional recording apparatus.

[0008]

In order to solve the above problems, the recording apparatus of the present invention selects at least an error correction code used for recorded data in accordance with a combination of areas allocated to the data. The error correction coding means is provided.

[0009]

According to the present invention, the error correction code used for the recorded data is selected according to the combination of the areas allocated to the data, whereby the data can be recorded more efficiently than in the conventional case.

[0010]

EXAMPLES Examples of the recording apparatus of the present invention will be described below.
A description will be given with reference to the drawings.

A block diagram of a recording apparatus according to the first embodiment of the present invention is shown in FIG. 1 and its recording format is shown in FIG. 21 is a first input section, 22 is a second input section, 23 is a mode selection information input section, 24 is an error correction encoder, 25 is a recording signal generator, 26 is a recording head, and 27 is a tape. The operation of this recording apparatus will be described below with reference to FIG.

First, the data recorded in the first area through the first input unit 21 and the data recorded in the second area through the second input unit 22 are input to the error correction encoder 24. To be done. The error correction encoder 24 selects an error correction code for each of the input data according to the mode selection information input from the mode selection information input unit 23, and performs error correction coding. In addition, the mode selection information itself is also data to be recorded so that it is possible to determine which mode was used for recording. Recording signal generator
The recording head 26 records the recording signal on the tape 27 by performing a predetermined recording signal process such as addition of a sync address, modulation, etc., to generate a recording signal.

The format of the track formed on the tape is, as shown in FIG. 2, provided with a tracking and position information area, a first area, a second area, and a time code area from the entry side of the track. A buffer region is provided between each region. In the tracking and position information area, information for accurately scanning the track and information for determining the position of each area are recorded, and in the time code area, auxiliary data such as time code and cue information is recorded. To do.

For example, when the video data is allocated to the first area and the audio data is allocated to the second area and recorded, in the mode in which the areas are separately used, the error correction encoder 24 is provided with each of them. Error correction coding is independently performed for each data assigned to the area. By performing the processing independently in this way, it is possible to give each data desired error correction capability, and it is also possible to edit each area independently. In this mode, the error correction encoder 24 collects the data in an error correction code if the mode is a mode in which the areas are used together, for example, when a digital data string such as computer data is assigned to both areas. Make a change. If the processing is performed collectively in this way, there will be no problem because each area will not be edited independently, and grouping the areas will expand the range of interleaving and increase the error correction capability. Also effective.

According to the above configuration, the error correction code to be used is selected according to the area allocation method used for recording,
A system capable of recording various data becomes possible.

FIG. 3 shows an example of the configuration of the error correction encoder 24. In FIG. 3, 31a and 31b are first switches, 32 is a second switch, 33 is a C3 encoder, 34 is a first C2 encoder, 35 is a second C2 encoder, and 36. Is a third switch, 37 is a C1 encoder, and 38 is a switching controller. The operation will be described based on (FIG. 3). A data flow diagram is shown in (a) and (b) of FIG.

First, the first switches 31a and 31b are
When the data recorded in the area 2 and the data recorded in the second area are collectively subjected to error correction coding, they are connected to the terminal 1 side, and the data recorded in the first area and the data recorded in the second area are connected. When the error correction coding is performed by dividing the data to be recorded in (1), it is connected to the terminal 2 side and controlled by the mode selection information. The first switch 31a
However, when it is connected to the terminal 2 side, its output is assumed to be a fixed value such as all zeros.

Data to be recorded in the first area and data to be recorded in the second area are input to the C3 encoder 33 while being switched by the second switch 32. Then, encoding is performed using the error correction code selected based on the mode selection information. If only the code length is changed and the error correction code using the same generator polynomial is used without changing the number of check symbols, the circuit configuration is simple and the data recorded by the present invention is reproduced. At times, the circuit configuration of the error correction decoder becomes simple. Then, the data recorded in the first area and the check symbol of the C3 code are transferred to the first C2 encoder.
The data output to 34 and recorded in the second area is recorded in the second C
2 Output to the encoder 35. The first C2 encoder 34 and the second
C2 encoder 35 performs error correction encoding on the respective input data. In the C1 encoder 37, the data recorded in the first area outputted from the first C2 encoder 34, the check symbol of the C3 code, the check symbol of the first C2 code, and the second C2 The data recorded in the second area and output from the encoder 35 and the check symbol of the second C2 code are input while being switched by the third switch 36. The C1 encoder 37 performs error correction coding of the C1 code. The switching controller 38 controls switching between the second switch 32 and the third switch 36.

Here, as an example of each error correction code, C
(85,77) Reed-Solomon code as the first code, the first C2
(149,138) Reed-Solomon code as code, second C2
A (14,9) Reed-Solomon code may be used as the code, and a (147,136) or (138,127) Reed-Solomon code may be used as the C3 code.

According to the above configuration, a mode for recording data using the first area and the second area, and a mode for recording data using only the first area and making the second area optional In the second area, it is possible to construct a flexible system capable of selecting a mode in which later edit recording is possible.

Although the error correction encoder 24 uses different C2 codes in the first area and the second area, the same effect can be obtained even if the same error correction code is used. Although the same C1 code is used in the first area and the second area, the same effect can be obtained by using different error correction codes depending on the area.

FIG. 5 shows another structural example of the error correction encoder 24. In FIG. 5, 31a and 31b are first switches, 32 is a second switch, 43 is a C2 encoder, 36 is a third switch, 47 is a C1 encoder, and 48 is a switching controller. . The operation will be described based on (FIG. 5). Also,
A data flow diagram is shown in (a) and (b) of (FIG. 6).

First, the first switches 31a and 31b are
When the data recorded in the area 2 and the data recorded in the second area are collectively subjected to error correction coding, they are connected to the terminal 1 side, and the data recorded in the first area and the data recorded in the second area are connected. When the error correction coding is performed by dividing the data to be recorded in (1), it is connected to the terminal 2 side and controlled by the mode selection information. The first switch 31a
However, when it is connected to the terminal 2 side, its output is assumed to be a fixed value such as all zeros.

The data recorded in the first area and the data recorded in the second area are input to the C2 encoder 43 while being switched by the second switch 32. Then, encoding is performed using the error correction code selected based on the mode selection information. If only the code length is changed and the error correction code using the same generator polynomial is used without changing the number of check symbols, the circuit configuration is simple and the data recorded by the present invention is reproduced. At times, the circuit configuration of the error correction decoder becomes simple. Then, the data recorded in the first area and the check symbol of the C2 code are output to the terminal x side of the third switch 36, and the data recorded in the second area is recorded in the first area.
Output to the terminal 1 side of the switch 31b. C1 encoder 37
Includes data recorded in the first area output from the C2 encoder 43, a check symbol of the C2 code, and a first switch.
The data output from 31b and recorded in the second area is input while being switched by the third switch 36.
The C1 encoder 37 performs error correction coding of the C1 code. The switching controller 48 is the second switch 32 and the third switch.
Control 36 switching.

Here, as an example of each error correction code, C
(85, 77) Reed-Solomon code may be used as one code, and (163, 152) or (149, 138) Reed-Solomon code may be used as C2 code.

According to the above-mentioned structure, the mode in which the data is recorded using the first area and the second area, and the mode in which the data is recorded using only the first area and the second area is made optional. In the second area, it is possible to construct a flexible system capable of selecting a mode in which later edit recording is possible.

In the error correction encoder 24, the same C1 code is used in the first area and the second area, but the same effect can be obtained even if different error correction codes are used in different areas.

Such a system can be used to record digitally transmitted video signals, where various types of signals are expected to be present. And as optional data,
The audio signal to be after-recorded and the data prepared for special playback can be given.

It is also possible to use modes other than the above modes. For example, the above two types of error correction encoders
If a configuration combining 24 is used, (a) of (FIG. 7),
As shown in (b), C3 is added to the data recorded in each area.
A mode in which both codes and C2 codes are collectively subjected to error correction coding, and C3 codes and C2 codes are used only for data recorded in the first area.
A mode that performs error correction coding of the code can be used. Alternatively, as shown in (FIG. 8), when the data recorded in the first area is excessive by the amount corresponding to the check symbol of the C3 code, the mode in which the C3 coding is not performed can be used. .

Although the structure in this embodiment is a recording device, it may be a recording part of a recording / reproducing device.
Although 24 is a recording head, it may be a recording / reproducing head. Further, although the track is composed of four areas and the buffer area between them, the present invention can be applied regardless of the number of areas per track or the order of the areas in the track.

Further, in this embodiment, it is assumed that the track is composed of four areas and the buffer areas between them, and the error correction code can be selected by the combination of the areas.
The same effect can be obtained by providing a small area obtained by further dividing each area and selecting an error correction code by combining the small areas. As shown in FIG. 9, the first area of the track format shown in FIG. 2 is divided into a small area 1a and a small area 1b, and an error correction code is obtained by combining the small area 1a, the small area 1b and the second area. Can be selected. For example, the error correction encoder of FIGS. 3 and 5 processes the data in the first area and the data in the second area separately. This is the data of the small area 1b,
The data in the small area 1b and the data in the second area can be separately processed. The method of dividing the small area is not limited to that described here, and any area may be divided. Also, the number of small areas may be an arbitrary number for each area.

In the configuration of the present embodiment, the first input section 21 and the second input section 22 are separated, but a single input section may also be used. The data to be recorded is recorded in two areas, the first area and the second area, and two types of modes can be selected. However, the number of areas and the number of modes are expanded to three or more. It is possible to do so with a similar configuration.

In this embodiment, one track is divided into two areas, a first area and a second area.
The present invention can be applied to a case where a track is divided into areas and a case where these areas are combined.

In the present invention, the range of error correction code (configuration of product code, selection of each code) and interleaving is arbitrary.

In the present embodiment, the mode selection information is recorded on the tape at the same time as the data. However, when there is an auxiliary storage medium (memory or magnetic tape) attached to the cassette containing the tape, It is also possible to store the mode selection information in the auxiliary storage medium. By doing so, it is possible to correctly obtain the identification information of the system of the recorded transmission signal before starting the reproducing operation.

[0036]

As described above, according to the recording apparatus of the present invention, various data can be efficiently recorded by selecting and recording the error correction code to be used according to the area allocation method used for recording. A flexible system can be constructed, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram of a recording apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a track format of the recording device according to the first embodiment of the present invention.

FIG. 3 is a block diagram of an example of the error correction encoder 24 in the first embodiment of the present invention.

FIG. 4 is a data flow diagram by the error correction encoder of FIG.

FIG. 5 is a block diagram of an example of the error correction encoder 24 in the first embodiment of the present invention.

FIG. 6 is a data flow diagram by the error correction encoder of FIG.

FIG. 7 is a data flow diagram showing another example of data flow.

FIG. 8 is a data flow diagram showing another example of data flow.

FIG. 9 is an explanatory diagram of other track formats.

FIG. 10 is a block diagram of a conventional recording device.

FIG. 11 is an explanatory diagram of a track format of a conventional recording device.

[Explanation of symbols]

 21 First Input Section 22 Second Input Section 23 Mode Selection Information Input Section 24 Error Correction Encoder 25 Recording Signal Generator 26 Recording Head 27 Tape

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location G11B 20/18 J 9074-5D N28 K 9074-5D N28 20/12 103 9295-5D

Claims (10)

[Claims] 1. A recording apparatus comprising at least error correction coding means for selecting an error correction code to be used for recorded data according to a combination of recording areas assigned to the data. 2. The recording apparatus according to claim 1, wherein the error correction coding means selects a code length of the error correction code. 3. The recording apparatus according to claim 1, wherein the error correction coding means selects the code length of the outer code when the double product code is used. 4. The recording area comprises a first recording area and a second recording area, and the error correction coding means has a code length a1 and the number of information symbols (a1−) for the data recorded in the first recording area. b1)
Outer coding using the second error correction code that is the above, and inner coding using the first error correction code that is the code length c and the number of information symbols (cd), and For the data recorded in the recording area, the code length c and the number of information symbols (c
-D) A first mode for performing encoding using the first error correction code, data recorded in the first recording area, and data recorded in the second recording area are summarized. Outer coding using a second 'error correction code having a code length a2 and the number of information symbols (a2-b2), and the data recorded in the first recording area and the second' error correction With respect to the data recorded in the second recording area, the check code of the code is subjected to inner coding using the first error correction code having the code length c and the number of information symbols (cd). 4. The recording according to claim 3, wherein any one of the second modes for performing the inner coding with the code length c and the number of information symbols (c-d) using the first error correction code is selected. apparatus. 5. The recording apparatus according to claim 4, wherein the error correction coding means also records selection information indicating which of the first mode and the second mode is selected. 6. The selection information indicating which one of the first mode and the second mode is selected is stored in an auxiliary storage medium attached to a cassette containing a medium for recording data. The recording device according to claim 4. 7. The recording apparatus according to claim 2, wherein the error correction coding means selects the code length of the outermost error correction code when the triple product code is used. 8. The recording area comprises a first recording area and a second recording area, and the error correction coding means has a code length a1 and the number of information symbols (a1−) for the data recorded in the first recording area. b1)
Outermost coding using the third error correction code that is the following, and code length c1, outer coding using the second error correction code that is the number of information symbols (c1-d1), and code length e, information Inner coding is performed using the first error correction code, which is the number of symbols (ef), and the code length c2 and the number of information symbols (c2-d2) for the data recorded in the second recording area. ) Is the second '
Outer coding using the error correction code of No. 1 and inner coding using the first error correction code of the code length e and the number of information symbols (e−f), and the first mode Outermost coding using the data recorded in the recording area and the data recorded in the second recording area together with the code length a2 and the 3'th error correction code having the number of information symbols (a2-b2) The
The second error correction code having the code length c1 and the number of information symbols (c1-d1) is used for the data recorded in the first recording area and the check symbol of the third 'error correction code. Outer coding and inner coding using the first error correction code having the code length e and the number of information symbols (ef) are performed, and the data is coded to the data recorded in the second recording area. Long c2,
Outer coding using the second 'error correction code, which is the number of information symbols (c2-d2), the code length e, and the number of information symbols (e-
8. The recording apparatus according to claim 7, wherein any one of the second modes of f) in which inner coding is performed using the first error correction code is selected. 9. The recording apparatus according to claim 8, wherein the error correction coding means also records selection information indicating which of the first mode and the second mode is selected. 10. The selection information indicating which one of the first mode and the second mode is selected is stored in an auxiliary storage medium attached to a cassette containing a medium for recording data. The recording device according to claim 8.