JPS63112873A - Protecting system for digital data - Google Patents

Abstract

PURPOSE:To make it impossible to reproduce a data by other person than the person concerned, and to protect a data by allowing a sink code to have an identification function. CONSTITUTION:An input data 1 is supplied to the error correcting code adding part 2 of a recording system, a recording data 8 is generated by using a sink 5 consisting of a code which is known to only the person concerned, from a digital switch 20, and this data 8 is recorded in a recording medium 9. When other person than the person concerned desires to reproduce a data and inputs it to a reproducing system, a sync contained in a data 10 which is read out of the recording medium 9 by the reproducing system becomes a sync which is known to only the person concerned, and on the other hand, to a code detecting part 12, the sync of a standard code format is only supplied from a code generating part. Accordingly, a code detection is executed by the standard sync, and from the code detecting part 12, all coincidence information 14 is detected. In such a way, reproduction of a data by an error correcting part 13 becomes impossible, and the data is protected.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a digital data processing method equipped with an error correction function, and is particularly suitable for data protection when reproducing data from a recording medium. Regarding the protection method.

[Summary of the invention]

When processing digital data, a method is known in which this data is divided into predetermined lengths, a parity code, etc. for error correction is added to each divided data, and error correction is performed for each of these divided data. It is being

By the way, in such a method, in order to identify the above-mentioned division position, special data called, for example, a sync code is inserted.

Therefore, in the present invention, this sync code is provided with a password function so that data protection can be easily obtained.

[Conventional technology]

Generally, when recording and reproducing digital data, continuous or single bit errors may occur due to defects in the recording medium used or noise when reading the recorded data. Error correction methods are commonly applied.

By the way, as an error correction method in such a case,
Conventionally, a method has been commonly used in which a series of digital data is sequentially divided into predetermined lengths and an error correction code such as a parity code is added to each divided data. To explain this with reference to FIG. 2, first, in the recording system, input data 1 is supplied to the error correction code addition section 2, where the input data 1 is sequentially divided into word units to form error correction blocks. An error correction code is added to each error correction block to form a data structure as shown in FIG. 3(a).

However, since the error correction code added at this time changes depending on the content of the data, it is not possible to determine the delimitation of the data as it is, and such data is directly transferred to the second
If it is recorded on the recording medium 9 as the recorded data 8 in the figure,
The reproduction system cannot distinguish between input data and error correction code,
Not only is it impossible to correct errors, but if this continues, even the substance of the input data will become unclear.

Therefore, as shown in FIG. 3(b), a code that is always constant and does not change is inserted into the delimiter at the beginning of each error correction block, and by detecting this code, the error correction code and subsequent input A method of distinguishing between data and data is applied. This method will be further explained with reference to FIG. 2. First, in the recording system, a predetermined space is provided in advance at the starting point of each error correction block. Then, each time this space is cursed, the switch 6 in the code addition section 7 is switched to the code signal input 5, thereby inserting a predetermined code from the code generation section 4,
As a result, the recorded data 8 on the medium 9 is as shown in FIG. 3(b).
The data should look like this.

On the other hand, in the reproduction system, as shown in FIG. 12, and by detecting a match, the starting point of each error correction block is recognized, and -number information 14 is generated. Then, the error correction unit 13 distinguishes the read data 10 into input data and an error correction code such as a parity code based on this matching information 14, performs error correction based on this, and outputs data that faithfully reproduces the input data 1. The goal is to get 15.

Note that the above-described code used for differentiation is generally called a sync code (also called an index, index marker, etc.).

By the way, in such conventional digital data processing systems, no particular consideration was given to data protection.

[Problem that the invention seeks to solve]

In recent years, the digitization of audio and video has progressed, and as a result, digital data recording/playback systems (digital VTRs, digital audio recorders, digital audio discs, data recorders, etc.) have become widespread.

For this reason, anyone can easily obtain recorded data by obtaining a recording medium (videotape, audiotape, diskette, etc.), and furthermore, video and audio differ from analog signals. Since there is no deterioration of video and audio during dubbing, it is possible to copy any number of copies of the same level as the source data.

While this is an advantage, it also creates an environment where problems such as copyright f61 infringement are likely to occur. In particular, in the future, it is expected that digital recording/playback systems will increasingly handle private data, such as patient examination data, registered data of a person's address and telephone number, and corporate strategy data. At this time, solving the above problems becomes important.

The present invention has been made in view of these points, and its purpose is to easily protect data in a data processing system that employs an error correction method, and to The goal is to provide a data protection method.

[Means for solving problems]

In order to achieve the above object, the present invention is such that the sync code used in the error correction system has a password function.3 [Operation] In the above error correction system, the sync code is It is essential to detect this sync code, and unless this sync code is known, it will be impossible to distinguish between data and an error correction code, and data reproduction will be impossible.

Therefore, if this sync code is not a general code but a special code that only the person concerned can understand, and the sync code is given a password function, no one other than the person concerned will be able to reproduce the data. You can make it impossible and protect your data.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The digital data protection system according to the present invention will be explained in detail below using illustrated embodiments.

FIG. 1 shows an embodiment of the present invention. In the figure, 16 is a sync code in the reproduction system (hereinafter simply referred to as sync), 20
．． 21 is a digital switch, and the rest is the same as the conventional example shown in FIG.

Therefore, as is clear from the comparison of FIGS. 1 and 2, the difference between this embodiment and the conventional example shown in FIG. 2 is that the sync 5 in the recording system and the sync 16 in the reproduction system are In contrast to the conventional example, which is a general type code consisting of a standard combination that is fixedly generated from the code generating section 4.11, in this embodiment of the present invention,
These sinks 5.16 are generated from digital switches 20.21, respectively, and as a result, in this embodiment, these sinks 5.16 have codes that can be arbitrarily set by the parties involved. The point is that there is.

Next, the operation of this embodiment will be explained.

First, the digital switch 20 is operated so that the sync 5 consisting of a code that only the person concerned can understand is outputted from the digital switch 20. Then, in this state, the input data 1 is supplied to the error correction code adding section 2 of the recording system, and using the sink 5 from the digital switch 20, the Wi! , create recording data 8,
This data 8 is recorded on a recording medium 9.

Now, suppose that a person other than the person concerned inputs the data to the reproduction system shown in FIG. 2, for example, in order to reproduce the data recorded on the recording medium 9.

Then, at this time, the sync included in the data 10 read from the recording medium 9 by this reproduction system is a special sync that is arbitrarily set by the party using the digital switch 20 (Fig. 1). On the other hand, the code detection unit 12 has a sink consisting of a combination of codes.
A commonly used standard code type sync is supplied from the code generator 11 and is only tt, so naturally code detection is performed using this standard sync. As a result.

The code detection section 12 does not detect any matching information 14, and the error correction section 13 is made unable to reproduce the data.
Data will be protected.

However, as a matter of course, between the parties.

Since the combination of codes set by the digital switch 2o has been agreed upon in advance, the digital switch 21 in the playback system is set with the same code as the sync code set by the digital switch 2o in the recording system. As a result, the code detection unit 12 of the reproduction system reliably detects the number information 14 at each starting point of each error correction block of the read data 10, and this error is detected. It is possible to reliably extract error-corrected and accurate output data 15 from the correction unit 13.

In such systems, due to their versatility, default values are generally set for the sinks used.

Therefore, in this embodiment, unless special protection is required for private data, this default value is normally set as the sink, and only when necessary, a special All you have to do is set up a suitable sink.

Note that this sink usually uses 2 to 3 bytes of data, so even if you simply calculate it, there are 21'' to 224 possible patterns for this sink, and , Kokura Digital Switch 20.21
As a sync generation unit consisting of a , according to this example.

You can completely protect your data.

Here, the present invention can be expressed as a block diagram as shown in FIG. 4. Here, FIG. 1A corresponds to the embodiment shown in FIG. 1, and the sync generation section here corresponds to the digital switches 20 and 21.

Note that although the sync and generator sections are provided separately for the recording system and the playback system in FIG. If the system and the reproduction system are provided in the same system, they may be combined into a common sync generation section, as shown in FIG. 2(b).

Incidentally, in the embodiments described above, a digital switch is used as the sync generation section, so the block diagram at this time is as shown in FIG. However, the present invention is not limited to this and can be implemented.

This point will be explained below.

First, in FIG. 6(a), a magnetic card reader 26 is used as a sync generating section, and a predetermined magnetic recording card 25 is thereby used.
Read the data recorded in.

This is an embodiment in which a sink 27 (sink 5 or 16) is set, and FIG.
This is an embodiment in which the zinc 30 (sink 5 or 16) is set by reading it with a barcode reader 29.

As mentioned above, in the case of handling multiple sinks with codes different from the default value, in the embodiment using a digital switch, each of these sinks must be memorized, but in the embodiment shown in FIG. According to the report, handling and operation become easier as all that is required is the management of magnetic cards and barcodes.

By the way, in the above embodiment, the sink is directly set, but instead of this.

The sink may be set by executing some calculation.

FIG. 7 shows an embodiment of the present invention having such a configuration.
A sync generator is configured using the arithmetic unit 32, and predetermined data, for example, identification number data 31 of one individual, is inputted into this, and the calculation result is set as sync 33-11=(sink 5 or 16). This is what I did.

FIG. 8 shows an example of the content of calculations performed by the calculation unit 32. Here, as an output, a person who writes/plays at sync-A- other than the default value ■, ■, a person who records @/plays at sync-B- ■, ■, ■, the same, sync-C- Recorded data can be protected by classifying system users into groups such as ■, ■, ■, etc., and assigning identification numbers to each of them. In this embodiment, it goes without saying that the structure of the classification and the number of classifications can be freely determined by changing the calculation contents of the calculation section 32 shown in FIG.

Next, FIG. 9 shows still another embodiment of the present invention, which includes a personal identification number 34 and a recorded data identification number 3.
5 (Type of sink other than the default value to be used - Am~
-a-~ depending on which of -C- is used for the recorded data.
An arithmetic unit 36 is provided which takes as input a number classified into any one of C- to C-, and the arithmetic result of this arithmetic unit 36 is used as a sink 37.

FIG. 10 shows an example of the calculation contents of the calculation section 36, and in this figure, the relationship between the identification number of recorded data and its sync is as follows.

-a-→-A-1-su-→-B-.

-C-→ -C- In addition, in this FIG. 10, the - of the sink indicates that generation is impossible.

As a result, the personal identification number ■ is the data of the identification numbers -a -, -c- of the recorded data.
The recording data identification number -S-1-C- data, and the personal identification number ■ is the recording data identification number -a-.
, -b- can be reproduced.

Therefore, according to this embodiment, data to be protected can be classified into data that can be reproduced by individual users and protected. Even in this case, the configuration of one category and the number thereof can be freely determined by changing the calculation contents of the calculation section 36 shown in FIG.

In the embodiment shown in FIG. 9, the personal identification code may be arbitrarily determined depending on the purpose, such as gender, age, company, etc.

Next, still another embodiment of the present invention will be described with reference to FIG.

This embodiment uses a reproduction timer 38, inputs the time data that will be output from now on as an identification code 39 to a calculation unit 40, and sends the calculation result to a sink 41 (sink 5 or 16).
That is to say.

The contents of the calculation by the calculation unit 40 at this time are as follows.

Playback time ≦ ]゛ →Sync generation playback time〉T →Sync destruction In other words, according to this embodiment, the playback time is equal to the predetermined time T
When within the range, the sync indicating that playback is possible is the calculation unit 40
If the playback time exceeds a predetermined time T, the sink will be destroyed and playback of the data will become impossible. It can be used as a service system that allows data to be used for a predetermined period of time in exchange for payment.

Furthermore, in addition to what has been described above, according to the present invention, data can be easily protected based on various criteria by changing the calculation contents.

Regarding the arithmetic unit in the above embodiments.

It may also be realized by hardware using logic circuits.

It can also be done by software using CPU and memory.1.
It goes without saying that it may also be implemented using a LUT (look-up table) method using ROM, RAM, or the like.

〔Effect of the invention〕

As explained above, according to the present invention, data can be reliably protected simply by using a sink required for error correction without requiring the addition of additional data. This problem can be easily addressed and a digital data protection method can be easily provided.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the digital data protection method according to the present invention, FIG. 2 is a block diagram showing a conventional example of the data processing method, and FIG. 3 is an explanatory diagram of the data structure.
FIG. 4 is an explanatory drawing that clearly shows the present invention, FIG. 5 is an explanatory drawing that shows one embodiment of the present invention, and FIG. 6 shows another embodiment of the present invention. Explanatory diagram, number 7! ! I is an explanatory diagram showing yet another embodiment of the present invention, FIG. 8 is an explanatory diagram of the calculation contents, FIG. 9 is an explanatory diagram showing another embodiment of the invention, and FIG. 10 is an explanatory diagram of the calculation contents. An explanatory diagram, FIG. 11, is an explanatory diagram showing another embodiment of the present invention. 1... Input data, 2... Error correction code addition section, 5... Code signal input, 6... Switch, 7...
...Code addition part, 8...Record data, 9...
- Recording medium, 12...Code detection section, 13...Error correction section, I4...Concordance information, Step 5...Output data, Step 2, 22...Digital switch. 5-11 Court Nobunamijin 6-1-Nuitte 7--Code What JfJ Guo 12--1-To Detection Unit +4--Consistent Information Figure 2 Figure 3 (b) Figure 5 ( a) (b) Calculation contents of calculation section 32, Section 9, Figure 11, Calculation contents

Claims (1)

[Claims] In a digital data processing method that sequentially divides continuous digital data into predetermined lengths and attaches error correction codes to them, and performs error correction on each of these divided pieces of data, there is a A digital data protection method characterized in that the code is configured to have a pin code function.