JP2006065424A - Data storage system, data storage device, similar file recording method to be used for the same and program therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data storage device for reconciling the reduction of a data size and the shortening of a data processing time. <P>SOLUTION: A data storage device 1 calculates the dissimilarity of inputted data and data belonging to a model data group 111 by a similarity deciding part 12, and generates difference data between the input data and model data by a difference generating part 122. When dissimilarity exceeds a dissimilarity threshold, the data storage device 1 transfers the input data name, the model data name, the calculated similarity and the difference data generated during calculation to a data managing part 11. The data managing part 11 compresses the difference data received from the similarity deciding part 12 by a data compressing part 114, and adds the difference data to a compression difference data group 113 for storage. The data managing part 11 associates the compressed difference data name, the input data name received from the similarity deciding part 12 and the model data name and the similarity with each other, and stores the data in a data table. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a data storage system, a data storage device, a similar file recording method used therefor, and a program therefor, and more particularly to a similar file recording method in an information processing system.

  Conventionally, in an information processing system, when an OS (Operating System) is included, a system image is often stored as a backup. However, since the data size of the system image to be stored becomes very large, the capacity of the data recording apparatus is easily pressed.

  In order to solve this, there is a method of compressing and storing the above system image (for example, see Patent Documents 1 and 2), but the system image is independent for each data to be stored. There is a problem that compression using a similar part cannot be performed, and it takes time to compress and decompress the data size.

JP 2003-67232 A JP 2003-99308 A

  In the conventional information processing system described above, there is a method of compressing input data to reduce the size of data to be recorded when recording arbitrary data on a data recording apparatus, but depending on the data, the size is reduced after compression. There are cases where data with a low rate exists and the time for the compression process and the decompression process is not suitable.

  Accordingly, an object of the present invention is to provide a data storage system, a data storage device, a similar file recording method used therefor, and a program thereof that can solve the above-described problems and achieve both reduction in data size and reduction in data processing time. It is to provide.

  A data storage system according to the present invention is a data storage system including a computer including a data recording device capable of reading and writing data, and when a plurality of data is recorded on the data recording device, a similar part between the data is recorded. The data recording apparatus is provided with means for performing compression using the compression, and the total size of the plurality of data is reduced by the compression.

Another data storage system according to the present invention is a data storage system comprising a computer including a data recording device capable of reading and writing data,
Similarity determination means for calculating dissimilarity between input data and data belonging to a previously accumulated model data group, difference generation means for generating difference data between the input data and the model data, and the difference Data compression means for compressing the difference data received from the generation means, and a data table for storing the compressed difference data name in association with the input data name and model data name and similarity received from the similarity determination means The data recording device includes data management means including

  A data storage device according to the present invention is a data recording device capable of reading and writing data, and includes a means for performing compression using a similar portion between the data when recording a plurality of data, and the plurality of the data by the compression. The total size of the data is reduced.

Another data storage device according to the present invention is a data recording device capable of reading and writing data,
Similarity determination means for calculating dissimilarity between input data and data belonging to a previously accumulated model data group, difference generation means for generating difference data between the input data and the model data, and the difference Data compression means for compressing the difference data received from the generation means, and a data table for storing the compressed difference data name in association with the input data name and model data name and similarity received from the similarity determination means Including data management means.

  A similar file recording method according to the present invention is a similar file recording method used in a data recording device capable of reading and writing data, and when recording a plurality of data on the data recording device side, similar portions between the data are recorded. And a step of performing compression using the data, and the total size of the plurality of data is reduced by the compression.

Another similar file recording method according to the present invention is a similar file recording method used in a data recording device capable of reading and writing data,
On the data recording device side, calculating the dissimilarity between the input data and data belonging to the model data group accumulated in advance, generating difference data between the input data and the model data, Compressing the difference data, and storing the compressed difference data name, the input data name, the model data name, and the similarity in a data table in association with each other.

  A program of a similar file recording method according to the present invention is a program of a similar file recording method used in a data recording device capable of reading and writing data, and when recording a plurality of data on a computer on the data recording device side, A process of performing compression using similar parts between data is executed, and the total size of the plurality of data is reduced by the compression.

  Another similar file recording method program according to the present invention is a similar file recording method program used in a data recording device capable of reading and writing data, and the input data is stored in advance in the computer on the data recording device side. Processing for calculating dissimilarity with respect to data belonging to the model data group, processing for generating difference data between the input data and the model data, processing for compressing the difference data, and compressed difference data name And a process of storing the data in the data table in association with the input data name, the model data name, and the similarity.

  That is, the data storage device of the present invention is a system composed of a computer equipped with a data recording device capable of reading and writing data. When recording a plurality of data in the data recording device, the total data of similar data groups It is characterized by reducing the size.

  In the data storage device of the present invention, the total size of a plurality of data is reduced by compression using a similar portion between the data, and at the same time, the degree of time required for compression and decompression is determined by determining the similarity between the data. When there is no compression / decompression effect, the compression / decompression time is omitted.

  More specifically, in the data storage device of the present invention, the similarity determination unit calculates the dissimilarity between the data input to the data storage device and the data belonging to the model data group of the data storage device, and at the same time generates a difference. The unit generates difference data between the input data and the model data.

  In the data storage device of the present invention, when the dissimilarity exceeds the dissimilarity threshold as a result of the above calculation, the input data name, the model data name, the calculated similarity, and the difference data generated during the calculation are Pass to the data management department.

  The data management unit compresses the difference data received from the similarity determination unit by the data compression unit, and stores it in addition to the compressed difference data group. Further, the data management unit stores the compressed difference data name, the input data name received from the similarity determination unit, the model data name and the similarity in association with each other in the data table. As a result, the information processing apparatus of the present invention can store data with a reduced size.

  Further, in the data storage device of the present invention, two or more similar data are subjected to exclusive OR operation in the difference generation unit to obtain a difference, improve the logical continuity of the data, and compress and record only the difference. By reducing the size.

  Furthermore, in the data storage device of the present invention, when the dissimilarity between files in the similarity determination unit is less than the dissimilarity threshold set by the threshold setting means, the effect of the difference generation process and the compression process is low. It is possible to record data without making a decision and consuming processing time without performing processing.

  Thereby, in the data storage device of the present invention, it is possible to achieve both reduction in data size and reduction in data processing time by adding a compression condition for recording data.

  According to the present invention, it is possible to achieve both the reduction in data size and the reduction in data processing time by adopting the configuration and operation described below.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a data storage device according to an embodiment of the present invention. In FIG. 1, the data storage device 1 includes a data management unit 11, a similarity determination unit 12, a data input unit 13, a data restoration unit 14, a data output unit 15, and a recording medium 16. Yes.

  The data management unit 11 includes a model data group 111, a data table 112, a compression difference data group 113, a data compression unit 114, and a data decompression unit 115.

  The similarity determination unit 12 includes a difference generation unit 122 that generates difference data and a dissimilarity 121, and a threshold setting unit 124 that sets a dissimilarity threshold 123. The dissimilarity 121 sets the dissimilarity threshold 123. Determine if it exceeds.

  The model data group 111 is data serving as a model for determining the similarity. When it is determined that there is no similar data in the apparatus, the input data is recorded as uncompressed data as model data. The compressed difference data group 113 is data obtained by compressing the difference between the model data and the input data when it is determined that there is similar model data in the apparatus. The data table 112 manages the model data name, the compressed difference data name, and the similarity between these two data as elements of the input data name.

  The data compression unit 114 compresses the difference data passed from the difference generation unit 122 and records it in addition to the compressed difference data group 113. The data decompression unit 115 decompresses the data included in the compressed differential data group 113 and passes it to the data decompression unit 14.

  The difference generation unit 122 calculates the dissimilarity 121 from the cumulative sum of the differences while generating an exclusive OR of the input data and the data included in the model data group 111 as a difference.

  The data restoration unit 14 outputs an exclusive OR of the difference data decompressed by the data decompression unit 115 and the data included in the model data group 111 corresponding to the difference as restoration data.

  The recording medium 16 stores programs executed by the data management unit 11, the similarity determination unit 12, the data input unit 13, the data restoration unit 14, and the data output unit 15 of the data storage device 1. The program is for realizing processing of each unit of the data storage device 1 described later.

  The data storage device 1 calculates the dissimilarity 121 for the input data and the data belonging to the model data group 111 possessed by the similarity determination unit 12. At the same time, the difference generation unit 122 generates difference data between the input data and the model data. When the dissimilarity exceeds the dissimilarity threshold 123 as a result of the calculation, the similarity determination unit 12 uses the input data name, the model data name, the calculated similarity, and the difference data generated during the calculation as a data management unit. 11

  In the data management unit 11, the data compression unit 114 compresses the difference data received from the similarity determination unit 12 and stores it in addition to the compressed difference data group 113. In addition, the data management unit 11 stores the compressed difference data name, the input data name received from the similarity determination unit 12, the model data name, and the similarity in association with each other in the data table 112. Thereby, in this embodiment, the data can be stored with a reduced size.

  In FIG. 1, in the present embodiment, two or more similar data are subjected to exclusive OR in the difference generation unit 121 to obtain a difference, to increase the logical continuity of the data, and only the difference is compressed and recorded. By doing so, the data size is reduced. Further, in this embodiment, when the dissimilarity 121 between files is less than the dissimilarity threshold 123 set by the threshold setting unit 124 in the similarity determination unit 12, the effect of the difference generation process and the compression process is low. It is possible to record data without determining and performing processing and without consuming processing time.

  FIG. 2 is a block diagram showing the configuration of the data table 112 of FIG. In FIG. 2, the data table 112 includes an input data name group 1121, a compressed difference data name group 1122, a model data name group 1123, and a dissimilarity group 1124.

  The input data name group 1121 includes all input data names recorded in the apparatus. In particular, the input data name of the input data recorded in the apparatus as compressed differential data is obtained by converting the compressed differential data name into the compressed differential data name group 1122. In addition, the model data name used when generating the difference data is included in the model data name group 1123, and the dissimilarity is included in the dissimilarity group 1124 as an element.

  3 to 7 are flowcharts showing the operation of the data storage device 1 according to one embodiment of the present invention. The operation of the data storage device 1 according to one embodiment of the present invention will be described with reference to FIGS. The processing shown in FIGS. 3 to 7 is realized by each part of the data storage device 1 executing the program of the recording medium 16.

  The data recording apparatus 1 needs to set a dissimilarity threshold before data recording, and as shown in FIG. 3, the dissimilarity threshold 123 is set by the threshold setting means 124 (step S1 in FIG. 3).

  The operation of the data recording apparatus 1 when recording input data is shown in FIG. In the data recording apparatus 1, data is input from the outside by the data input means 13, and the input data is passed to the similarity determination unit 12 (step S11 in FIG. 4).

  The data management unit 11 checks whether there is one or more model data in the model data group 111, and further checks whether there is model data whose dissimilarity is not checked (step S12 in FIG. 4). If there is no model data, or if there is no model data whose dissimilarity is not checked, the input data is transferred from the similarity determination unit 12 to the data management unit 11 and model data group as model data 111 (step S13 in FIG. 4).

  On the other hand, if there is one or more model data whose dissimilarity can be checked, the data management unit 11 reads one model data in the recording order from the model data group 111 and passes it to the similarity determination unit 12 (step in FIG. 4). S14). The similarity determination unit 12 calculates an exclusive OR between the top 1 bit of the input data and the top 1 bit of the model data passed from the data management unit 11 by the difference generation unit 122 to obtain difference data.

  Further, every time the difference generation unit 122 calculates the difference of data, the difference generation unit 122 calculates the cumulative sum of the exclusive OR, and the value obtained by dividing the cumulative sum by the larger bit size of the input data size or the model data size is obtained. The dissimilarity is calculated as 121 (step S15 in FIG. 4).

  The similarity determination unit 12 checks whether or not the dissimilarity 121 does not exceed the dissimilarity threshold 123 (step S16 in FIG. 4). It is checked whether there is data that can be checked in the model data (step S12 in FIG. 4).

  If the dissimilarity 121 does not exceed the dissimilarity threshold 123, the similarity determination unit 12 checks whether there is a next bit necessary for generating the next difference between the model data and the input data (see FIG. 4 step S17). If there is the next bit, the similarity determination unit 12 generates a difference based on the next bit and calculates the dissimilarity 121 (step S15 in FIG. 4).

  When there is no next bit, the similarity determination unit 12 checks whether there is a next bit in either the model data or the input data (steps S17 and S18 in FIG. 4). When there is a bit in either one, the similarity determination unit 12 sets the next bit of the missing data to 0 (step S19 in FIG. 4). And the similarity determination part 12 produces | generates the difference with the next bit of the data which is not insufficient, and calculates the dissimilarity 121 (FIG. 4, step S15).

  When there is no next bit in both the model data and the input data, the similarity determination unit 12 passes the generated difference bit string to the data management unit 11 and is compressed by the data compression unit 114 (step S20 in FIG. 4). .

  Thereafter, the data management unit 11 uses the input data name as a reference tag, the data name of the difference data compressed by the data compression unit 114, the data name of the model data obtained by taking the difference from the input data, and the calculated dissimilarity Is recorded in the data table 112 as an element thereof (step S21 in FIG. 4). The differential data compressed by the data compression unit 114 is included in the compressed differential data group 113 as compressed differential data (step S22 in FIG. 4).

  The operation at the time of reading the recording data of the data recording apparatus 1 is shown in FIG. The data management unit 11 of the data recording apparatus 1 checks whether there is data having the data name for which the read request has been received in the model data group 111 (step S31 in FIG. 5). If there is data, the data management unit 11 passes the corresponding model data to the data output means 15 and outputs it to the outside (step S37 in FIG. 5).

  If the data that received the read request is not model data, the data management unit 11 checks whether the data name that received the read request is in the input data name group 1121 of the data table 112 (step S32 in FIG. 5). If there is not, the process is terminated.

  If the data name that has received the read request is in the input data name group 1121, the data management unit 11 refers to the element of the input data from the compressed difference data name group 1122 and the model data name group 1123 (step S33 in FIG. 5). . The data management unit 11 reads the data having the referenced compressed differential data name from the compressed differential data group 113, decompresses it with the data decompression unit 115, and passes it to the data restoration unit 14 as differential data (step S34 in FIG. 5).

  The data management unit 11 reads the data having the referenced model data name from the model data group 111 and passes it to the data restoration unit 14 (step S35 in FIG. 5). In the data restoration unit 14, the exclusive OR of the difference data and the model data delivered from the data management unit 11 is delivered to the data output unit 15 as restoration data, and is output to the outside (step S36 in FIG. 5).

  The operation of the data recording apparatus 1 when deleting the recording data is shown in FIGS. The data management unit 11 of the data recording apparatus 1 checks whether or not the data name that has received the deletion request is in the input data name group 1121 of the data table 112 (step S41 in FIG. 6). If there is an input data name having the data name for which the deletion request has been received, the data management unit 11 refers to the compressed differential data name as the element, and deletes the compressed differential data having the referenced data name (step S42 in FIG. 6). ), The input data name having the data name for which the deletion request has been received and its elements are deleted from the data table 112 (step S43 in FIG. 6), and the process ends.

  If the data having the data name for which the deletion request has been received is not in the input data name group 1121, the data management unit 11 checks whether the model data having the data name for which the deletion request has been received is in the model data group 111 (FIG. 6). In step S44), if there is no model data having the data name for which the deletion request has been received, the process is terminated.

  If there is model data having the data name that has received the deletion request, the data management unit 11 does not have the data name that has received the deletion request in the model data name group 1123 that is an element in the input data name group 1121 of the data table 112. If there is no data name for which the deletion request has been received, the model data having the data name for which the deletion request has been received is deleted from the model data group 111 (step S53 in FIG. 7). finish.

  When there is a data name for which a deletion request is received in the model data name group 1123, the data management unit 11 refers to the dissimilarity group 1124 for input data having the model data name to be deleted as an element, and has the minimum dissimilarity. Reference is made to the compression difference data name and model data name of the input data (step S46 in FIG. 6).

  Further, the data management unit 11 reads data having the referenced model data name from the model data group 111 and passes it to the data restoring unit 14, and reads data having the referenced compressed difference data name from the compressed difference data group 113 to decompress the data. The difference data is converted into differential data by the unit 115 and then transferred to the data restoration unit 14 (step S47 in FIG. 6).

  The data restoration unit 14 uses the exclusive OR of the difference data and model data delivered from the data management unit 11 as restoration data, and passes the data to the data management unit 11. The data management unit 11 adds the data passed from the data restoration unit 14 as new model data to the model data group 111 (step S48 in FIG. 6).

  The data management unit 11 deletes the data name of the restored input data and its elements from the data table 112, and deletes the compressed differential data used for the restoration from the compressed differential data group 113 (step S49 in FIG. 6).

  Next, the data management unit 11 checks whether there is any other input data having the model name to be deleted in the data table 112 (step S50 in FIG. 7). If there is no other input data, the data management unit 11 receives a deletion request. The model data having the data name is deleted from the model data group 111 (step S53 in FIG. 7), and the process ends.

  If there is other input data, the data management unit 11 restores the input data by the data restoration unit 14 in the same manner as the processing described above, deletes the input data name and its elements from the data table 112, and restores them. The used compression difference data is deleted from the compression difference data group 113. The data restoration unit 14 passes the restored data to the similarity determination unit 12 (step S51 in FIG. 6).

  The similarity determination unit 12 determines the similarity between the data passed from the data restoration unit 14 and the new model data restored with the minimum dissimilarity, in the same manner as the data input from the outside. Recording is performed (step S52 in FIG. 6). The data management unit 11 checks again whether there is any other input data having the model name to be deleted in the data table 112 (step S50 in FIG. 6).

  As described above, in this embodiment, it is possible to achieve both reduction in data size and reduction in data processing time by adding recording data compression conditions.

  FIG. 8 is a block diagram showing the configuration of a data storage system according to another embodiment of the present invention. In FIG. 8, a data storage system according to another embodiment of the present invention comprises a computer 2, a data recording medium 3, a recording medium 4, and a medium transport path 100 connecting the computer 2 and the data recording medium 3. ing. The transport medium transport path 100 is a network particularly when the data recording medium 3 is a recording device on the network.

  The computer 2 includes a data recording medium reading unit 22 for reading data on the data recording medium 3 and a virtual data output unit executing unit 21 for executing the virtual data output unit 31 of the data recording medium 3. The recording medium 4 stores a program executed by the computer 2, and the processing operation of each unit is realized by the computer 2 executing the program.

  The data recording medium 3 includes a recording medium such as a CD-ROM (Compact Disc-Read Only Memory) and a DVD-ROM (Digital Versatile Disc-Read Only Memory) having a virtual data output unit 31. Including.

  The virtual data output unit 31 includes a configuration in which only a portion necessary for outputting data is extracted from the configuration illustrated in FIG. That is, the virtual data output unit 31 includes a data management unit 311, a data restoration unit 312, and a data output unit 313, and the data management unit 311 includes a model data group 3111, a data table 3112, and a compressed difference data group. 3113 and data decompression means 3114.

  When the data recording medium 3 is generated, the model data group 3111, the data table 3112, and the compression difference data group 3113 of the virtual data output unit 31 replicate the state in which data is recorded with the configuration shown in FIG.

  FIG. 9 is a flowchart showing an operation when the computer 2 of FIG. 8 reads data from the data recording medium 3. The operation when the computer 2 according to another embodiment of the present invention reads data from the data recording medium 3 will be described with reference to FIGS. Note that the processing shown in FIG. 9 is realized by the computer 2 executing the program of the recording medium 4.

  The computer 2 reads the virtual data output unit 31 of the data recording medium 3 by the data recording medium reading unit 22 and passes it to the virtual data output unit executing unit 21 (step S61 in FIG. 9).

  The virtual data output unit executing means 21 executes the same operation (the operation shown in steps S31 to S37 in FIG. 5) as the virtual data output unit 31 delivered from the data recording medium reading means 22 when reading the configuration shown in FIG. The target data (request data) is taken out (step S62 in FIG. 9).

  In the present embodiment, when data included in the model data group 3111 is read while reducing the data size to be recorded on the data recording medium 3, all the data is read at a higher speed than the compressed medium. Can do.

  In the information recording field of the information processing industry, the present invention can be used for backup of information systems, distribution of information systems using information recording media to different platforms, and the like.

It is a block diagram which shows the structure of the data storage device by one Example of this invention. It is a block diagram which shows the structure of the data table of FIG. 4 is a flowchart illustrating an operation of the data storage device according to the embodiment of the present invention. 4 is a flowchart illustrating an operation of the data storage device according to the embodiment of the present invention. 4 is a flowchart illustrating an operation of the data storage device according to the embodiment of the present invention. 4 is a flowchart illustrating an operation of the data storage device according to the embodiment of the present invention. 4 is a flowchart illustrating an operation of the data storage device according to the embodiment of the present invention. It is a block diagram which shows the structure of the data storage system by the other Example of this invention. It is a flowchart which shows operation | movement when the computer of FIG. 8 reads data from a data recording medium.

Explanation of symbols

1 Data storage device
2 computers
3 Data recording media
4,16 Recording medium
11 Data management department
12 Similarity determination unit
13 Data input means 14, 312 Data restoration section 15,313 Data output means
21 Virtual data output unit execution means
22 Data recording medium reading means
31 Virtual data output unit 111, 3111 Model data group 112, 3112 Data table 113, 3113 Compression difference data group
114 Data compression unit
115 Data decompression unit
121 Dissimilarity
122 Difference generator
123 Dissimilarity threshold
124 threshold setting means
1121 Input data name group
1122 Compression difference data name group
1123 Model data name group
1124 Dissimilarity group
3114 Data decompression means

Claims (20)

  A data storage system comprising a computer including a data recording device capable of reading and writing data, wherein the means for performing compression using a similar portion between the data when recording a plurality of data in the data recording device A data storage system comprising a data recording device, wherein the total size of the plurality of data is reduced by the compression. Means for determining the similarity between the data in the data recording device;
2. The data storage according to claim 1, wherein the compression and the decompression are omitted when any of the compression effect and the decompression effect with respect to a time required for at least one of the compression and decompression of the data is not accompanied. system. A data storage system comprising a computer including a data recording device capable of reading and writing data,
Similarity determination means for calculating dissimilarity between input data and data belonging to a previously accumulated model data group, difference generation means for generating difference data between the input data and the model data, and the difference Data compression means for compressing the difference data received from the generation means, and a data table for storing the compressed difference data name in association with the input data name and model data name and similarity received from the similarity determination means A data storage system comprising: a data management means including: the data recording device.   When the dissimilarity exceeds the dissimilarity threshold in the calculation result of the similarity determination means, the input data name, the model data name, the calculated similarity, and the difference data generated during the calculation 4. The data storage system according to claim 3, wherein the data storage system is passed to the data management means.   5. The data storage system according to claim 4, wherein when the dissimilarity is less than the dissimilarity threshold, the difference generation process and the compression process of the data are suppressed. The difference generation means generates the difference data by taking an exclusive OR of two or more similar data,
The data storage system according to any one of claims 3 to 5, wherein the total size of the plurality of data is reduced by compressing and recording only the difference data.   A data recording apparatus capable of reading and writing data, and having means for performing compression using a similar portion between the data when recording a plurality of data, and reducing the total size of the plurality of data by the compression A data recording apparatus. Means for determining the degree of similarity between the data;
8. The data storage according to claim 7, wherein the compression and the decompression are omitted when either the compression effect or the decompression effect with respect to the time required for at least one of the compression and decompression of the data is not accompanied. apparatus. A data recording device capable of reading and writing data,
Similarity determination means for calculating dissimilarity between input data and data belonging to a previously accumulated model data group, difference generation means for generating difference data between the input data and the model data, and the difference Data compression means for compressing the difference data received from the generation means, and a data table for storing the compressed difference data name in association with the input data name and model data name and similarity received from the similarity determination means And a data management unit including the data management means.   When the dissimilarity exceeds the dissimilarity threshold in the calculation result of the similarity determination means, the input data name, the model data name, the calculated similarity, and the difference data generated during the calculation The data storage device according to claim 9, wherein the data storage device passes the data management means.   11. The data storage device according to claim 10, wherein when the dissimilarity is less than the dissimilarity threshold, the data difference generation processing and compression processing are suppressed. The difference generation means generates the difference data by taking an exclusive OR of two or more similar data,
The data storage device according to any one of claims 9 to 11, wherein the total size of the plurality of data is reduced by compressing and recording only the difference data.   A similar file recording method used in a data recording device capable of reading and writing data, comprising: a step of performing compression using a similar portion between the data when recording a plurality of data on the data recording device side A similar file recording method, wherein the compression reduces the total size of the plurality of data. The data recording device side includes a step of determining the degree of similarity between the data,
14. The similar file according to claim 13, wherein the compression and the decompression are omitted when either the compression effect or the decompression effect on the time required for at least one of the data compression and decompression is not accompanied. Recording method. A similar file recording method used in a data recording device capable of reading and writing data,
On the data recording device side, calculating the dissimilarity between the input data and data belonging to the model data group accumulated in advance, generating difference data between the input data and the model data, A method of recording a similar file, comprising: compressing the difference data; and storing the compressed difference data name, the input data name, the model data name, and the similarity in a data table. .   In the calculation result of the step of calculating the dissimilarity, when the dissimilarity exceeds a dissimilarity threshold, the input data name, the model data name, the calculated similarity, and the difference generated during the calculation 16. The similar file recording method according to claim 15, wherein the data is transferred to the step of storing the data in the data table.   17. The similar file recording method according to claim 16, wherein when the dissimilarity is less than the dissimilarity threshold, the difference generation process and the compression process of the data are suppressed. The step of generating the difference data generates the difference data by taking an exclusive OR of two or more similar data,
17. The similar file recording method according to claim 15, wherein the total size of the plurality of data is reduced by compressing and recording only the difference data.   A program of a similar file recording method used in a data recording device capable of reading and writing data, and compressing using a similar portion between the data when recording a plurality of data in a computer on the data recording device side A program for executing processing and reducing the total size of the plurality of data by the compression. A program of a similar file recording method used in a data recording device capable of reading and writing data, wherein the degree of dissimilarity between data input to a computer on the data recording device side and data belonging to a model data group stored in advance A process for calculating the difference data between the input data and the model data, a process for compressing the difference data, and the compressed difference data name, the input data name, the model data name, and the similarity A program for executing a process of storing data in a data table with association.

Images