JP2012235289A - Compression apparatus, compression method, compression program and decompression apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently compress data.SOLUTION: A compression apparatus 100 acquires log data and extracts time information. The compression apparatus 100 divides the time information into a predetermined data width to generate a plurality of byte groups. The compression apparatus 100 compares adjacent values and calculates differential values in each byte group to generate differential value information 140a. The compression apparatus 100 compresses the differential value information 140a by, for example, an LZ77 algorithm, to generate compressed data.

Description

  The present invention relates to a compression device and the like.

  Corresponding to the time information, the engine speed of the car, the speed of the car, etc. may be stored in the storage device as log data, and the performance of the car may be inspected by analyzing the log data. In the future, in addition to the engine speed and speed, the number of items to be collected tends to increase, so it is required to reduce the amount of log data.

  In the prior art, the amount of data is reduced without losing data by encoding log data using a data compression technique. As a specific data compression technique, for example, there is a so-called LZ77 system.

  FIG. 15 is a diagram for explaining an LZ77 data compression technique. In the LZ77 system, the same character repetition is found from the data buffer, and the repetition is encoded with the position and the matching length. For example, “compress decompression” is stored in the data buffer 10 of FIG. In the data buffer 10, the 0th to 7th characters and the 11th to 18th characters are "compress", and 8 characters match. For this reason, in the LZ77 system, the 11th to 18th characters are encoded to (0, 8), and the remaining characters are left as they are. For example, the encoded data is “compress de (0,8) ion”.

  Note that some conventional techniques perform data compression after performing preprocessing for extracting log data separately for each item. FIG. 16 is a diagram for explaining the related art. As shown in FIG. 16, the data buffer 15 has a region 15a for storing time information, a region 15b for storing engine speed, and a region 15c for storing speed. In the prior art, data is extracted from each of the areas 15a, 15b, and 15c, and data compression is performed for each extracted data.

JP-A-11-355280 JP 2006-302161 A

  However, the above-described prior art has a problem that data cannot be efficiently compressed.

  Time information is often stored in a storage device as a set with other items. Here, the information of each item such as the engine speed and the speed is often related to each other, but the time information increases by a fixed amount regardless of other items. For this reason, when the time information and other items are set and encoded at once, the time information becomes an obstacle and the data cannot be efficiently compressed. In addition, even if data is compressed separately for each item as in the above-described prior art, time information cannot be compressed efficiently.

  The disclosed technology has been made in view of the above, and an object thereof is to provide a compression device or the like that can efficiently compress data.

  The disclosed compression apparatus includes a dividing unit, a difference unit, and a compression unit. The dividing unit divides a plurality of continuous measurement data for each predetermined data width. The difference unit acquires each measurement data divided for each predetermined data width by the division unit, and includes a difference value for each predetermined data width by taking a difference for each divided data width of each measurement data. Generate difference data. The compression unit compresses a difference value for each predetermined data width included in the difference data.

  According to the disclosed compression device, there is an effect that data can be efficiently compressed.

FIG. 1 is a diagram illustrating a configuration of a compression device according to the present embodiment. FIG. 2 is a diagram illustrating an example of a data structure of log data. FIG. 3 is a diagram illustrating an example of a data structure of time information. FIG. 4 is a diagram illustrating an example of time information divided every 8 bits. FIG. 5 is a diagram for explaining the processing of the difference value calculation unit. FIG. 6 is a diagram (1) illustrating an example of the difference byte group. FIG. 7 is a diagram illustrating the configuration of the restoration apparatus according to the present embodiment. FIG. 8 is a diagram for explaining the processing of the adding unit. FIG. 9 is a flowchart showing the processing procedure of the compression apparatus. FIG. 10 is a flowchart illustrating the processing procedure of the restoration apparatus. FIG. 11 is a diagram for explaining other processing of the difference value calculation unit. FIG. 12 is a diagram (2) illustrating an example of the difference byte group. FIG. 13 is a diagram illustrating an example of a computer that executes a compression program. FIG. 14 is a diagram illustrating an example of a computer that executes a restoration program. FIG. 15 is a diagram for explaining an LZ77 data compression technique. FIG. 16 is a diagram for explaining the related art.

  Hereinafter, embodiments of a compression device, a compression method, a compression program, and a decompression device disclosed in the present application will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  First, the structure of the compression apparatus concerning a present Example is demonstrated. FIG. 1 is a diagram illustrating a configuration of a compression device according to the present embodiment. As illustrated in FIG. 1, the compression device 100 includes an item division unit 110, a byte division unit 120, a difference value calculation unit 130, a storage unit 140, and a data compression unit 150.

  The item dividing unit 110 is a processing unit that acquires log data in which time information, engine speed, and speed are associated, and divides the time information included in the log data and other items. The item dividing unit 110 outputs the time information to the byte dividing unit 120 and causes the storage unit 140 to store information on other items. The log data may be stored in a storage device, and the item dividing unit 110 may acquire the log data from the storage device.

  Here, an example of the data structure of log data will be described. FIG. 2 is a diagram illustrating an example of a data structure of log data. As shown in FIG. 2, the log data 20 has an area 20a for storing time information, an area 20b for storing engine speed information, and an area 20c for storing speed information. For example, the data width of the entire area 20a is 32 bits, and a numerical value is stored every 8 bits. The entire data width of the area 20b is 64 bits, and a numerical value is stored every 8 bits. The entire data width of the area 20c is 64 bits, and a numerical value is stored every 8 bits.

  The item dividing unit 110 outputs the time information stored in the area 20a to the byte dividing unit 120. In addition, the item dividing unit 110 stores the information stored in the area 20b and the area 20c in the storage unit 140. In the following description, the engine speed information and the speed information stored in the areas 20b and 20c are referred to as other item information.

  The byte dividing unit 120 is a processing unit that divides time information into predetermined data widths. For example, the byte dividing unit 120 divides time information every 8 bits (1 byte). The byte dividing unit 120 outputs the time information divided for each predetermined data width to the difference value calculating unit 130.

  Here, the processing of the byte dividing unit 120 will be specifically described. FIG. 3 is a diagram illustrating an example of a data structure of time information. The time information 30 shown in FIG. 3 has a data width of 32 bits and stores a numerical value every 8 bits. The time information 30 indicates a certain time in units of one line, and each time is arranged in ascending order. Note that the same time may be continuously arranged.

  When the byte division unit 120 divides the time information shown in FIG. 3 into 8-bit time information, the result is shown in FIG. FIG. 4 is a diagram illustrating an example of time information divided every 8 bits. As shown in FIG. 4, the byte dividing unit 120 divides the time information 30 into byte groups 31 to 34.

  The difference value calculation unit 130 is a processing unit that acquires a byte group and generates difference value information by taking a difference between values before and after being included in the byte group. The difference value calculation unit 130 stores the difference value information in the storage unit 140.

  Here, the processing of the difference value calculation unit 130 will be specifically described. FIG. 5 is a diagram for explaining the processing of the difference value calculation unit. The byte groups 35 a to 38 a in FIG. 5 are byte groups acquired from the byte dividing unit 120.

  The difference value calculation unit 130 compares the previous and next values for each byte group, calculates a difference value, and generates difference byte groups 35b to 38b. Here, as an example, a case where the difference value calculation unit 130 generates the difference byte group 35b from the byte group 35a will be described.

  The difference value calculation unit 130 stores the value of the head t11 of the byte group 35a as it is at the head of the difference byte group 35b. Subsequently, the difference value calculation unit 130 stores a value obtained by subtracting t11 from t21 in the second of the difference byte group 35b. Subsequently, the difference value calculation unit 130 stores a value obtained by subtracting t21 from t31 in the third of the difference byte group 35b. By sequentially executing such processing, the difference value calculation unit 130 generates a difference byte group 35b from the byte group 35a. Similarly, the difference value calculation unit 130 generates difference byte groups 36b to 38b from the byte groups 36a to 38a. The difference information includes difference byte groups 35b to 38b.

  Here, an example of the difference byte group obtained from the byte groups 31 to 34 shown in FIG. 4 will be described. FIG. 6 is a diagram (1) illustrating an example of the difference byte group. As illustrated in FIG. 6, the difference value calculation unit 130 generates difference byte groups 41 to 44 by comparing previous and next values for each byte group and taking a difference.

  The storage unit 140 is a storage device that stores difference value information 140a and other item information 140b. The storage unit 140 corresponds to, for example, a semiconductor memory device such as a random access memory (RAM), a read only memory (ROM), and a flash memory, or a storage device such as a hard disk or an optical disk.

  The difference value information 140a includes, for example, each of the difference byte groups 41 to 44 described above. The other item information 140b includes engine speed information and speed information. The information on the engine speed and the information on the speed correspond to the information stored in the log data areas 20b and 20c.

  The data compression unit 150 is a processing unit that generates compressed data by compressing the difference value information 140 a and the other item information 140 b stored in the storage unit 140. For example, the data compression unit 150 outputs the generated compressed data to an external device.

  The data compression unit 150 compresses the difference value information 140a for each difference byte group. As shown in FIG. 6, the difference byte groups 41 to 44 can increase the compression efficiency because the same numerical values are continuous. For example, the data compression unit 150 compresses the difference byte groups 41 to 44 by the LZ77 method. Further, the data compression unit 150 compresses the other item information 140b by the LZ77 method.

  Incidentally, the item division unit 110, the byte division unit 120, the difference value calculation unit 130, and the data compression unit 150 illustrated in FIG. 1 are integrated with, for example, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). Corresponds to the device. The processing units 110, 120, 130, and 150 correspond to electronic circuits such as a CPU and an MPU (Micro Processing Unit), for example.

  Next, the configuration of the decompression device that decompresses the compressed data generated by the compression device 100 illustrated in FIG. 1 will be described. FIG. 7 is a diagram illustrating the configuration of the restoration apparatus according to the present embodiment. As illustrated in FIG. 7, the restoration device 200 includes a data restoration unit 210, a storage unit 220, an addition unit 230, a byte integration unit 240, and an item integration unit 250.

  The data restoration unit 210 restores the compressed difference value information and the compressed other item information included in the compressed data, and stores the restored difference value information and the restored other item information in the storage unit 220. For example, when the compressed data is compressed by the LZ77 method, the data restoration unit 210 restores the compressed data based on the repetition position and the matching length in the same manner as in the conventional technique.

  The storage unit 220 is a storage unit that stores difference value information 220a and other item information 220b. The storage unit 220 corresponds to, for example, a semiconductor memory device such as a RAM, a ROM, or a flash memory, or a storage device such as a hard disk or an optical disk.

  The difference value information 220a includes a plurality of difference byte groups decoded from the compressed data. For example, each difference byte group becomes the difference byte group 41 to 44 shown in FIG. The other item information 220b includes engine speed information and speed information.

  The adding unit 230 is a processing unit that acquires a difference byte group and generates a plurality of byte groups before taking a difference by adding values before and after the difference byte group. The adding unit 230 outputs a plurality of byte groups to the byte integrating unit 240.

  Here, the processing of the adding unit 230 will be specifically described. FIG. 8 is a diagram for explaining the processing of the adding unit. The difference byte groups 51a to 54a in FIG. 8 are included in the difference value information 220a.

  The adding unit 230 generates byte groups 51b to 54b by adding the previous and subsequent values for each difference byte group. Here, as an example, a case where the adding unit 230 generates the byte group 51b from the difference byte group 51a will be described.

  The adding unit 230 stores the value of the top t11 of the difference byte group 51a as it is at the top of the byte group 51b. Subsequently, the adding unit 230 stores a value obtained by adding t11 to t21 in the second byte group 51b. Subsequently, the adding unit 230 stores a value obtained by adding t21 to t31 in the third byte group 51b. By sequentially executing such processing, the adding unit 230 generates a byte group 51b from the difference byte group 51a. Similarly, the adding unit 230 generates byte groups 52b to 54b from the difference byte groups 52a to 54a.

  For example, the adding unit 230 generates the byte groups 31 to 34 shown in FIG. 4 from the difference byte groups 41 to 44 shown in FIG.

  The byte integration unit 240 is a processing unit that generates time information by integrating each byte group. The byte integration unit 240 outputs the time information 30 to the item integration unit 250. For example, the byte integration unit 240 generates the time information 30 of FIG. 3 by integrating the byte groups 31 to 34 shown in FIG.

  The item integration unit 250 is a processing unit that generates log data in which the time information, the engine speed, and the speed are associated with each other by integrating the time information 30 and the other item information 220b. For example, the item integration unit 250 outputs the generated log data to an external device.

  Next, the processing procedure of the compression apparatus 100 shown in FIG. 1 will be described. FIG. 9 is a flowchart showing the processing procedure of the compression apparatus. For example, the process illustrated in FIG. 9 is executed when log data is acquired.

  As shown in FIG. 9, the compression apparatus 100 acquires log data, divides time information and other item information (step S101), and divides the time information into bytes (step S102). The compression apparatus 100 compares the previous and next values for each byte group, and generates difference value information (step S103).

  The compression device 100 compresses the difference value information 140a and the other item information 140b in the storage unit 140 (step S104), and outputs compressed data (step S105).

  Next, a processing procedure of the restoration device 200 illustrated in FIG. 7 will be described. FIG. 10 is a flowchart illustrating the processing procedure of the restoration apparatus. For example, the process shown in FIG. 10 is executed when compressed data is acquired.

  As illustrated in FIG. 10, the decompression device 200 acquires compressed data and decompresses the compressed data (step S201). The restoration device 200 adds the difference value for each byte group (step S202), and integrates each byte group (step S203).

  The restoration apparatus 200 integrates the time information and other item information (step S204), and outputs log data (step S205).

  Next, the effect of the compression apparatus 100 according to the present embodiment will be described. The compression apparatus 100 divides the time information of the log data for each predetermined data width, and generates difference value information 140a by taking a difference for each divided data width. For example, since the time information increases by a certain amount, by taking the difference and generating the difference value information 140a, the value of the time information can be handled as a numeric string in which the constant values are arranged. For this reason, log data can be efficiently compressed by compressing the difference value information 140a.

  In addition, since the compression apparatus 100 extracts time information from the log data and compresses the data separately from the information of other items, the information of other items can be efficiently compressed.

  Further, when the decompression apparatus 200 according to the present embodiment acquires compressed data compressed by the compression apparatus 100, the decompression apparatus restores the compressed data, thereby generating a plurality of differential byte groups and adding the differential byte groups. In this way, a byte group is generated. Then, the restoration device 200 generates time information by integrating the byte groups. For this reason, the compressed data compressed by the compression apparatus 100 can be restored appropriately.

  By the way, the difference value calculation unit 130 illustrated in FIG. 1 generates the difference value information by generating the difference value information by taking the difference between the values before and after being included in the byte group. However, the present invention is not limited to this. Is not to be done. For example, the difference value calculation unit 130 may calculate a difference value by comparing a certain value in the byte group with a value a predetermined number before this value.

  FIG. 11 is a diagram for explaining other processing of the difference value calculation unit. In the example shown in FIG. 11, the difference value calculation unit 130 obtains a difference value by comparing with the previous four values. The byte groups 35 a to 38 a in FIG. 11 are byte groups acquired from the byte dividing unit 120.

  Here, as an example, a case where the difference value calculation unit 130 generates the difference byte 35c from the byte group 35a will be described. The difference value calculation unit 130 stores the values of the first t11 to the fourth t41 of the byte group 35a as they are in the first to fourth of the difference byte group 35c. Subsequently, the difference value calculation unit 130 stores a value obtained by subtracting t11 from t51 as the fifth of the difference byte group 35c. Further, the difference value calculation unit 130 stores a value obtained by subtracting t21 from t61 in the sixth of the difference byte group 35c. By sequentially executing such processing, the difference value calculation unit 130 generates a difference byte group 35c from the byte group 35a. Similarly, the difference value calculation unit 130 generates difference byte groups 36c to 38c from the byte groups 36a to 38a.

  Here, an example of the difference byte group obtained from the byte groups 31 to 34 shown in FIG. 4 will be described. FIG. 12 is a diagram (2) illustrating an example of the difference byte group. As illustrated in FIG. 12, the difference value calculation unit 130 generates difference byte groups 45 to 48 by comparing previous and next values for each byte group and taking a difference.

  In this way, the compression apparatus 100 compares a certain value of the byte group with a value that is a predetermined number before this value and calculates a difference value, whereby the value of the time information is changed to a certain value. Can be treated as a line of numbers.

  Note that the compression method of the data compression unit 150 is not limited to LZ77. For example, the LZ78 method or PPM (Prediction by Partial Matching) may be used.

  In FIG. 1, the item dividing unit 110 and the byte dividing unit 120 are examples of dividing units. The difference calculation unit 130 is an example of a difference unit. The data compression unit 150 is an example of a compression unit.

  Next, an example of a computer that executes a compression program that realizes the same function as that of the compression apparatus 100 illustrated in FIG. 1 will be described. FIG. 13 is a diagram illustrating an example of a computer that executes a compression program.

  As illustrated in FIG. 13, the computer 300 includes a CPU 301 that executes various arithmetic processes, an input device 302 that receives input of data from a user, and a display 303. The computer 300 also includes a reading device 304 that reads a program or the like from a storage medium, and an interface device 305 that exchanges data with other computers via a network. The computer 300 also includes a RAM 306 that temporarily stores various types of information and a hard disk device 307. The devices 301 to 307 are connected to the bus 308.

  The hard disk device 307 has a division program 307a, a difference program 307b, and a compression program 307c. The CPU 301 reads each program 307 a to 307 c and develops it in the RAM 306. The division program 307a functions as a division process 306a. The difference program 307b functions as a difference process 306b. The compression program 307c functions as a compression process 306c.

  For example, the division process 306 a corresponds to the byte division unit 120. The difference process 306 b corresponds to the difference value calculation unit 130. The compression process 306 c corresponds to the data compression unit 150.

  Next, an example of a computer that executes a restoration program that implements the same function as that of the restoration apparatus 200 illustrated in FIG. 7 will be described. FIG. 14 is a diagram illustrating an example of a computer that executes a restoration program.

  As illustrated in FIG. 14, the computer 400 includes a CPU 401 that executes various arithmetic processes, an input device 402 that receives input of data from a user, and a display 403. The computer 400 includes a reading device 404 that reads a program and the like from a storage medium, and an interface device 405 that exchanges data with another computer via a network. The computer 400 also includes a RAM 406 that temporarily stores various types of information and a hard disk device 407. The devices 401 to 407 are connected to the bus 408.

  The hard disk device 407 has a restoration program 407a, an addition program 407b, and an integration program 407c. The CPU 401 reads each program 407 a to 407 c and develops it in the RAM 406. The restoration program 407a functions as a restoration process 406a. The addition program 407b functions as an addition process 406b. The integration program 407c functions as an integration process 406c.

  For example, the restoration process 406 a corresponds to the data restoration unit 210. The adding process 406 b corresponds to the adding unit 230. The integration process 406c corresponds to the byte integration unit 240.

  The programs 307a to 307c and 407a to 407c do not necessarily have to be stored in the hard disk devices 307 and 407 from the beginning. For example, each program is stored in a “portable physical medium” such as a flexible disk (FD), a CD-ROM, a DVD disk, a magneto-optical disk, and an IC card inserted into the computers 300 and 400. And you may make it the computer 300,400 read and run each program from these.

  The following supplementary notes are further disclosed with respect to the embodiments including the above examples.

(Supplementary note 1) a dividing unit that divides a plurality of continuous measurement data into predetermined data widths;
By obtaining each measurement data divided by the dividing unit for each predetermined data width and taking a difference for each divided data width of each measurement data, difference data including a difference value for each predetermined data width is obtained. A difference part to be generated;
And a compression unit that compresses each difference value for each predetermined data width included in the difference data.

(Supplementary Note 2) The measurement data includes time data, the dividing unit extracts the time data from the measurement data, divides the time data into predetermined data widths, and the difference unit includes each time data 2. The compression apparatus according to claim 1, wherein difference data including a difference value for each predetermined data width is generated by taking a difference for each divided data width.

(Additional remark 3) The said difference part produces | generates the difference data containing the difference value for every predetermined | prescribed data width by taking a difference for every divided data width of the measurement data before and behind continuous. The compression apparatus according to 1 or 2.

(Additional remark 4) The said difference part is each each of 2nd measurement data of the predetermined number before this 1st measurement data from the value of each data width of 1st measurement data among several continuous measurement data. 3. The compression apparatus according to appendix 1 or 2, wherein difference data including a difference value for each predetermined data width is generated by subtracting the data width value.

(Supplementary Note 5) A compression method executed by a computer,
A plurality of continuous measurement data stored in the storage device is divided for each predetermined data width,
Each measurement data divided for each predetermined data width is acquired, and difference data including a difference value for each predetermined data width is generated by taking a difference for each divided data width of each measurement data,
A compression method comprising: performing each process of compressing a difference value for each predetermined data width included in the difference data.

(Supplementary Note 6) The measurement data includes time data, and the dividing process includes extracting the time data from the measurement data, dividing the time data into predetermined data widths, and generating the difference data. 6. The compression method according to appendix 5, wherein difference data including a difference value for each predetermined data width is generated by taking a difference for each divided data width of each time data.

(Additional remark 7) The process which produces | generates the said difference data produces | generates the difference data containing the difference value for every predetermined | prescribed data width by taking a difference for every divided data width of the measurement data before and behind continuous. The compression method according to appendix 5 or 6, which is characterized.

(Additional remark 8) The process which produces | generates the said difference data is a 2nd of the predetermined number before this 1st measurement data from the value of each data width of 1st measurement data among several continuous measurement data. The compression method according to appendix 5 or 6, wherein difference data including a difference value for each predetermined data width is generated by subtracting the value of each data width of the measurement data.

(Appendix 9)
A plurality of continuous measurement data stored in the storage device is divided for each predetermined data width,
Each measurement data divided for each predetermined data width is acquired, and difference data including a difference value for each predetermined data width is generated by taking a difference for each divided data width of each measurement data,
A compression program that causes each process to compress a difference value for each predetermined data width included in the difference data.

(Supplementary Note 10) The measurement data includes time data, and the dividing process extracts the time data from the measurement data, divides the time data into predetermined data widths, and generates the difference data. 10. The compression program according to appendix 9, wherein difference data including a difference value for each predetermined data width is generated by taking a difference for each divided data width of each time data.

(Additional remark 11) The process which produces | generates the said difference data produces | generates the difference data containing the difference value for every predetermined | prescribed data width by taking a difference for every divided data width of the measurement data before and behind continuous. Item 11. The compression program according to appendix 9 or 10,

(Additional remark 12) The process which produces | generates the said difference data is a 2nd of the predetermined number before this 1st measurement data from the value of each data width of 1st measurement data among several continuous measurement data. The compression program according to appendix 9 or 10, wherein difference data including a difference value for each predetermined data width is generated by subtracting a value of each data width of the measurement data.

(Additional remark 13) The decompression | restoration part which decompress | restores the compressed data compressed for every predetermined data width, and produces | generates the several partial decompression | restoration data of a predetermined data width,
An addition unit that obtains partial restoration data restored by the restoration unit and generates a plurality of addition data by performing addition for each predetermined data width of each partial restoration data;
A restoration apparatus comprising: an integration unit that generates restoration data by integrating a plurality of addition data generated by the addition unit.

100 Compression device 200 Restoration device

Claims (7)

A division unit that divides a plurality of continuous measurement data into predetermined data widths;
By obtaining each measurement data divided by the dividing unit for each predetermined data width and taking a difference for each divided data width of each measurement data, difference data including a difference value for each predetermined data width is obtained. A difference part to be generated;
And a compression unit that compresses each difference value for each predetermined data width included in the difference data.   The measurement data includes time data, the division unit extracts the time data from the measurement data, divides the time data into predetermined data widths, and the difference unit divides each time data. The compression apparatus according to claim 1, wherein difference data including a difference value for each predetermined data width is generated by taking a difference for each data width.   The difference unit generates difference data including a difference value for each predetermined data width by calculating a difference for each divided data width of measurement data before and after the continuous measurement data. The compression apparatus as described in.   The difference unit is configured to calculate a value of each data width of the second measurement data that is a predetermined number before the first measurement data from a value of each data width of the first measurement data among a plurality of continuous measurement data. The compression apparatus according to claim 1, wherein difference data including a difference value for each predetermined data width is generated by subtracting each of the values. A compression method performed by a computer,
A plurality of continuous measurement data stored in the storage device is divided for each predetermined data width,
Each measurement data divided for each predetermined data width is acquired, and difference data including a difference value for each predetermined data width is generated by taking a difference for each divided data width of each measurement data,
A compression method comprising: performing each process of compressing a difference value for each predetermined data width included in the difference data. On the computer,
A plurality of continuous measurement data stored in the storage device is divided for each predetermined data width,
Each measurement data divided for each predetermined data width is acquired, and difference data including a difference value for each predetermined data width is generated by taking a difference for each divided data width of each measurement data,
A compression program that causes each process to compress a difference value for each predetermined data width included in the difference data. A decompression unit that decompresses compressed data compressed for each predetermined data width and generates a plurality of partial decompression data having a predetermined data width;
An addition unit that obtains partial restoration data restored by the restoration unit and generates a plurality of addition data by performing addition for each predetermined data width of each partial restoration data;
A restoration apparatus comprising: an integration unit that generates restoration data by integrating a plurality of addition data generated by the addition unit.

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