JP4446102B2 - Data compression / decompression system, data compression device, data decompression device, and program - Google Patents

Description

  The present invention relates to a data compression / decompression system, a data compression device, a data decompression device, and a program applied to data transmission between computers using different character codes.

  In recent years, with the development of a local area network (LAN), the Internet, etc., it has become common to connect a computer via a network and transmit data. The capacity of data to be transmitted is constantly increasing due to progress in systemization and networking.

  When transmitting a large amount of data via a network, a technique for compressing data is usually used to reduce the load on the network and the time required for data transmission.

  As this type of data compression processing method, there is a method called run-length coding in which when the same character is continuous, a number indicating the number of appearances is written together to reduce the total amount. According to this method, for example, as shown in FIG. 8, the character string “AAAAAAA” is represented by the symbol “A6” meaning “there are six A”, and the character string “BBBB” is represented by “four B By replacing with the sign “B4” meaning “something”, the 10 characters can be changed to 4 characters while maintaining the meaning, and the capacity can be compressed to 2/5. Here, such a compression processing method is referred to as “monocharacter field compression by the run length method”.

  As another data compression processing method, there is a method of compressing overlapping portions between before and after records of a file. In this method, if there is an identical part as compared with the previous record being processed, this is compressed. For example, as shown in FIG. 9, when the first record is “ABCDEF | AAAAAAA | DBCD” and the second record is “ABCDEF | BBBBBBB | HIJK”, “ABCDEF in the second record” "Is the same part as the first record, the part" ABCDEF "in the second record is replaced with compressed data such as" A to F ". Note that “AAAAAAA” in the first record and “BBBBBBB” in the second record are compressed by being replaced with “A6” and “B6”, respectively, as described above. When returning the part replaced with the compressed data such as “A to F” to the original state, the previous duplicated record part, that is, “ABCDEF” is copied, and the copied “ Replace with "ABCDEF".

  Such a compression method is referred to herein as “copy field compression by the run-length method”, and this compression is also interpreted as being included in the run-length method. In the case of simply “run-length method”, mono-character field compression and copy field compression are collectively referred to.

  The compressed data needs to be restored to the original uncompressed data so that it can be used for processing at the receiving computer after transmission. This process is generally called “thawing”, “decompression”, “extension”, “decompression” or “extraction”. That is, when compressed data is transmitted via a network, a compression / transmission / restoration process is performed (see Patent Document 1). This series of processing is applied when data is transmitted between computers having the same character code system.

  On the other hand, when transmitting data between computers with different character code systems, in addition to the series of processes described above, a character code conversion process that converts the data format of the sending computer into a data format that can be recognized by the receiving computer Is required. The processing method includes a technique for converting the data format into a character code that can be recognized by the receiving computer before or after receiving the compressed data (Patent Document 2), and connecting a computer having a character code conversion processing function to the network. However, there is a technique (Patent Document 3) that performs data transmission via the computer.

  As described above, when a large amount of data is transmitted between computers having different character code systems, as shown in FIG. 8, is the process procedure (process procedure 1) of compression-transmission-restore-character code conversion taken? Alternatively, as shown in FIG. 10, the processing procedure (processing procedure 2) of character code conversion-compression-transmission-restoration is performed.

  FIG. 11 is a functional block diagram illustrating an example of a device configuration that realizes the processing procedure 1. The transmission-side computer 50 includes a database 52 that stores data to be transmitted, and compression processing of data stored in the database 52. And a transmission unit 56 for transmitting the data compressed by the compression processing unit 54 to the receiving computer 60. The receiving computer 60 includes a receiving unit 62 that receives data transmitted from the transmitting unit 56, a restoration processing unit 64 that restores data received by the receiving unit 62, and restoration processing performed by the restoration processing unit 64. A character code conversion processing unit 66 that converts the converted data into a character code that can be recognized by the receiving computer 60, and a database 68 that stores data in which the character code is converted by the character code conversion processing unit 66. Yes.

FIG. 12 is a functional block diagram showing an apparatus configuration example for realizing the processing procedure 2. The character code conversion processing unit 66 provided in the receiving computer 60 in FIG. And the compression processing unit 54.
Japanese Examined Patent Publication No. 4-53328 (Detailed Description of the Invention) Japanese Patent No. 2604507 ([0012], FIG. 1, [0003] to [0010], FIG. 3) Japanese Patent No. 3670303 (Claim 1)

  However, in the technique of Patent Document 2, all data is subjected to character code conversion processing before the compressed data is created in the sending computer 50 or after the compressed data is restored in the receiving computer 60. Therefore, when a large amount of data is transmitted, the load on the computer that performs the character code conversion process increases, resulting in a delay in subsequent processing of the computer or other processing.

  On the other hand, in the technique of Patent Document 3, data is transmitted twice between a computer that performs character code conversion processing with a transmitting computer 50 and between a computer that performs character code conversion processing and a receiving computer 60 via a network. Is transmitted. In addition, from the description in this document, it is presumed that the data transmitted between these computers is not compressed.

  Therefore, when a large amount of data is transmitted, the load on the network increases, causing a delay in processing of all computers that transmit data using the network. In addition, even if the data to be transmitted is compressed, the increase in network load due to data transmission twice is inevitable, and data that has not been compressed is transmitted to some extent. The same result as in the case of doing so will be brought about.

  The present invention has been made in view of such circumstances, and reduces the load on a computer that performs character code conversion processing when data compressed by the run length method is transmitted between computers having different character code systems. A data compression / decompression system, a data compression device, a data decompression device, and a program capable of preventing a delay in subsequent processing in the computer and thereby improving the efficiency of the entire processing using the computer. The purpose is to provide.

  In order to achieve the above object, the present invention takes the following measures.

  That is, the invention of claim 1 is a data compression / decompression system comprising a transmitting computer and a receiving computer, and compression means for compressing data to be transmitted to the transmitting computer by a run length method. And transmitting means for transmitting the data compressed by the compressing means to the receiving computer. A receiving unit that receives the data transmitted by the transmitting unit; a converting unit that converts the data format of the data received by the receiving unit into a data format that can be recognized by the receiving computer; A restoring means for restoring a portion compressed by the run length method from the data whose data format has been converted by the means;

  The invention of claim 2 is the data compression / decompression system of the invention of claim 1, wherein the data to be transmitted is composed of a plurality of records, and compression is performed when at least two consecutive records include the same part. The means compresses the same portion included in records other than the first record among consecutive records. Further, the overwriting means for overwriting the portion corresponding to the same portion of the data whose data format has been converted by the converting portion with the copy of the portion corresponding to the same portion converted in the first record in the receiving computer. Is provided.

  A third aspect of the present invention is a data compression apparatus that is applied to a data compression / decompression system composed of a transmission-side computer and a reception-side computer, and that is provided in the transmission-side computer. And a transmission means for transmitting the data compressed by the compression means to the receiving computer. The transmitted data is received by the receiving computer and converted into a data format recognizable by the receiving computer, and then the portion compressed by the run length method is restored.

  According to a fourth aspect of the present invention, in the data compression apparatus of the third aspect of the present invention, when the data to be transmitted is composed of a plurality of records and the same portion is included in at least two consecutive records, the compression means is Compress the same part included in records other than the first record among consecutive records. In the transmitted data, the portion corresponding to the same portion of the data whose data format has been converted is overwritten with a copy of the portion corresponding to the same portion converted in the first record.

  The invention of claim 5 is a data decompression apparatus applied to a data compression / decompression system comprising a transmitting computer and a receiving computer, and is provided in the receiving computer, wherein the run-length method is used by the transmitting computer. Receiving means for receiving the data compressed by the receiving means and then transmitted to the receiving computer, and converting means for converting the data format of the data received by the receiving means into a data format that can be recognized by the receiving computer; And a restoring means for restoring a portion compressed by the run length method from the data whose data format has been converted by the converting means.

  According to a sixth aspect of the present invention, in the data restoration device according to the fifth aspect, when the data to be transmitted is composed of a plurality of records and the same part is included in at least two consecutive records, the receiving means In the received data, the same part included in records other than the first record is compressed among consecutive records. The data further converted by the converting means is further provided with overwriting means for overwriting a portion corresponding to the same portion with a copy of the portion corresponding to the same portion converted in the first record.

  A seventh aspect of the present invention is a data compression / decompression system comprising a transmitting computer and a receiving computer, the compression means for compressing data to be transmitted to the transmitting computer by a run length method, and compression Conversion means for converting the data format of the data compressed by the means into a data format that can be recognized by the receiving computer, and transmitting means for transmitting the data whose data format has been converted to the receiving computer. Yes. The receiving computer includes receiving means for receiving the data transmitted by the transmitting means, and restoring means for restoring a portion compressed by the run-length method from the data received by the receiving means.

  The invention according to claim 8 is the data compression / decompression system according to claim 7, wherein the data to be transmitted is composed of a plurality of records, and compression is performed when the same part is included in at least two consecutive records. The means compresses the same portion included in records other than the first record among consecutive records. Further, the data corresponding to the same part of the data received by the receiving means after the data format is converted by the converting means is converted into the part corresponding to the same part converted in the first record. An overwriting means is provided for overwriting with a copy.

  A ninth aspect of the present invention is a data compression apparatus that is applied to a data compression / decompression system including a transmission-side computer and a reception-side computer, and that is provided in the transmission-side computer. The compression means for compressing the data, the conversion means for converting the data format of the data compressed by the compression means into a data format that can be recognized by the receiving computer, and the data whose data format has been converted to the receiving computer Transmitting means for transmitting. The transmitted data is received by the receiving computer, and the portion compressed by the run length method is restored.

  According to a tenth aspect of the present invention, in the data compression apparatus according to the ninth aspect, when the data to be transmitted is composed of a plurality of records and the same portion is included in at least two consecutive records, the compression means includes: Compress the same part included in the records other than the first record among the consecutive records, and the transmitted data is the data corresponding to the same part of the converted data in the first record. Overwritten with a copy of the part corresponding to the same converted part.

  The invention of claim 11 is a data decompression apparatus applied to a data compression / decompression system comprising a transmitting computer and a receiving computer, and is provided in the receiving computer. The data format of the compressed and compressed data is converted into a data format that can be recognized by the receiving computer, and then received by the receiving device and received by the receiving device. And a restoring means for restoring a portion compressed by the run length method.

  According to a twelfth aspect of the present invention, in the data restoration apparatus of the eleventh aspect, when the data to be transmitted consists of a plurality of records and the same portion is included in at least two consecutive records, the receiving means In the received data, the same part included in records other than the first record is compressed among consecutive records. The data processing apparatus further includes overwriting means for overwriting a portion corresponding to the same portion of the data received by the receiving means with a copy of the portion corresponding to the same portion converted in the first record.

  A thirteenth aspect of the invention is a data compression / decompression program applied to a data compression / decompression system composed of a transmitting computer and a receiving computer, and a function for compressing transmitted data by a run-length method. A data compression program for causing a transmitting computer to realize a function of transmitting compressed data to a receiving computer, a function of receiving transmitted data, and a data format of the received data And a data restoration program for causing the receiving computer to realize a function of restoring a portion compressed by the run length method among the data converted into the data format.

  According to a fourteenth aspect of the present invention, in the data compression / decompression program according to the thirteenth aspect of the present invention, the data compression program comprises a plurality of records to be transmitted, and the same portion is included in at least two consecutive records. In this case, the transmitting computer is further provided with a function of compressing the same portion included in the records other than the first record among the consecutive records. The data restoration program further has a function of overwriting the portion corresponding to the same portion of the data whose data format has been converted with a copy of the portion corresponding to the same portion converted in the first record in the receiving computer. make it happen.

  A fifteenth aspect of the present invention is a data compression / decompression program applied to a data compression / decompression system composed of a transmission-side computer and a reception-side computer, and a function for compressing transmitted data by a run-length method In order for the transmitting computer to realize the function of converting the data format of the compressed data into a data format that can be recognized by the receiving computer, and the function of transmitting the data whose data format has been converted to the receiving computer Data receiving program, a function for receiving transmitted data, and a data restoring program for causing a receiving computer to realize a function for restoring a portion of the received data compressed by the run-length method.

  According to a sixteenth aspect of the present invention, in the data compression / decompression program according to the fifteenth aspect of the present invention, the data compression program includes a plurality of records to be transmitted, and the same portion is included in at least two consecutive records. In this case, the transmitting computer is further provided with a function of compressing the same portion included in the records other than the first record among the consecutive records. The data restoration program further has a function of overwriting a portion corresponding to the same portion of the data received after the data format is converted with a copy of the portion corresponding to the same portion converted in the first record. Implement on the receiving computer.

  The invention of claim 17 is a data compression program in the data compression / decompression program of any one of claims 13 to 16.

  The invention of claim 18 is a data restoration program in the data compression / decompression program of any one of claims 13 to 16.

  According to the present invention, when data compressed by the run length method is transmitted between computers having different character code systems, the load of the computer that performs character code conversion processing is reduced, thereby reducing the subsequent processing in the computer. Delay can be prevented.

  As described above, the data compression / decompression system, the data compression device, the data decompression device, and the program that can improve the efficiency of the entire processing using the computer can be realized.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is a functional block diagram illustrating a configuration example of a data compression / decompression system according to the first embodiment.

  That is, the data compression / decompression system according to the present embodiment includes a transmission-side computer 10 that operates as a data compression device with a data compression program installed therein, and a reception-side computer that operates as a data decompression device with a data recovery program installed. 20 is a data compression / decompression system.

  The transmitting computer 10 includes a database 12 made of hardware such as a hard disk for storing data to be transmitted. Further, the data compression program retrieves data to be transmitted from the database 12, compresses the retrieved data by the run-length method, and directs the data compressed by the compression processor 14 to the receiving computer 20. A transmission unit 16 for transmission is constructed.

  As shown in FIG. 2, the compression processing unit 14 includes a plurality of records, and when the same part is included in at least two consecutive records, in addition to the above compression, Of the consecutive records, compress the same part included in the records other than the first record. In the case of FIG. 2, the transmitted data consists of two records, and the first record and the second record that are continuous contain the same part “ABCDEF”, so other than the first record The same part “ABCDEF” included in the second record, which is a record of “”, is compressed as “A to F”.

  The receiving computer 20 can recognize the receiving unit 22 that receives the data transmitted by the transmitting unit 16 and the data format of the data received by the receiving unit 22 by the data restoring program. A character code conversion processing unit 24 for converting to a simple data format, a restoration processing unit 26 for restoring a portion compressed by the run length method from the data whose data format has been converted by the character code conversion processing unit 24, and a copy process Part 28 is constructed. Further, a database 30 made of hardware such as a hard disk for storing data restored by the restoration processing unit 26 or the copy processing unit 28 is provided.

  When the data to be transmitted consists of a plurality of records and the same part is included in at least two consecutive records, the copy processing unit 28 uses the compression processing unit 14 to select a record other than the first record among the consecutive records. When the same part included in the record is compressed, the part corresponding to the same part of the data whose data format has been converted by the character code conversion processing unit 24 is changed to the same part converted in the first record. Overwrite with a copy of the corresponding part. For example, when compression such as “A to F” shown in FIG. 2 is performed by the compression processing unit 14, among the data whose data format is converted by the character code conversion processing unit 24, 2 shown in FIG. The portion of “A to F” corresponding to “A to F” of the record of the case is overwritten with a copy of the portion “Aioka” corresponding to the same portion converted in the first record.

  The data compression program and the data restoration program described above are not limited to being distributed to the transmission side computer 10 and the reception side computer 20 via a network. For example, a magnetic disk (floppy (registered trademark) disk, hard disk, etc.) It can also be stored and distributed in a recording medium such as an optical disk (CD-ROM, DVD, etc.), semiconductor memory or the like. The program stored in the recording medium includes not only an execution program to be executed by the transmission side computer 10 and the reception side computer 20 but also a program that can include a table and a data structure in the transmission side computer 10 and the reception side computer 20. Also includes a configuration program to be configured.

  Next, the operation of the data compression / decompression system according to the present embodiment configured as described above will be described using the flowchart shown in FIG.

  That is, when data is transmitted from the sending computer 10 to the receiving computer 20 by the data compression / decompression system according to the present embodiment, first, in the sending computer 10, the data to be transmitted is stored in the database by the compression processing unit 14. 12 is taken out (S1).

  For example, as shown in FIG. 2, the retrieved data includes a first record consisting of “ABCDEF | AAAAAAA | DBCD” and a second record consisting of “ABCDEF | BBBB | HIJK”. To do.

  The extracted data is compressed by the run length method by the compression processing unit 14. That is, “AAAAAAA” in the first record is compressed to “A6”, and “BBBB” in the second record is changed to “B4”.

  In the case of FIG. 2, the transmitted data is composed of two records, and the first record and the second record contain the same part “ABCDEF”. The included portion “ABCDEF” is changed to “A to F” to be compressed (S2). When such a record does not exist, compression is not performed so that “ABCDEF” is changed to “A to F”, and compressed data as shown in FIG. 4 is obtained.

  The data compressed by the compression processing unit 14 in this way is transmitted to the receiving computer 20 by the transmission unit 16 (S3).

  The transmitted data is received by the receiving unit 22 of the receiving computer 20 (S4).

  Further, the data received by the receiving unit 22 is converted into a data format that can be recognized by the receiving computer 20 by the character code conversion processing unit 24 (S5). For example, as shown in FIG. 2, the first record “ABCDEF | A6 | DBCD” of the data received by the receiving unit 22 is “Aiueoka |” which is a data format that can be recognized by the receiving computer 20. The second record “A to F | B4 | HIJK” is converted to “A6 | Ei4”, which is a data format that can be recognized by the receiving computer 20. Converted.

  Next, of the data whose data format has been converted by the character code conversion processing unit 24, the portion compressed by the run length method is restored by the restoration processing unit 26 (S6). For example, as shown in FIG. 2, in the first record, the portion “A 6” compressed by the run length method is compressed to “Oh ah ah”, and the second record is compressed by the run length method. The location “I4” is restored to “Good”.

  Further, the compression processing unit when the transmitted data is composed of a plurality of records among the data whose data format is converted by the character code conversion processing unit 24 and the same part is included in at least two consecutive records. 14, when the same part included in the record other than the first record is compressed among the consecutive records, the part corresponding to the same part is converted in the first record by the copy processing unit 28. It is overwritten with a copy of the part corresponding to the part (S7). For example, as shown in FIG. 2, when the compression processing unit 14 compresses the second record such as “A to F”, the character code conversion processing unit 24 converts the data format. Of the converted data, the portion corresponding to “A to F” of the second record is the portion corresponding to the same portion converted “Aueo” in the first record. Is overwritten with a copy of

  The order of the process of step S6 performed by the restoration processing unit 26 and the process of step S7 performed by the copy processing unit 28 can be exchanged. Note that when the compression processing unit 14 does not perform compression to change “ABCDEF” to “A to F”, only the process of step S6 performed by the restoration processing unit 26 is performed as shown in FIG. Is called.

  Through such a series of processes, the data transmitted from the transmitting computer 10 is recognized by the receiving computer 20. This data is stored in the database 30 (S8).

  As described above, in the data compression / decompression system according to the present embodiment, when data compressed by the run length method is transmitted between computers having different character code systems, the receiving side In the computer 20, the received compressed data is converted into a character code that can be recognized by the receiving computer 20, and then restored or further overwritten. Therefore, compared with the prior art in which character code conversion processing is performed after restoration or further overwriting. Thus, the processing amount of character code conversion can be reduced, and the load on the receiving computer 20 can be reduced.

  In order to show this quantitative effect, the conventional technology and the present embodiment are targeted for 70,000 pieces of data having a record length of 6000 bytes (file size before compression: 420 MB, file size after compression: 35 MB). When the time required for the entire processing is compared with the data compression / decompression system according to the present invention, the conventional technique requires 40-50 seconds, but the data compression / decompression system according to the present embodiment requires 8-12 seconds. However, the result was that the processing speed was about 3 to 6 times faster.

  As described above, in the data compression / decompression system according to the present embodiment, the time required for the entire processing can be suppressed to about 1/6 to 1/3 as compared with the prior art, and the load on the receiving computer 20 is reduced. Thus, not only can the delay of subsequent processing performed by the receiving computer 20 be prevented, but also the processing efficiency of the entire data compression / decompression system can be improved. Become.

(Second Embodiment)
The data compression / decompression system according to the second embodiment of the present invention is a modification of the data compression / decompression system according to the first embodiment. Therefore, here, the same parts are denoted by the same reference numerals to avoid redundant description, and different points will be described.

  FIG. 5 is a functional block diagram illustrating a configuration example of the data compression / decompression system according to the second embodiment.

  That is, in the data compression / decompression system according to the present embodiment, in the data compression / decompression system according to the first embodiment, the character code conversion processing unit 24 provided in the reception-side computer 20 is replaced with the transmission-side computer. 10 is provided between the compression processing unit 14 and the transmission unit 16.

  Therefore, as shown in FIG. 6 and FIG. 7, from the transmission unit 16 of the transmission side computer 10, the compressed data converted into a character code that can be recognized by the reception side computer 20 by the character code conversion processing unit 24 is received. It is transmitted to the computer 20.

  In addition to the compression by the run length method in which “AAAAAAA” is set to “A6”, FIG. 6 shows that the transmitted data is composed of a plurality of records, and at least two consecutive records include the same part. FIG. 6 is a diagram showing a flow of data processing when the same part included in a record other than the first record among the consecutive records is compressed by the compression processing unit 14.

  On the other hand, FIG. 7 shows that the data to be transmitted is composed of a plurality of records, and at least two consecutive records do not contain the same portion, and only compression by the run length method in which “AAAAAAA” is set to “A6”. It is a figure which shows the flow of the data processing in the case where is made.

  Like the data compression / decompression system according to the present embodiment, the character code conversion processing unit 24 provided in the reception-side computer 20 in the data compression / decompression system according to the first embodiment is replaced with the transmission-side computer 10. When the data compressed by the run-length method is transmitted between computers having different character code systems, the transmitting computer 10 performs compression. Since the processed data is converted into a character code that can be recognized by the receiving computer 20, it is possible to reduce the processing amount of the character code conversion compared to the conventional technique in which the character code conversion processing is performed before the compression processing. Thus, the load on the transmitting computer 10 can be reduced.

  In order to show this quantitative effect, the conventional technology and the present embodiment are targeted for 70,000 pieces of data having a record length of 6000 bytes (file size before compression: 420 MB, file size after compression: 35 MB). When the time required for the entire processing is compared with the data compression / decompression system according to the present invention, the conventional technique requires 40-50 seconds, but the data compression / decompression system according to the present embodiment requires 8-12 seconds. However, the result was that the processing speed was about 3 to 6 times faster.

  As described above, in the data compression / decompression system according to the present embodiment, the time required for the entire processing can be suppressed to about 1/6 to 1/3 as compared with the prior art, and the load on the transmitting computer 10 is reduced. Therefore, not only can the delay of the subsequent processing performed by the transmitting computer 10 be prevented, but also the processing efficiency of the entire data compression / decompression system can be improved. Become.

  The best mode for carrying out the present invention has been described above with reference to the accompanying drawings, but the present invention is not limited to such a configuration. Within the scope of the invented technical idea of the scope of claims, a person skilled in the art can conceive of various changes and modifications. The technical scope of the present invention is also applicable to these changes and modifications. It is understood that it belongs to.

The functional block diagram which shows the structural example of the data compression / decompression system which concerns on 1st Embodiment. The figure which shows an example of the compression process in the data compression / decompression system which concerns on 1st Embodiment, a transmission process, a character code conversion process, and a decompression | restoration process. 3 is a flowchart showing the operation of the data compression / decompression system according to the first embodiment. The figure which shows another example of the compression process in the data compression / decompression system which concerns on 1st Embodiment, a transmission process, a character code conversion process, and a decompression | restoration process. The functional block diagram which shows the structural example of the data compression / decompression system which concerns on 2nd Embodiment. The figure which shows an example of the compression process in the data compression / decompression system which concerns on 2nd Embodiment, a character code conversion process, a transmission process, and a decompression | restoration process. The figure which shows another example of the compression process in the data compression / decompression system which concerns on 2nd Embodiment, a character code conversion process, a transmission process, and a decompression | restoration process. The figure which shows an example of the compression process in the data compression / decompression system in a prior art, a transmission process, a decompression | restoration process, and a character code conversion process (process procedure 1). The figure which shows the example of the data in which the same part is contained in the 1st record and the 2nd record. The figure which shows an example of the character code conversion process in a data compression / decompression system in a prior art, a compression process, a transmission process, and a decompression | restoration process (processing procedure 2). The functional block diagram which shows the apparatus structural example which implement | achieves the process procedure 1 in a prior art. The functional block diagram which shows the example of an apparatus structure which implement | achieves the process procedure 2 in a prior art.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Transmission side computer, 12 ... Database, 14 ... Compression processing part, 16 ... Transmission part, 20 ... Reception side computer, 22 ... Reception part, 24 ... Character code conversion processing part, 26 ... Restoration processing part, 28 ... Copy processing , 30 ... database, 50 ... transmitting computer, 52 ... database, 54 ... compression processing unit, 56 ... transmitting unit, 60 ... receiving computer, 62 ... receiving unit, 64 ... restoration processing unit, 66 ... character code conversion processing Department, 68 ... Database

Claims (18)

A data compression / decompression system comprising a sending computer and a receiving computer,
In the sending computer,
A compression means for compressing data to be transmitted by a run length method;
Transmission means for transmitting the data compressed by the compression means to the receiving computer,
In the receiving computer,
Receiving means for receiving data transmitted by the transmitting means;
Converting means for converting the data format of the data received by the receiving means into a data format recognizable by the receiving computer;
A data compression / decompression system comprising decompression means for restoring a portion compressed by the run-length method from among the data whose data format has been converted by the conversion means. The data compression / decompression system according to claim 1,
When the transmitted data consists of a plurality of records and the same part is included in at least two consecutive records, the compression means includes the records other than the first record among the consecutive records. Compress the same part
In addition to the receiving computer,
Data comprising overwriting means for overwriting a portion corresponding to the same portion of the data whose data format has been converted by the converting portion with a copy of the portion corresponding to the same portion converted in the first record. Compression / decompression system. A data compression apparatus that is applied to a data compression / decompression system composed of a transmission-side computer and a reception-side computer and is provided in the transmission-side computer,
A compression means for compressing data to be transmitted by a run length method;
Transmission means for transmitting the data compressed by the compression means to the receiving computer,
Data compression in which the transmitted data is received by the receiving computer and converted into a data format recognizable by the receiving computer, and then the portion compressed by the run length method is restored. apparatus. The data compression apparatus according to claim 3, wherein
When the transmitted data consists of a plurality of records and the same part is included in at least two consecutive records, the compression means includes the records other than the first record among the consecutive records. Compress the same part
The transmitted data is a data compression in which the portion corresponding to the same portion of the data whose data format has been converted is overwritten with a copy of the portion corresponding to the same portion converted in the first record. apparatus. A data decompression apparatus that is applied to a data compression / decompression system composed of a sending computer and a receiving computer, and is provided in the receiving computer,
Receiving means for receiving the data compressed by the transmission side computer by the run length method and then transmitted to the receiving side computer;
Converting means for converting the data format of the data received by the receiving means into a data format recognizable by the receiving computer;
A data restoration apparatus comprising restoration means for restoring a portion compressed by the run-length method from among the data whose data format has been converted by the conversion means. The data restoration device according to claim 5, wherein
When the transmitted data is composed of a plurality of records and the same part is included in at least two consecutive records, the data received by the receiving means is the first record among the consecutive records. The same part included in the record other than is compressed,
Overwriting means for overwriting the portion corresponding to the same portion of the data whose data format has been converted by the converting portion with a copy of the portion corresponding to the same portion converted in the first record. Data restoration device. A data compression / decompression system comprising a sending computer and a receiving computer,
In the sending computer,
A compression means for compressing data to be transmitted by a run length method;
Conversion means for converting the data format of the data compressed by the compression means into a data format recognizable by the receiving computer;
Transmission means for transmitting the data whose data format has been converted to the receiving computer,
In the receiving computer,
Receiving means for receiving data transmitted by the transmitting means;
A data compression / decompression system comprising decompression means for restoring a portion compressed by the run-length method from the data received by the reception means. The data compression / decompression system according to claim 7,
When the transmitted data consists of a plurality of records and the same part is included in at least two consecutive records, the compression means includes the records other than the first record among the consecutive records. Compress the same part
In addition to the receiving computer,
Of the data received by the receiving means after the data format is converted by the converting means, the part corresponding to the same part is overwritten with a copy of the part corresponding to the same part converted in the first record. A data compression / decompression system comprising overwriting means for performing A data compression apparatus that is applied to a data compression / decompression system composed of a transmission-side computer and a reception-side computer and is provided in the transmission-side computer,
A compression means for compressing data to be transmitted by a run length method;
Conversion means for converting the data format of the data compressed by the compression means into a data format recognizable by the receiving computer;
Transmission means for transmitting the data whose data format has been converted to the receiving computer,
A data compression apparatus in which the transmitted data is received by the receiving computer and a portion compressed by the run-length method is restored. The data compression apparatus according to claim 9, wherein
When the transmitted data consists of a plurality of records and the same part is included in at least two consecutive records, the compression means includes the records other than the first record among the consecutive records. Compress the same part
The transmitted data is a data compression in which the portion corresponding to the same portion of the data whose data format has been converted is overwritten with a copy of the portion corresponding to the same portion converted in the first record. apparatus. A data decompression apparatus that is applied to a data compression / decompression system composed of a sending computer and a receiving computer, and is provided in the receiving computer,
Data compressed by the run-side method by the sending computer, the data format of the compressed data is converted into a data format that can be recognized by the receiving computer, and then sent to the receiving computer Receiving means for receiving
A data restoration apparatus comprising: restoration means for restoring a portion compressed by the run length method from the data received by the reception means. The data restoration device according to claim 11, wherein
When the transmitted data is composed of a plurality of records and the same part is included in at least two consecutive records, the data received by the receiving means is the first record among the consecutive records. The same part included in the record other than is compressed,
A data restoration apparatus further comprising overwriting means for overwriting a portion corresponding to the same portion of the data received by the receiving portion with a copy of the portion corresponding to the same portion converted in the first record. . A data compression / decompression program applied to a data compression / decompression system composed of a sending computer and a receiving computer,
A function that compresses transmitted data by the run-length method,
A data compression program for causing the transmitting computer to realize a function of transmitting the compressed data to the receiving computer;
A function of receiving the transmitted data;
A function of converting the data format of the received data into a data format recognizable by the receiving computer;
A data compression / decompression program comprising a data decompression program for causing the receiving computer to realize a function of decompressing a portion compressed by the run length method in the data whose data format has been converted. The data compression / decompression program according to claim 13,
The data compression program is:
When the transmitted data is composed of a plurality of records and the same portion is included in at least two consecutive records, the same portion included in a record other than the first record is included in the consecutive records. Further causing the transmitting computer to perform the compression function,
The data restoration program is
The receiving computer is further realized with a function of overwriting the portion corresponding to the same portion of the data whose data format has been converted with a copy of the portion corresponding to the same portion converted in the first record. Data compression / decompression program. A data compression / decompression program applied to a data compression / decompression system composed of a sending computer and a receiving computer,
A function that compresses transmitted data by the run-length method,
A function of converting the data format of the compressed data into a data format recognizable by the receiving computer;
A data compression program for causing the transmitting computer to realize a function of transmitting the data whose data format has been converted to the receiving computer;
A function of receiving the transmitted data;
A data compression / decompression program comprising a data decompression program for causing the receiving computer to realize a function of decompressing a portion compressed by the run-length method in the received data. The data compression / decompression program according to claim 15,
The data compression program is:
When the transmitted data is composed of a plurality of records and the same part is included in at least two consecutive records, the same part included in the record other than the first record is included in the consecutive records. Further causing the transmitting computer to perform the compression function,
The data restoration program is
The receiving side further has a function of overwriting a portion corresponding to the same portion of the data received after the data format is converted with a copy of the portion corresponding to the same portion converted in the first record. A data compression / decompression program to be realized by a computer.   The data compression program in the data compression / decompression program according to any one of claims 13 to 16.   The data decompression program in the data compression / decompression program according to any one of claims 13 to 16.

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