JP2837006B2 - Text compression device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a word processor and a text compression apparatus for digitized books.

[0002]

2. Description of the Related Art A conventional text compression apparatus registers a plurality of identical character strings in a dictionary in units of words or character strings having a fixed number of characters, and identifies the character strings registered in the dictionary. A text compression method is used in which the same character string in the text is replaced by a code to compress the text.

FIG. 9 shows the structure of a dictionary for registering character strings in word units used in the above-mentioned conventional text compression apparatus.

In a conventional text compression apparatus using the dictionary shown in FIG. 9, for example, a text such as "I use elemental magic that uses the power of wind" [Word 01411] and [Word 12959] are used. "

[0005] [Word 01411], [Word 1
2959] and the like indicate coded words. The original character string can be restored by searching the dictionary of FIG. 9 using the word numbers included in the code.

[0006]

However, in the conventional text compression apparatus described above, the character string registered in the dictionary is 2 characters.
If the number exceeds 56, 2 bytes are required as the identification code. However, many Chinese characters are formed of two characters, and the target word is only a few characters long. Therefore, there is a problem that the compression rate of the entire sentence cannot be increased.

The present invention has been made in view of the above-described problems of the conventional text compression apparatus, and provides a text compression apparatus capable of expanding a text compression ratio by coding a character string.

[0008]

According to the present invention, there is provided a registration means for registering a specific character string among similar character strings from a sentence including a plurality of identical or similar character strings formed from a plurality of words; The identification data of the specific character string registered in the registration means and the similar character string in the sentence which is connected to the registration means, and the starting position and deletion of the character string to be deleted from the specific character string
Character string to be inserted instead of the number of characters to be deleted and the character string to be deleted
You and a conversion means for replacing the differential data, including the door
The start position is equal to or less than the first predetermined number from the start of the specific character string.
The specified character string is divided so that
This is achieved by a text compression device configured to adjust to be within a predetermined number of 2 .

[0009]

In the text compression apparatus according to the present invention, the registration means registers a specific character string among similar character strings from a text including a plurality of identical or similar character strings formed from a plurality of words, and converts the character string. Is connected to the registration means, and the identification data of the specific character string registered in the registration means for a similar character string in the text and the head position of the character string to be deleted from the specific character string
To be inserted instead of the number of characters to be deleted and the character string to be deleted
Replace with the difference data including the character string . The specific string is
The beginning of the string to be deleted is from the beginning of the specific string
It is divided so as to be within the first predetermined number, and the number of deleted characters is
The adjustment is performed so as to be within the second predetermined number.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of a text compression apparatus according to the present invention.

FIG. 1 is a block diagram showing the configuration of an embodiment of a text compression apparatus according to the present invention.

The text compression apparatus shown in FIG. 1 is a control unit 11 which is a part of a conversion means for controlling the recovery of compressed text data and the display of a character string, and is connected to the control unit 11 to recover the text. And a display unit 13 such as a cathode ray tube (CRT) or a liquid crystal display (LCD), which is connected to the control unit 11 and displays the restored text. One of the registering means for storing a character string to be restored from data obtained by compressing the same character string in a long character string by compressing (see FIG. 2) (hereinafter, referred to as a sentence code). And a dictionary 15 which is connected to the control unit 11 and is a part of the registration means for storing the character string restored from the word code, and which is connected to the control unit 11 and uses the sentence code. A part of the conversion means that organically combines and compiles coded sentences compressed with difference data A buffer 17 which is connected to a certain database 16 and the control unit 11 and is a part of a conversion means for storing finally restored results, and a character string which is connected to the control unit 11 and extracted from the dictionary 14 Buffer 18, which is part of conversion means for temporarily storing data, and which is connected to the control unit 11, is constituted by buffers 17, 18 and a memory 19 which is part of conversion means for storing character positions of compressed data. ing.

Next, the above components will be described.

The control unit 11 controls the restoration of compressed text data and the display of character strings, and also controls the operation of other parts.

The input unit 12 is composed of a keyboard for designating a sentence to be restored.

The display unit 13 includes a cathode ray tube (CRT), a liquid crystal display (LCD), and the like so as to display the restored text.

As shown in FIG. 3, the dictionary 14 comprises an index 141 corresponding to a sentence number on a one-to-one basis and a main body 142 for storing variable-length character strings.

The index 141 indicates the head of the corresponding character string in the main body 142, and is configured so that the length of the character string can be determined from the difference from the character position indicated by the next element of the index 141.

The dictionary 15 stores a word number and a 1 as shown in FIG.
The structure corresponds to one to one, and the database 16
It is configured such that sentences coded and compressed by the sentence code and the difference data are organically combined and collected, and a necessary part can be extracted by an instruction of the input unit 12.

The buffer 17 is configured to store the finally restored result, and the buffer 18 is configured to temporarily store the character string extracted from the dictionary 14.

The memory 19 has a pointer 191 indicating the processing position of the text database 16, a pointer 192 indicating the end position of the restoration buffer 17, a pointer 193 indicating the end position of the restoration buffer 18, and an insertion position of the restoration buffer 18. Pointer to
194.

FIG. 2 shows a part of the original sentence compressed by the sentence compression apparatus of the present embodiment. FIG. 3 shows an example of the configuration of a dictionary in which long character strings are registered in the text compression apparatus according to the present embodiment. FIG. 4 shows how a long text string is encoded by the text compression apparatus according to the present embodiment. An example is shown below.

The text compression apparatus according to the present embodiment registers a long character string such as a sentence, a clause or a phrase in the dictionary 14 and codes the same character string (sentence code). If the character string does not completely match the character string registered in the dictionary 14, the difference data is added. That is, the text compression apparatus of the present embodiment uses a text compression method of compressing the original text as shown in FIG. 2 into the form shown in FIG. 4 using the dictionary shown in FIG.

Next, each part of the text of FIG. 4 compressed by the text compression apparatus of FIG. 1 will be described in detail.

[Sentence] in FIG. 4 is a separator for separating the sentence code and the difference data from the ordinary character code. [00023] in FIG. 4 shows a sentence code.
If the dictionary of FIG. 3 is searched with the sentence number included in the code, the original character string is restored.

[01-04] In FIG. 4, [01-04] is deletion data from the character string restored from the sentence code. The number placed after the hyphen indicates the start position of the deletion character. The number placed before is the number of characters to be deleted.
Difference data is constituted by the deleted character data and the inserted character string following the deleted character data.

FIG. 5 is a schematic diagram showing an example in which both a long character string and a character string in word units are coded in the text compression apparatus according to the present embodiment. FIG. 4 is a diagram for explaining a code data structure in the text compression device.

The contents shown in FIG. 5 are obtained by further compressing the latter half of FIG. 4 using the word dictionary of FIG. Note that, as an actual code, a character is usually represented by 2 bytes (most significant byte (MSB) “0”) using a JIS kanji code, and other compressed codes are shown in FIG. The configuration is as shown. To accommodate this structure, if the difference is 256 characters or less from the beginning, the sentence to be registered is divided and adjusted to 255 characters or less, and if the difference is 8 characters or more, it is adjusted to 7 characters or less. I do.

Next, with reference to the flowcharts of FIGS. 7 and 8, the operation of the text compression apparatus of FIG. 1, in particular, the procedure of restoring a compressed document specified by the input unit 12 (see FIG. 1). Will be described.

Taking the first line of the sentence of FIG. 5, first,
With the pointer 191 pointing to the head of the specified compressed data, the pointer 192 is set to the head of the buffer 17 and the pointer 193
Is initialized to point to the head of the buffer 18 (step S1), the type of data pointed to by the pointer 191 is determined (step S2), and in the case of FIG. 5, a separator [statement] comes. The process proceeds to step S3. From here, the subroutine shown in FIG. 8 for restoring the sentence code data is entered.

Since there is a sentence code immediately after the sentence separator, the sentence number [00023] is extracted (step S3).
1) The dictionary 42 through the index 41 with this sentence number
And finds a character string "against the wind ..." (step S32). The found character string is copied to the beginning of the buffer 18 so that the end position is indicated by the pointer 193 (step S33). The pointer 191 is advanced next (step S34), and the type of data indicated by the pointer 191 is determined (step S35). In this case, since the next data is the deleted character data [01-04], the process proceeds to step S36.

The character position and character length to be deleted are extracted from the buffer 18 and the character position is stored in the pointer 194 (step S36). In this case, only the fourth character from the top (the character to be deleted) (in this case,
“Wind”)) is deleted from the buffer 18, the pointer 193 is operated so as to point to the end of the character string (step S37), and the process returns to step S34 to determine the next data in step S35.
Since the character is the normal character "he", the process proceeds to step S39.

This character is inserted into the buffer 18 at the position indicated by the pointer 194, and the pointer 193 and the pointer 194 are advanced by the number of inserted characters so as to point to the end position and the next insertion position, respectively (step S39). Looping S35 and step S39, "ra",
After "ha" is similarly inserted, the next data is the word code [word 08394] by the discrimination in step S35, and the flow advances to step S38.

The dictionary 15 is searched from the word number of the word code, and a corresponding character string, in this case, "earth" is extracted (step S38). The “ground” extracted in step S39 is inserted into the buffer 18, and the process returns to step S34.

In step S35, since it is found that the next data is a sentence separator, the process returns to the main routine of FIG.

Character string (character string prepared in buffer 18)
At the position indicated by the pointer 192 of the buffer 17.

The pointer 193 is pointed to the beginning of the buffer 18 (step S5), the pointer 191 is advanced (step S6), and the end of the data is determined (step S5).
7). In this case, since the data has been completed, the process proceeds to step S8, where the character string stored in the buffer 17 is displayed on the display unit 13 and the process is terminated (step S8).

Next, the third line of the sentence in FIG. 5 will be described.

First, after the initialization of step S1 is performed in the same manner as in the first line, the first character is the ordinary character "ta" in the determination of step S2. Input (step S5), pointer 191
(Step S6), and the end of the data is determined (step S7). In this case, since there is still data, the process returns to step S2. Then, step S2, step S5, step S6 and step S7 are looped,
After "da", "shi", and "," are similarly added to the buffer 17, the next data is the word code [word 00808] according to the determination in step S2, and the flow advances to step S4.

The dictionary 15 is searched from the word number of the word code, and a corresponding character string, in this case, "stone crush" is extracted (step S4), and this character string is stored in a buffer 17 in step S5.
Add to Thereafter, a normal character string is added in the same loop, and the sentence code [000] is finally added as in the case of the first sentence.
[25] is restored and added to the buffer 17.

In step S7, the end of the data is determined.
The result restored in step S8 is displayed, and the process ends.

As described above, sentences, sections,
The original character string is restored from sentence data obtained by coding and compressing a character string identical or similar to a long character string such as a phrase.

[0043]

According to the sentence compression apparatus of the present invention, there are provided registration means for registering a specific character string among similar character strings from a sentence including a plurality of identical or similar character strings formed from a plurality of words; The identification data of the specific character string registered in the registration means and the similar character string in the sentence which is connected to the registration means, and the starting position and deletion of the character string to be deleted from the specific character string
Character string to be inserted instead of the number of characters to be deleted and the character string to be deleted
You and a conversion means for replacing the differential data, including the door
The start position is equal to or less than the first predetermined number from the start of the specific character string.
The specified character string is divided so that
2 so that the difference data is adjusted to be within a predetermined number.
A character string that is similar to the
Since the data is efficiently converted into the difference data, the compression rate of a sentence in which similar phrases appear frequently can be improved. In addition, register
Adjust the number of characters in a specific string and the string to be deleted.
Storage device using compressed data form
Can be stored efficiently as a form suitable for

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a text compression apparatus according to the present invention.

FIG. 2 is an explanatory diagram showing a part of an original sentence for explaining an example of compression by the sentence compression device in FIG. 1;

FIG. 3 is an explanatory diagram showing an example of a configuration of a dictionary for registering long character strings in the text compression apparatus of FIG. 1;

FIG. 4 is an explanatory diagram showing an example sentence in which a long character string is coded by the sentence compression apparatus of FIG. 1;

5 is a schematic diagram showing an example of a structure in which both the long character string and the word-based character string of the text compression apparatus of FIG. 1 are coded.

FIG. 6 is an explanatory diagram showing the structure of code data in the text compression apparatus of FIG. 1;

FIG. 7 is a flowchart of a main routine for explaining the operation of the text compression apparatus of FIG. 1;

8 is a subroutine flowchart for explaining the operation of the text compression apparatus of FIG. 1. FIG.

FIG. 9 is an explanatory diagram showing the structure of a dictionary for registering character strings in word units in a conventional text compression apparatus.

[Explanation of symbols]

 11 Control unit 12 Input unit 13 Display unit 14 String dictionary 15 Word dictionary 16 Compressed sentence database 17 Restoration sentence buffer 18 String dictionary buffer 19 Memory set 141 String dictionary index 142 String dictionary body 191 to 194 memory Pointer

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-206533 (JP, A) JP-A-2-297280 (JP, A) JP-A 64-66755 (JP, A) (58) Survey Field (Int.Cl. ⁶ , DB name) G06F 17/21-17/26 G06F 12/00

Claims (1)

(57) [Claims] 1. A registration unit for registering a specific character string among similar character strings from a sentence including a plurality of identical or similar character strings formed from a plurality of words, and a registration unit connected to the registration unit. The identification data of the specific character string registered in the registration unit with the similar character string in the sentence and the head position of the character string to be deleted from the specific character string;
The number of characters to be deleted and the sentence to be inserted in place of the character string to be deleted
And a converting means for replacing the difference data including the string, the head position is first from the head of the specific character string
Divide the specific character string so that it is within a predetermined number of 1
The number of characters to be deleted is adjusted to be within a second predetermined number.
A sentence compression apparatus characterized in that the sentence compression apparatus is configured to adjust the text.