CN101354727A - A method and device for establishing a link between a digital document catalog and a text - Google Patents

Abstract

The invention discloses a method and device for establishing a link between a digital document catalog and a text, which is used to provide a method for automatically establishing a link between a digital document catalog and a text, and improve the efficiency of establishing a link between a digital document and a text. The method includes obtaining at least one directory entry information from saving each directory entry information, determining each logical page corresponding to each directory entry in the digital document according to the at least one directory entry information; establishing each directory entry and corresponding Links between each logical page of the . According to the solution proposed by the present invention, by automatically establishing the link between the table of contents and the text of the digital document, the efficiency of establishing the link between the table of contents and the text of the digital document can be effectively improved, thereby increasing the production speed of the digital document.

Description

A method and device for establishing a link between a digital document catalog and a text

technical field

The invention relates to the technical field of document processing, in particular to a method and device for establishing a link between a digital document catalog and a text.

Background technique

The directory of the document can be used to index the document, which is convenient for readers to retrieve and read. For digital documents, general readers expect to be able to jump to the text part corresponding to the catalog item by clicking on a certain catalog item, so as to improve the speed of searching content and reading speed of readers.

In paper documents, there will be non-text parts such as copyright pages, catalog pages, prefaces, prefaces, postscripts, appendices, and reference documents in the front of the document or in the middle of the chapter. In the process of marking specific pages, generally Each content has its own page number sorting. For example, if there are 5 pages in the catalog page, the page number sorting method is from the first page to the fifth page, and the text part starts from the sixth page, but it is sorted according to the text part This page is the first page of the body part, and the page number corresponding to the body part recorded in the table of contents is also the first page, but this page number does not represent its real logical page number.

After paper documents are transformed into digital documents through Optical Character Recognition (OCR), or directly generated by document processing software, such as Adobe Acrobat or Founder Feiteng typesetting software, etc., digital documents record every The logical page of the page, that is, the digital document as a whole, and the position of each page in the whole. Therefore, there is no corresponding relationship between the natural page of the content marked by each directory entry recorded in the directory of the digital document and the logical page of the digital document. In the prior art, the link between the catalog page and the text of the digital document is generally completed manually, which has low efficiency, slow link establishment speed, and low accuracy.

Contents of the invention

In view of this, an embodiment of the present invention provides a method and device for establishing a link between a digital document catalog and a text, to automatically establish a link between a digital document catalog and a text, and improve the efficiency of establishing a link between a digital document catalog and a text .

An embodiment of the present invention provides a method for establishing a link between a digital document catalog and a text, wherein the digital document catalog contains a plurality of catalog entries, and each catalog entry contains at least one catalog item information, including:

Obtain at least one directory entry information from each saved directory entry, and determine each logical page corresponding to each directory entry in the digital document according to the at least one directory entry information;

Links are established between each directory entry and each corresponding logical page.

An apparatus for establishing a link between a digital document catalog and a text provided by an embodiment of the present invention, wherein the digital document catalog contains a plurality of catalog entries, and each catalog entry contains at least one catalog item information, including:

A logical page identification module, configured to obtain at least one directory entry information from each stored directory entry, and determine each logical page corresponding to each directory entry in the digital document according to the at least one directory entry information;

A link establishing module, configured to establish a link between each directory entry and each corresponding logical page.

A method for establishing a link between a digital document catalog and a text provided by an embodiment of the present invention can obtain at least one catalog item information according to the saved catalog entry information, and match the at least one catalog item information on the page of the digital document, Each logical page corresponding to each directory entry is determined according to the matching result, so as to establish a link between each directory entry and the logical page. By adopting the method for automatically establishing the link between the table of contents and the text of the digital document, the efficiency of establishing the link between the table of contents and the text of the digital document can be effectively improved, thereby improving the production efficiency of the digital document.

Description of drawings

Fig. 1 is a flow chart of a method for automatically establishing a link between a digital document catalog and a text provided by an embodiment of the present invention;

Fig. 2 is a specific implementation flowchart of a method for establishing a link between a digital document catalog and a text provided by an embodiment of the present invention;

3 is a flowchart of a method for determining each logical page corresponding to each directory entry according to the page number directory entry in the directory entry provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of determining character coordinates provided by an embodiment of the present invention;

5 is a flowchart of a method for determining each logical page corresponding to each directory entry according to the title directory entry in the directory entry provided by an embodiment of the present invention;

FIG. 6A is a specific implementation flowchart of a method for establishing a link between a digital document catalog and a text provided by an embodiment of the present invention;

FIG. 6B is a flow chart of a method for determining a logical page according to the page number bibliography information and the title bibliography information according to an embodiment of the present invention;

Fig. 7 is the catalog page of the digital document provided by the embodiment of the present invention;

Fig. 8 is the text page of the digital document provided by the embodiment of the present invention;

FIG. 9 is a structural diagram of an apparatus for establishing a link between a digital document catalog and a text provided by an embodiment of the present invention.

Detailed ways

In the embodiment of the present invention, in order to realize the automatic establishment of the link between the digital document catalog and the text, and improve the efficiency of link establishment between the digital document catalog and the text, as shown in Figure 1, a method for establishing a link between the digital document catalog and the text is provided. A method for interlinking, wherein the digital document directory includes multiple directory entries, and each directory entry contains at least one directory item information, which specifically includes the following steps:

S101: Obtain at least one directory entry information from each stored directory entry, and determine each logical page corresponding to each directory entry in the digital document according to the at least one directory entry information.

Wherein, the at least one piece of bibliographic item information obtained includes: page number bibliographic item information and/or title bibliographic item information.

S102: Establish a link between each directory entry and each corresponding logical page.

Embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

The data file used in the embodiment of the present invention can read the digital file page by page, and can obtain the characters of each page of the digital file, and can obtain the coordinate information of each character on each page, and can recognize the text Font information, that is, the font type, font size and other information of the text.

As shown in Figure 2, the method for establishing a link between the digital document catalog and the text in the embodiment of the present invention specifically includes the following steps:

S201: Read in the digital file, and obtain information about each stored directory entry.

The saved catalog entry is, according to the catalog information of the identified digital document, each line in the catalog is regarded as a catalog entry, and the catalog entry includes: chapter serial number catalog item, which is the chapter serial number information represented by the catalog row, for example, Chapter 2, Section 10, etc.; or the title table of contents item, which is the title information represented by the table of contents line, that is, the text information after the chapter number and before the page number information; or the page number table of contents item, which is the natural text information of the chapter in the table of contents line Page.

S202: Determine each logical page corresponding to each directory entry according to at least one directory entry information in each directory entry.

The at least one item of catalog item information in each catalog entry includes: the catalog item information of the page number in the catalog entry or the catalog item information according to the title in the catalog entry, or a combination of both.

S203: Establish a link between each directory entry and each corresponding logical page.

As shown in Figure 3, the method for determining each logical page corresponding to each directory entry according to the page number directory entry information in the directory entry provided by the embodiment of the present invention specifically includes the following steps:

S301: According to the page number information in the page number directory entry in each directory entry, determine the candidate page where the logical page corresponding to the page number is located.

According to the relationship between the preset logical page candidate page and the page number, determine the candidate page where the logical page of the page number is located, wherein the preset specification determines the page number corresponding to each catalog entry according to the page number information of each catalog entry The candidate page where the logical page is located includes: according to the page number in the page number catalog item, the total number of pages of the digital document catalog page and the set range threshold parameter, determine the candidate page where the logical page corresponding to the page number of the catalog entry is located, that is, determine the The candidate page where the logical page corresponding to the directory entry resides.

Specifically, when the page number in the page number catalog entry is n, the total number of pages in the digital document catalog page is K, and the range threshold parameter is set at the same time as D, then it can be known that the candidate page N where the logical page corresponding to the page number n is located is: n +K-D≤N≤n+K+D. In the actual calculation process, the size of the range threshold parameter D can be flexibly set according to needs. Using an appropriate range threshold parameter can improve the efficiency of link establishment and also meet the accuracy requirements.

S302: Extract effective information from each candidate page.

Specifically include: according to the saved information of the center range and the coordinates of each character in each candidate page, determine the characters outside the center range, and extract digital characters from the characters outside the center range. That is to determine the characters in the header and footer outside the center range, and extract the numeric characters from the characters. Among them, the saved information of the core range includes: the upper boundary line, the lower boundary line, the left boundary line and the right boundary line information of the core range,

The coordinates of each character include the coordinates of the character determined according to the minimum circumscribing rectangle of the character, and the coordinates of the character are represented by the coordinates of the two diagonal vertices of its minimum circumscribing rectangle, as shown in Figure 4, the character "order" The coordinates of vertex 1 and 3 can be represented by the coordinates of vertices 1 and 3, or the coordinates of vertices 2 and 4 can be used. For example, the coordinates of vertices 1 and 3 can be used to represent the coordinates of the character, and the coordinates of the character can be expressed as (x ₁ , y ₁ , x ₂ , y ₂ ), x ₁ is the abscissa of vertex 1, that is, the distance from vertex 1 to coordinate axis y, y ₁ is the ordinate of vertex 1, that is, the distance from vertex 1 to coordinate axis x, and x ₂ is the abscissa of vertex 3 Coordinates, that is, the distance from vertex 3 to the coordinate axis y, and y ₂ is the vertical coordinate of vertex 3, that is, the distance from vertex 3 to the coordinate axis x.

S303: Merge the extracted effective information.

According to the extracted digital character information, it is judged whether the distance between each two digital characters exceeds the set distance threshold, and when the distance between the two digital characters does not exceed the set distance threshold, the two digital characters are combined into one number String; otherwise, the two numeric characters are considered to be two separate numeric strings.

Wherein, when judging whether the distance between every two digital characters exceeds the set distance threshold, it can be judged according to the coordinates of every two digital characters. As shown in Figure 4, the method for determining the coordinates of each character is first to judge whether the two characters are It can be considered to be in the same line, wherein the specific judgment process can compare the vertical coordinates of the two characters, and when the absolute value of the difference between the vertical coordinates corresponding to the two numeric characters is less than the set first condition value, it is judged that the two Numerical characters are in the same line, otherwise they are in different lines, and the corresponding ordinate, that is, when the ordinate of vertex 3 of a numerical character is used, the ordinate of vertex 3 of the second digital character should also be used; then judge the two in the same line Whether the horizontal spacing of two numeric characters satisfies the set second condition value, such as comparing the abscissa values of two numeric characters, when the absolute value of the difference between the two abscissas corresponding to the abscissa is less than the set second condition value , it is determined that the two characters can be combined into a numeric character string. Of course, in the specific calculation process, it is also possible to determine whether two numeric characters are merged into a numeric character string according to other methods using coordinates, and details will not be repeated here.

S304: Match the page number information of the page number directory entry in the directory entry with the merged effective information, and determine the corresponding logical page in the directory entry according to the matching result.

Specifically include: comparing the size of the page number of the page number in the catalog entry with each merged character string, and determining whether each candidate page corresponds to the first page number of the catalog entry according to whether each merged character string is the same as the page number Directory entry confidence. The candidate page with the highest confidence of the first directory entry may be selected as the corresponding logical page in the directory entry.

The specific implementation process may include: first, for each candidate page in the candidate page where the logical page corresponding to the page number in the catalog entry page number is set, an identical initial confidence X is set, and the page number in the catalog entry page number is set to Match each combined number string in each candidate page. When a number string matching the page number in the directory entry is found, add Y to the confidence level corresponding to the candidate page. When the page number in the directory entry does not match the numeric string, E is subtracted from the confidence degree corresponding to the candidate page, so as to determine the first confidence degree of the candidate page corresponding to the directory entry. For example, the candidate page is combined to obtain a total of 5 numeric strings, the initial execution degree of the candidate page is X, one numeric string matches the page number in the catalog entry, and 4 numeric strings do not match the page number in the catalog entry , it can be seen that the confidence level corresponding to the candidate page is X+Y-4E. Among them, X, Y and E are all positive real numbers greater than zero.

At the same time, in the embodiment of the present invention, the logical page corresponding to each directory entry can also be determined according to the title directory entry in the directory entry. As shown in FIG. , a method for determining each logical page corresponding to each directory entry, specifically including the following steps:

S501: Arrange all the characters in each page into several rows according to the coordinates of all the characters in each page.

Specifically include: in each candidate page, sort all the characters, first judge whether every two characters are in the same line, take the typesetting direction of the digital document directory item as horizontal as an example, you can judge the vertical direction of the two characters according to Whether the spacing between the two characters does not exceed the preset spacing parameter h, where h is a positive real number. When the spacing between two characters in the vertical direction is not greater than the spacing parameter h, the two characters are arranged in a row; otherwise, the two characters are not The characters are arranged in one line; then in each line, the characters in each line are sorted according to the principle that the abscissa increases successively. As shown in Figure 4, after sorting, the minimum bounding rectangle of this line is (x _m , y _m , x _n , y _n ), and the minimum bounding rectangle of all characters in this line includes the minimum bounding rectangle of this line In the frame, x _m is the abscissa value of the leftmost character 1 in the line, the abscissa can be the abscissa of the upper left vertex or the abscissa of the lower left vertex of the character, and y _m is the abscissa value of the uppermost character 3 in the line The ordinate value, the ordinate can be the ordinate of the upper left vertex or the ordinate of the upper right vertex of the character, x _n is the abscissa value of the rightmost character 4 in the row, and the abscissa can be the ordinate of the upper right vertex of the character The abscissa or the abscissa of the lower right vertex, y _n is the ordinate value of the bottommost character 2 in the row, and the ordinate can be the ordinate of the lower left vertex or the ordinate of the lower right vertex of the character.

S502: In each line, match the characters in the line with the title information in the title directory entry in the saved directory entry.

The specific matching process includes: according to the Longest Common Subsequence (LCS) algorithm, perform similarity matching between strings, the string includes: the title in the directory entry and the characters of each line; at the same time, according to the settings At least one feature information of the row is used to determine the total confidence level of the row corresponding to the title directory item information.

Wherein, at least one feature information of the setting includes: the position of the characters in the line in the digital document page where they are located, or the size of the average character width of the characters in the line and the average character width of the body part, or the characters matched according to the LCS algorithm Whether the string is peered with other literal characters. According to the above at least one feature information and the LCS algorithm, the total confidence level of each line of characters corresponding to the title directory item information can be determined.

S503: Determine the corresponding logical page in the directory entry according to the matching result between each line in each page and the title information.

According to the matching degree of each row of characters and the title information, the total confidence is obtained, and the highest total confidence corresponding to each row in each page is used as the second directory entry confidence of the page corresponding to the directory entry. The second directory entry confidence level determines the logical page corresponding to each directory entry.

Of course, the logical page corresponding to each catalog entry is determined through the title information in the catalog entry. The specific implementation process is highly reliable, but it will also affect the efficiency of link establishment between the catalog and the text, so page number information and titles can be used Combining information to determine the logical page corresponding to each directory entry, specifically including: determining the candidate page where the logical page corresponding to the page number is located according to the page number information, matching the page number information in each candidate page, and determining that each candidate page corresponds to the directory Confidence of the first directory entry of the entry, and at the same time, match according to the title information in each candidate page to determine the second directory entry confidence of each candidate page corresponding to the directory entry, and according to the second directory entry confidence of each candidate page corresponding to the directory entry Confidence degree of a directory entry, and the confidence degree of the second directory entry for each candidate page corresponding to the directory entry, and setting the weight coefficient corresponding to the page number information matching and the title information matching, and determining the total confidence degree of each candidate page corresponding to the directory entry , to determine the logical page for each directory entry.

As shown in Figure 6A, in the embodiment of the present invention, "Mental Health Education" published by Inner Mongolia University Press in 2006 is taken as an example to specifically illustrate the method of establishing a link between the digital document catalog and the text, which specifically includes the following steps:

Step 601: Read in the digital file to obtain saved directory entry information.

The digital file has 236 pages and 59 table of contents entries. The process of establishing a link between the directory entry and the text is described in detail by taking the directory entry corresponding to the first section of the second chapter shown in FIG. 7 as an example. In this catalog entry, the chapter catalog item is "Section 1", the title catalog item is "Self-Awareness Overview", and the page number catalog item is "20".

Step 602: Determine the logical page corresponding to each directory entry according to at least one directory entry information set by the stored directory entry information.

Step 603: According to the determined logical page corresponding to each directory entry, establish a link between each directory entry and each corresponding logical page.

As shown in Figure 6B, in the embodiment of the present invention, according to the page number information of the page number directory entry in the directory entry and the title information in the title directory entry, the method for determining the logical page corresponding to each directory entry is specifically determined for each directory entry The corresponding logical page process includes:

Step 602a: According to the page number information in the directory entry, determine the candidate page where the logical page corresponding to each directory entry is located.

Wherein the page number of the directory entry is 20, according to the relationship between the candidate page and the page number where the logical page is located n+K-D≤N≤n+K+D, wherein the total number of pages K of the digital document is 5, If the range threshold parameter D is 3, it is determined that the candidate pages where the logical page corresponding to the directory entry is located are pages 22 to 28.

Step 602b: Extract valid information from each candidate page.

The core range information of the digital document saved in the embodiment of the present invention is that the ordinate of the upper boundary line is 80.73, the abscissa of the left boundary line is 0, the abscissa of the right boundary line is 485, and the ordinate of the lower boundary line is 697.10. In each candidate page, according to the coordinates of each character, determine characters outside the core range, and extract numeric characters from the characters outside the core range. In the specific calculation process, as shown in Figure 4, the coordinates of each character are determined according to the coordinates of vertex 1 and vertex 3 of the smallest circumscribed rectangular frame of the character. When the ordinate of vertex 1 of the character is smaller than 80.73, or the vertex When the ordinate of 3 is larger than 697.10, or the abscissa of vertex 1 is smaller than 0, or the abscissa of vertex 3 is larger than 485, it is considered that the character is located outside the center range.

Numeric characters are extracted from characters located outside the center range. Combine the proposed numeric characters. For example, to extract the numeric characters "7" and "1", the coordinates of the numeric character "7" are (421.05, 699.83, 425.76, 706.94), and the coordinates of the numeric character "1" are (416.74, 699.83, 419.47, 706.94) . Sort the extracted numeric characters according to their coordinates. For example, the abscissa of the vertex 1 of the numeric character "1" is greater than the abscissa of the vertex 1 of the numeric character "7", the abscissa of the vertex 3 of the numeric character "1" is smaller than the abscissa of the vertex 3 of the numeric character "7", and the numeric character "1" " and "7" correspond to the same ordinate, it can be seen that the two numeric characters are on the same line, and the numeric character "1" is on the left of the numeric character "7".

At the same time, the difference between the abscissa of the vertex 1 of the numeric character "7" and the abscissa of the vertex 3 of the numeric character "1" is 1.58, and the set distance threshold is a value between 2.37 and 4.71, so it can be known that the two numeric characters can be combined into A digital string, the combined digital string is "17", and the coordinates of the digital string are (416.74, 699.83, 425.76, 706.94).

Step 602c: Match the extracted valid information with the page number information in the saved directory entry, and determine the first directory entry confidence level of each candidate page corresponding to the directory entry.

Compare the combined number string with the page number information in the table of contents entry. The page number information in this catalog entry is 20, and the numeric string after it is 17, and the two numeric characters do not match. Therefore, the confidence degree of the candidate page is subtracted by E, the initial confidence degree X of this embodiment is 50, and E is 6, so it can be known that the confidence degree of the candidate page is 44.

Using the above method, it can be obtained that the confidence levels of the first directory entry obtained after page number matching for each candidate page whose natural page number is from page 22 to page 28 are 44, 44, 44, 80, 44, 44, respectively. 44.

Step 602d: According to the coordinates of all the characters in each page, arrange all the characters in several rows on each page.

In order to ensure that all characters on each page are arranged in rows, the vertical distance between the horizontal central axes of the characters needs to meet certain conditions during the arrangement process. The vertical distance of the horizontal central axes between the characters can be calculated according to the upper end of the characters and Determine the average value of the vertical coordinates of the two vertices at the lower end, and then calculate the difference between the average values of the corresponding vertical coordinates of the two characters. In the embodiment of the present invention, the method for judging whether two characters A and B can be arranged in a row is: calculate the average value of the two ordinates of character A, and calculate the larger ordinate and the smaller ordinate of character A At the same time, calculate the average value of the two vertical coordinates of character B, and calculate the difference between the larger vertical coordinate and the smaller vertical coordinate of character B, and determine the average value of the corresponding vertical coordinates of characters A and B Whether the difference is smaller than the product of the difference between the smaller and larger ordinate and the smaller ordinate of the two characters A and B and the parameter, that is, to judge:

$<span\; class="notranslate">\; |</span>\frac{{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; MIN</span>}<span\; class="notranslate">\; [</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; j</span>}$

Among them, MIN means to take the smaller value of the two, j is a positive real number less than 1, Y ₁ (A) is the smaller ordinate value of character A, and Y ₂ (A) is the larger ordinate value of character A Y ₁ (B) is the smaller ordinate value of character B, and Y ₂ (B) is the larger ordinate value of character B. When the judgment result is yes, arrange A and B in one line, otherwise arrange A and B in different lines, and then judge whether the vertical coordinates of the two characters B and C meet the above conditions in turn, and judge whether B and C are arranged in one line . Use this method to arrange all the characters on each page. After being arranged by this method, each row corresponds to a minimum circumscribed rectangular frame, as shown in Figure 4.

Step 602e: match each row of each candidate page with the title information in the directory entry, and determine the second directory entry confidence level of each candidate page corresponding to the directory entry.

Step 602f: According to the first directory entry confidence degree corresponding to each directory entry of each candidate page and the second confidence degree corresponding to each directory entry, determine the total confidence degree of each candidate page corresponding to each directory entry, according to the total Confidence determines which logical page each directory entry corresponds to.

According to the first directory entry confidence degree dPageVeri of each candidate page corresponding to the directory entry, the second directory entry confidence degree +dTitleVeri of the corresponding directory entry, and the weight coefficient dPageWeight corresponding to the first directory entry confidence degree and the second directory entry confidence degree corresponding The weight coefficient dTitleWeight of each candidate page is determined to correspond to the total confidence of each directory entry, wherein the sum of the weight coefficient dPageWeight corresponding to the confidence degree of the first directory entry and the weight coefficient dTitleWeight corresponding to the confidence degree of the second directory entry is 1, and Both are positive real numbers greater than zero, for example, dPageWeight is 0.4, and dPageWeight is 0.6. Using the method for determining the total confidence above, the total confidence of the candidate page whose natural page is the 25th page as shown in FIG. 8 is 94. The candidate page with the highest total confidence is selected as the logical page corresponding to the directory entry. At the same time, a total confidence threshold may also be set, and candidate pages whose total confidence exceeds the total confidence threshold are used as logical pages corresponding to the directory entry.

Wherein, the process of determining the confidence degree of the second directory entry corresponding to each candidate page includes:

As shown in Figure 8, the arranged natural page provided by the embodiment of the present invention is the content of the 25th page, and the characters of each line in the candidate page are matched with the title characters in the directory entry by using the LCS algorithm, and determined according to the matching result Each row in the candidate page corresponds to the confidence level of the first directory item information of the title directory information, and the process of determining the confidence level of the second directory item information includes: determining the position of the characters in each row in the candidate page in each row, according to the position Determine the second confidence level of each line, and compare the average text width of each line of characters with the average text width of the body part, determine the third confidence level of each line, and at the same time determine the string according to the successful match of the LCS algorithm Whether it goes with other text characters, determine the fourth confidence degree corresponding to each line, and determine the corresponding The second directory entry information confidence degree of the title directory entry information is used to determine the total directory entry information confidence degree of each row according to the first directory entry information confidence degree and the second directory entry information confidence degree. According to the confidence degree of the total directory entry information of each line in each page, the value with the largest total confidence degree is taken as the second directory entry confidence degree of the candidate page corresponding to the directory entry.

The LCS algorithm is used to match the characters of each line in the candidate page with the title in the directory entry. The input parameters of the algorithm are two strings, which are the title of the directory entry and the string of the row to be matched. After calculation, the longest common substring part of the two character strings is returned. According to the returned longest common character string part, the similarity of the two character strings can be determined to determine the confidence level of the first directory item information of the row. For example, match the characters "Summary of Self-Awareness Section 1" on the second line of page 25 with the title of the catalog entry "Summary of Self-Awareness" according to the LCS algorithm. If the result is the same as the title of the directory entry, it can be determined that the confidence level of the first directory entry information in this row is 100. A row with a higher confidence degree of the first directory entry information has a higher similarity between the characters of the row and the title of the directory entry.

And judge the character position of each line. The process of judging the character position of each line specifically includes: comparing the absolute value of the horizontal distance difference between the first central axis determined according to the coordinates of the row where the characters of each line are located, and the second central axis determined according to the left and right boundary lines of the center range , and determine the second confidence level of each row according to the absolute value of the horizontal distance difference. The row with the higher second confidence level has a smaller absolute value of the horizontal distance difference.

And when determining the position of the characters of each line, it can also be determined according to the coordinates of each line whether the approximate position of the characters of each line is located in the middle position determined according to the left and right boundary lines of the center range, when the characters of this line are located in the middle position, determine whether the length of the line satisfies the set length condition according to the coordinates of the line. Whether the set length condition is satisfied, determine the second confidence level of the line; or when the character of the line is located on the left side of the core, determine whether the length of the line meets the set length condition according to the coordinates of the line, For example, if the set length condition is less than 70% of the difference between the right boundary line and the left boundary line of the entire core range, the second confidence level of the line is determined.

Wherein, when determining the approximate position of the characters of each line according to the coordinates of each line, such as the line coordinates shown in Figure 4, the first difference between X _m and the left boundary line of the version center range in the coordinates of each line can be compared, and The size of the second difference between the right boundary line of the core range and X _n , when the difference between the first difference and the second difference is greater than the set difference threshold, it is judged that the characters in this line are located on both sides of the entire core , and when the first difference is larger than the second difference, it is judged that the characters in this row are located at the right end of the entire version center, and when the first difference is smaller than the second difference, it is judged that the characters in this row are located at the left end of the entire version center . Of course, there may be many methods in the actual position judgment process, but the method of judging the position of each line of characters based on the coordinate difference based on the idea of the embodiment of the present invention should be within the protection scope of the present invention.

Simultaneously judge the size of the average text width of each line of characters and the average text width of the text of the digital document, for example, the average text width of the second line in Figure 8 is 13.77, the average text width of the text in this digital document is 10.29, the second line The average text width of is greater than the average text width of the body text in the digital document, determine the third confidence level corresponding to the row. Among them, the row with the higher third confidence degree has a larger average text width of the characters in the row.

And judge whether there are other literal characters in the row according to the strings that are successfully matched by the LCS algorithm. In the process of specifically judging whether there are other characters in the line, the text characters directly adjacent to the coordinates of the successfully matched character string are determined as other text characters in the line. When there are text characters that match the When there is an indirect connection relationship between successful characters, such as "Second Section Self-Awareness Overview", the successfully matched character is "Self-Awareness Overview", and the coordinates connected with this string are spaces, and "Second Section" and this character There is an indirect connection relationship between strings, it can be considered that there are no other literal characters in the row where the successfully matched string is located, and the fourth confidence level of the row is determined according to whether there are other literal characters in the row where the successfully matched string is located Spend.

According to the confidence degree of the first directory entry information of each row, the second directory entry information confidence degree determined by the second confidence degree, the third confidence degree and the fourth confidence degree, and the weight coefficient corresponding to each confidence degree, determine each The confidence degree of the total directory entry information of the row, the value with the highest confidence degree of the total directory entry information is taken as the second directory entry confidence degree of each candidate page corresponding to the directory entry, wherein the weight coefficient corresponding to each confidence degree is a positive real number.

A method for establishing a link between a digital document catalog and a text provided by an embodiment of the present invention can obtain at least one catalog item information according to the saved catalog entry information, and match the at least one catalog item information on the page of the digital document, Each logical page corresponding to each directory entry is determined according to the matching result, so as to establish a link between each directory entry and the logical page. By adopting the method for automatically establishing the link between the table of contents and the text of the digital document, the efficiency of establishing the link between the table of contents and the text of the digital document can be effectively improved, thereby improving the production efficiency of the digital document.

At the same time, because in digital documents, the main factors that affect the mismatch between the natural pages in the catalog entry and the actual logical pages are the copyright page, catalog page, preface, preface and appendix before the main text, so as long as the catalog of the digital document is established and In the process of linking between texts, the number of pages of content such as the copyright page, catalog page, preface, preface and appendix before the text is identified, and according to the number of pages and the page number information in the catalog entry of the saved digital document, it is also possible to determine each Each directory entry corresponds to a logical page, thereby establishing a link between each directory entry and each logical page. In the specific implementation process, it is believed that those skilled in the art can implement the specific implementation according to the method provided by the embodiment of the present invention, so details will not be repeated here.

As shown in Figure 9, an embodiment of the present invention provides an apparatus for establishing a link between a digital document catalog and a text, wherein the digital document catalog contains a plurality of catalog entries, and each catalog entry contains at least one catalog item information, include:

A logical page identification module 90, configured to obtain at least one directory entry information from each stored directory entry, and determine each logical page corresponding to each directory entry in the digital document according to the at least one directory entry information;

A link establishing module 91, configured to establish a link between each directory entry and each corresponding logical page.

The logical page identification module 90 includes:

The first identification unit 901 is configured to determine each logical page corresponding to each directory entry in the digital document when the obtained at least one directory entry information is page number directory entry information.

The first identification unit 901 includes:

The first candidate page determination subunit 9010 is configured to determine the candidate page where the logical page corresponding to each directory entry is located according to the page number directory entry information of each directory entry according to preset rules;

The first matching subunit 9011 is used to extract valid information from each candidate page, and compare whether each valid information is the same as the page number directory entry information in the directory entry;

The first calculation subunit 9012 is configured to determine the first confidence level of each candidate page corresponding to the directory entry according to whether each valid information is the same as the directory entry information of the page number;

The logical page first determining subunit 9013 is configured to determine each logical page corresponding to each directory entry according to the first confidence level.

The logical page identification module 90 includes:

The second identifying unit 902 is configured to determine each logical page corresponding to each directory entry in the digital document when at least one piece of directory entry information acquired is title directory entry information.

The second identification unit 902 includes:

The first line confidence determination subunit 9020 is used to determine that each line of characters in the page of digital documents corresponds to the title directory item according to the similarity between the title directory item information in each directory entry and the characters in each line of digital documents on each page the first degree of confidence of the information;

The second line confidence determination subunit 9021 is configured to determine the second confidence level of each line of characters in the page of digital documents corresponding to the title directory entry information according to at least one feature information of each line of characters in the page of digital documents;

The second calculation subunit 9022 is configured to determine the second confidence level of the page of digital documents corresponding to the directory entry according to the total confidence level of each line of characters in the page of digital documents corresponding to the title directory entry information;

The logical page second determining subunit 9023 is configured to determine each logical page corresponding to each directory entry information according to the second confidence level.

Wherein at least one characteristic information in the second determining subunit 9021 of the line confidence includes: the position information of each line of characters in the digital document, or the average text width information of each line of characters in the digital document, or the content of the digital document and the title directory item Information whether identical characters are peered with other literal characters.

The logical page identification module 90 includes:

The third identifying unit 903 is configured to determine each logical page corresponding to each directory entry in the digital document when the at least one directory entry information is page number directory entry information and title directory entry information.

The third identification unit 903 includes:

The second candidate page determining subunit 9030 is configured to determine the candidate page where the logical page corresponding to each directory entry is located according to the page number directory entry information in each directory entry;

The first confidence level determination subunit 9031 is configured to determine the first confidence level in each directory entry corresponding to each candidate page;

The second confidence level determination subunit 9032 is configured to determine the second confidence level in each directory entry corresponding to each candidate page;

A total confidence determination subunit 9033, configured to determine the total confidence of each candidate page corresponding to each directory entry according to the first confidence and the second confidence;

The third logical page determination subunit 9034 is configured to determine the logical page corresponding to each directory entry according to the total confidence.

The first confidence determination subunit 9031 includes:

The first matching submodule is used to extract valid information from each candidate page, and compare whether each valid information is the same as the page number directory item information in the directory entry;

The first calculation sub-module is configured to determine the first directory entry confidence level of each candidate page corresponding to the directory entry according to whether each valid information is the same as the page number directory entry information.

The second confidence determination subunit 9032 includes:

The first determination submodule of line confidence is used to determine the character of each line of the candidate page corresponding to the title directory item information according to the similarity between the title directory item information in each directory entry and each line of characters in each candidate page Confidence degree of the information of the first entry;

The second determination submodule of line confidence is used to determine the second directory item information confidence level of each line of characters in the candidate page corresponding to the title directory item information according to at least one characteristic information of each line of characters in the candidate page;

The second calculation submodule is used to determine the second directory entry confidence level of the candidate page corresponding to the directory entry according to the total confidence level of each row of characters in the candidate page corresponding to the directory entry information of the title.

A method for establishing a link between a digital document catalog and a text provided by an embodiment of the present invention can obtain at least one catalog item information according to the saved catalog entry information, and match the at least one catalog item information on the page of the digital document, Each logical page corresponding to each directory entry is determined according to the matching result, so as to establish a link between each directory entry and the logical page. By adopting the method for automatically establishing the link between the table of contents and the text of the digital document, the efficiency of establishing the link between the table of contents and the text of the digital document can be effectively improved, thereby improving the production efficiency of the digital document.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (15)

1. A method for establishing a link between a digital document catalog and a text, wherein the digital document catalog includes a plurality of catalog entries, and each catalog entry contains at least one catalog item information, characterized in that it includes: Obtain at least one directory entry information from each saved directory entry, and determine each logical page corresponding to each directory entry in the digital document according to the at least one directory entry information; Links are established between each directory entry and each corresponding logical page. 2. The method according to claim 1, wherein said obtaining at least one directory item information comprises: Obtain page number table of contents information and/or title table of contents information. 3. The method according to claim 2, wherein when the obtained at least one catalog item information is page number catalog item information, determining each logical page corresponding to each catalog entry in the digital document comprises: Determine the candidate page where the logical page corresponding to each directory entry is located according to the page number directory entry information of each directory entry according to preset rules; Extract valid information from each candidate page, and compare whether each valid information is the same as the page number catalog item information in the catalog entry; According to the comparison result of each valid information and the page number directory entry information, determine the first directory entry confidence level of each candidate page corresponding to the directory entry; Each logical page corresponding to each directory entry is determined according to the first directory entry confidence. 4. The method according to claim 2, wherein when at least one catalog item information acquired is title catalog item information, determining each logical page corresponding to each catalog entry in the digital document comprises: According to the similarity between the title directory entry information in each directory entry and each line of characters in each page of digital documents, determine the first directory entry information confidence level of each line of characters in this page of digital documents corresponding to the title directory entry information; According to at least one feature information of each line of characters in the digital document on the page, determine the confidence level of the second directory entry information corresponding to the title directory entry information for each line of characters in the digital document on the page; According to the first directory entry information confidence degree and the second directory entry information confidence degree of each line of characters in the digital document corresponding to the title directory information, determine the total content of each line of characters in the page digital document corresponding to the title directory entry information item information confidence; Determine the second directory entry confidence level of the page digital file corresponding to the directory entry according to the confidence level of the total directory entry information that each row of characters in the digital document corresponds to the title directory entry information; Each logical page corresponding to each directory entry information is determined according to the second directory entry confidence. 5. The method according to claim 4, wherein the at least one feature information includes: The position information of each line of characters in the digital document, or the average text width information of each line of characters in the digital document, or information on whether the characters in the digital document that are completely similar to the title directory item information go with other text characters. 6. The method according to claim 2, wherein when the at least one catalog item information is page number catalog item information and title catalog item information, each logical page corresponding to each catalog entry is determined in the digital document include: According to the page number directory entry information in each directory entry, determine the candidate page where the logical page corresponding to each directory entry is located; Extract valid information from each candidate page, compare whether each valid information is the same as the page number directory item information in the directory entry, and determine whether each candidate page corresponds to the a first directory entry confidence for the directory entry; and According to the similarity between the title directory item information in each directory entry and each line of characters in each candidate page, determine the confidence level of the first directory item information corresponding to the title directory item information for each line of characters in the candidate page; At least one feature information of each line of characters in the page, determine the confidence level of the second directory item information corresponding to the title directory item information for each line of characters in the candidate page; according to the first directory item corresponding to each line of characters in the candidate page Information confidence degree and the second directory entry information confidence degree, determine the total directory entry information confidence degree of each row of characters in the candidate page corresponding to the title directory entry information; The confidence level of the total directory item information determines the confidence level of the second directory entry corresponding to the directory entry in the digital document on this page; determining the total confidence of each candidate page corresponding to each directory entry according to the first directory entry confidence and the second directory entry confidence; A logical page corresponding to each directory entry is determined according to the total confidence. 7. A device for establishing a link between a digital document catalog and a text, wherein the digital document catalog contains a plurality of catalog entries, and each catalog entry contains at least one catalog item information, wherein the device includes: A logical page identification module, configured to obtain at least one directory entry information from each stored directory entry, and determine each logical page corresponding to each directory entry in the digital document according to the at least one directory entry information; A link establishing module, configured to establish a link between each directory entry and each corresponding logical page. 8. The device according to claim 7, wherein the logical page identification module comprises: The first identifying unit is configured to determine each logical page corresponding to each directory entry in the digital document when the obtained at least one directory entry information is page number directory entry information. 9. The device according to claim 8, wherein the first identification unit comprises: The first candidate page determination subunit is configured to determine the candidate page where the logical page corresponding to each directory entry is located according to the page number directory entry information of each directory entry according to preset rules; The first matching subunit is used to extract valid information from each candidate page, and compare whether each valid information is the same as the page number directory entry information in the directory entry; The first calculation subunit is used to determine the first catalog entry confidence level of each candidate page corresponding to the catalog entry according to whether each valid information is the same as the catalog entry information of the page number; The logical page first determining subunit is configured to determine each logical page corresponding to each directory entry according to the first directory entry confidence. 10. The device according to claim 7, wherein the logical page identification module comprises: The second identifying unit is configured to determine each logical page corresponding to each directory entry in the digital document when the acquired at least one directory entry information is title directory entry information. 11. The device according to claim 10, wherein the second identification unit comprises: The first determining subunit of line confidence is used to determine the corresponding title directory item information for each line of characters in the digital document on the page according to the similarity between the title directory item information in each directory entry and the characters in each line of digital documents on each page The confidence level of the first entry information; The second determination subunit of line confidence is used to determine the second directory item information confidence level of each line of characters in the page of digital documents corresponding to the title directory item information according to at least one characteristic information of each line of characters in the page of digital documents; The second calculation subunit is used to determine the second directory entry confidence level of the page digital document corresponding to the directory entry according to the total confidence level of each line of characters in the page digital document corresponding to the title directory entry information; The second logical page determining subunit is configured to determine each logical page corresponding to each directory entry information according to the second confidence level. 12. The device according to claim 7, wherein the logical page identification module comprises: The third identifying unit is configured to determine each logical page corresponding to each directory entry in the digital document when the at least one directory entry information is page number directory entry information and title directory entry information. 13. The device according to claim 12, wherein the third identification unit comprises: The second candidate page determination unit is configured to determine the candidate page where the logical page corresponding to each directory entry is located according to the page number directory entry information in each directory entry; A first confidence determination subunit, configured to determine the confidence of each candidate page corresponding to the first directory entry in each directory entry; The second confidence determination subunit is configured to determine the confidence of each candidate page corresponding to the second directory entry in each directory entry; A total confidence determination subunit, configured to determine the total confidence of each candidate page corresponding to each directory entry according to the first directory entry confidence and the second directory entry confidence; The third logical page determination subunit is configured to determine the logical page corresponding to each directory entry according to the total confidence. 14. The device according to claim 13, wherein the first confidence determination subunit comprises: The first matching submodule is used to extract valid information from each candidate page, and compare whether each valid information is the same as the page number directory item information in the directory entry; The first calculation sub-module is configured to determine the first directory entry confidence level of each candidate page corresponding to the directory entry according to whether each valid information is the same as the page number directory entry information. 15. The device according to claim 13, wherein the second confidence determination subunit comprises: The first determination submodule of line confidence is used to determine the character of each line of the candidate page corresponding to the title directory item information according to the similarity between the title directory item information in each directory entry and each line of characters in each candidate page Confidence degree of the information of the first entry; The second determination submodule of line confidence is used to determine the second directory item information confidence level of each line of characters in the candidate page corresponding to the title directory item information according to at least one characteristic information of each line of characters in the candidate page; The second calculation submodule is used to determine the second directory entry confidence level of the candidate page corresponding to the directory entry according to the total confidence level of each row of characters in the candidate page corresponding to the directory entry information of the title.

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