PDF document conversion method and device, equipment, storage medium and product

Abstract

The invention relates to the technical field of computers, and discloses a PDF document conversion method and device, equipment, a storage medium and a product, and the method comprises the steps: obtaining a to-be-converted PDF document and page information of the PDF document; analyzing the PDF document page by page based on the page information to obtain webpage elements corresponding to content types of all pages in the PDF document; rendering is carried out based on the webpage elements, and a webpage corresponding to the PDF document is generated. By analyzing the PDF document page by page, the processing concurrency amount caused by full-text analysis can be avoided, meanwhile, the accuracy of an analysis result and the accuracy of a subsequent rendering result can be guaranteed, and on the basis, it is guaranteed that the webpage can truly represent the PDF document. Meanwhile, the webpage page with the structured mark is generated through the webpage element, so that the content with the logic relation in semantics can also present a complete logic structure on the page, and subsequent retrieval and comparison display of similar content on the basis can be facilitated.

Description

Technical Field

[0001] The present invention relates to the field of computer technology, and in particular to a PDF document conversion method, device, equipment, storage medium and product. Background Art

[0002] For files, they are generally described by PDF documents to avoid modification or format display problems. For the display of PDF documents, PDF documents need to be retrieved and compared in some scenarios. Therefore, it is necessary to provide a PDF document conversion method to facilitate display using the converted content. Summary of the invention

[0003] In view of this, the present invention provides a PDF document conversion method, device, equipment, storage medium and product to solve the PDF document conversion problem.

[0004] In a first aspect, the present invention provides a method for converting a PDF document, the method comprising:

[0005] Obtaining the PDF document to be converted and page information of the PDF document;

[0006] Parsing the PDF document page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document, wherein the content type includes at least one of text, vector graphics, images, and tables, and the web page elements are used to form a web page;

[0007] Rendering is performed based on the web page elements to generate a web page corresponding to the PDF document.

[0008] The PDF document conversion method provided by the embodiment of the present invention parses the PDF document page by page to obtain the web page elements corresponding to the content type of each page in the PDF document, that is, to obtain the corresponding web page elements for different content types, and render the web page elements obtained after parsing, thereby generating the web page corresponding to the PDF document. By parsing the PDF document page by page, the processing concurrency caused by the full-text parsing can be avoided. At the same time, the page-by-page parsing can also ensure the accuracy of the parsing results and the accuracy of the subsequent rendering results. On this basis, it is ensured that the web page can truly represent the PDF document. Representing the PDF document by the web page can facilitate the subsequent retrieval and comparative display of similar content on this basis.

[0009] In an optional implementation, if the content type includes text, the corresponding web page element includes a text element, and the PDF document is parsed page by page based on the page information to obtain the web page element corresponding to the content type of each page, including:

[0010] Determine the current page to be parsed based on the page information;

[0011] The text in the current page to be parsed is parsed to determine the hyphenation information and sentence segmentation information of the text to obtain the text element.

[0012] The PDF document conversion method provided by the embodiment of the present invention can determine the current page to be parsed through page information, and can accurately obtain the PDF page that needs to be processed currently. At the same time, by determining the quantum information and sentence segmentation information of the text during parsing, the display consistency of the text elements and the text in the PDF is further guaranteed.

[0013] In an optional implementation, parsing the text in the current page to be parsed, determining the hyphenation information and sentence segmentation information of the text, and obtaining the text element includes:

[0014] Determining feature information of each character in each line of text;

[0015] Characters in the same row and adjacent rows are hyphenated or segmented based on the feature information, the hyphenation information and the segmentation information are determined, and the text element is obtained.

[0016] The PDF document conversion method provided by the embodiment of the present invention utilizes the characteristic information of characters to perform character ligature or sentence segmentation processing on the same line and adjacent lines respectively, and ensures accurate display of characters by character ligature or sentence segmentation.

[0017] In an optional implementation, the step of hyphenating or segmenting text in the same line and adjacent lines based on the feature information, determining the hyphenation information and segmentation information, and obtaining the text element includes:

[0018] For characters in the same row, calculating the degree of association between two adjacent characters based on the feature information;

[0019] If the correlation degree is greater than a preset correlation value, the two adjacent characters are combined into a ligature information, otherwise, a sentence is segmented between the two adjacent characters to form a sentence segmentation information;

[0020] For characters in adjacent rows, calculating a first page margin of a first character in a first row of the adjacent rows and a second page margin of a last character in a second row of the adjacent rows based on the feature information, the second row being located above the first row;

[0021] If the difference between the first page margin and the second page margin is less than the preset margin value, the first character of the first line and the last character of the second line are used to form hyphenation information; otherwise, a sentence is broken between the first character of the first line and the last character of the second line to form sentence break information.

[0022] The PDF document conversion method provided by the embodiment of the present invention uses different methods to perform hyphenation or sentence segmentation processing on the same line and adjacent lines, respectively, and can further ensure the accuracy of the obtained hyphenation information and sentence segmentation information.

[0023] In an optional implementation, if the content type includes vector graphics, the web page element includes a vector graphics element, and the PDF document is parsed page by page based on the page information to obtain the web page element corresponding to the content type of each page in the PDF document, including:

[0024] Extracting line information of the vector graphic in a current page to be parsed, wherein the current page to be parsed is determined based on the page information;

[0025] Based on the line information, determining a fill area of ​​the vector graphic;

[0026] Color filling is performed in the filling area to obtain the vector graphic element.

[0027] The PDF document conversion method provided by the embodiment of the present invention, for vector graphics, obtains the corresponding filling area by extracting the line information of the vector graphics, and performs color filling on this basis, so as to obtain the vector graphic elements consistent with the vector graphics in the PDF.

[0028] In an optional implementation, if the content type includes an image, the web page element includes an image element; and the step of parsing the PDF document page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document includes:

[0029] Extracting an image from a current page to be parsed and determining an image format of the image, wherein the current page to be parsed is determined based on the page information;

[0030] The image is parsed according to the image format to obtain image elements.

[0031] The PDF document conversion method provided by the embodiment of the present invention determines the image format of the image in the PDF and then parses the image based on the image format to obtain the image element, thereby ensuring the consistency between the image element and the PDF document.

[0032] In an optional implementation, if the content type includes a table, the web page element includes a table element, and the PDF document is parsed page by page based on the page information to obtain the web page elements of each page, including:

[0033] Extracting line segments of the table in the current page to be parsed, and determining position information of each line segment in the current page to be parsed, wherein the current page to be parsed is determined based on the page information;

[0034] Based on the position information of each line segment, a table element of the current page to be parsed is generated.

[0035] In the PDF document conversion method provided by the embodiment of the present invention, for a table, since the text in the table is parsed using a text processing method and the line segments in the table do not need to be compared for similarity, it is necessary to accurately determine the position information of the line segments in the table, thereby ensuring the consistency between the table elements and the table in the PDF document.

[0036] In an optional implementation, the rendering based on the web page element to generate a web page corresponding to the PDF document includes:

[0037] Determining a rendering tag of the web page element based on feature information of the web page element, wherein the feature information of the web page element includes character style and sentence features, and the sentence features are determined based on hyphenation information and sentence segmentation information of the text;

[0038] Structuring the webpage elements based on the rendering tags to obtain structured information;

[0039] Rendering is performed according to the structured information to generate the web page.

[0040] The PDF document conversion method provided by the embodiment of the present invention determines the rendering tag based on the characteristic information of the web page element, thereby ensuring that the determined rendering tag can represent the characteristics of the web page element, so that the structured processing result can ensure consistency with the PDF document.

[0041] In an optional implementation, structuring the webpage element based on the rendering tag to obtain structured information includes:

[0042] Detecting whether there are similar elements to the web page elements;

[0043] When there are similar elements to the web page element, generating tag information of the web page element;

[0044] Based on the marking information and the rendering tag, the web page element is structured to obtain structured information.

[0045] The PDF document conversion method provided by the embodiment of the present invention also performs a similarity comparison on the web page elements during the process of generating a web page. If a similar element exists, the marking information of the web page element is generated, and the web page element is structured in combination with the rendering tag, thereby ensuring that the similarity comparison mark can be displayed in the web page.

[0046] In an optional implementation manner, the marking information includes a marking position and marking content; when there are similar elements among the web page elements, generating the marking information of the web page elements includes:

[0047] When there are similar elements to the webpage element, associating the first identification information corresponding to the webpage element with the second identification information corresponding to the similar element;

[0048] Based on the first identification information and the second identification information, determining a marking position and marking content of the web page element in the web page;

[0049] The first identification information is used to represent the uniqueness of the web page element, and the second identification information is used to represent the uniqueness of the similar comparison element.

[0050] The PDF document conversion method provided by the embodiment of the present invention can facilitate users to quickly locate similar content in the document by comparing and displaying web page elements and similar elements in a web page using first identification information and second identification information.

[0051] In a second aspect, the present invention provides a PDF document conversion device, the device comprising:

[0052] An acquisition module, used to acquire the PDF document to be converted and page information of the PDF document;

[0053] A parsing module, configured to parse the PDF document page by page based on the page information, and obtain web page elements corresponding to the content type of each page in the PDF document, wherein the content type includes at least one of text, vector graphics, images, and tables, and the web page elements are used to form a web page;

[0054] The rendering module is used to render based on the web page elements to generate a web page corresponding to the PDF document.

[0055] In a third aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the PDF document conversion method of the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0056] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the PDF document conversion method of the first aspect or any corresponding embodiment thereof.

[0057] In a fifth aspect, the present disclosure provides a computer program product, including computer instructions, which are used to enable a computer to execute the PDF document conversion method of the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0059] Figure 1 is a flowchart of a method for converting a PDF document according to an embodiment of the present invention;

[0060] Figure 2 is a flowchart of another PDF document conversion method according to an embodiment of the present invention;

[0061] Figure 3 is a flowchart of another PDF document conversion method according to an embodiment of the present invention;

[0062] Figure 4 is a schematic diagram of a web page according to an embodiment of the present invention;

[0063] Figure 5 is a structural block diagram of a PDF document conversion device according to an embodiment of the present invention;

[0064] Figure 6 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0066] In the related art, the PDF document is converted into text, or the entire PDF document is used as a picture for image recognition, or the PDF document is converted in a mixed manner.

[0067] However, in the method of converting PDF documents into text, the processing effect of complex typesetting in PDF documents (for example, multi-column text, mixed text and graphics) is poor, and it is difficult to process non-text content (for example, images, watermarks, lines, and filled graphics).

[0068] In the method of treating the entire PDF document as a picture for image recognition, the amount of calculation required to treat it as a complete image is huge, resulting in a slow processing speed and extremely high requirements for computing resources.

[0069] In the method of converting PDF documents in a hybrid manner, by extracting text and images separately, although it is possible to more comprehensively process various elements in the PDF document, the original style of the PDF document is lost, resulting in the conversion result being inconsistent with the format of the original PDF document.

[0070] Based on this, the PDF document conversion method provided by the embodiment of the present invention parses the PDF document page by page to obtain the web page elements corresponding to each page, and then renders them to obtain the web page. That is, by converting the PDF document into a web page for display, the accuracy of the parsing result and the accuracy of the subsequent rendering result are guaranteed by parsing page by page, and on this basis, it is guaranteed that the web page can truly represent the PDF document.

[0071] According to an embodiment of the present invention, an embodiment of a method for converting a PDF document is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0072] In this embodiment, a PDF document conversion method is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 1 is a flowchart of a method for converting a PDF document according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0073] Step S101, obtaining a PDF document to be converted and page information of the PDF document.

[0074] The PDF document to be converted is used to represent the PDF document that currently needs to be converted. The PDF document can be uploaded to the electronic device by the user through interaction with the electronic device; it can also be stored in the electronic device and obtained from the electronic device when conversion is required; or it can also be obtained after the electronic device interacts with a third-party device.

[0075] The page information of a PDF document is used to represent the number of pages of a PDF document, so as to facilitate subsequent statistics on which page of the PDF document is currently parsed. The page information can be obtained by analyzing the directory of the PDF document, or by obtaining the page number information of the PDF document, etc.

[0076] There is no limitation on the method of obtaining PDF documents and their page information, which can be set according to actual needs.

[0077] Step S102: parsing the PDF document page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document.

[0078] The content type includes at least one of text, vector graphics, images and tables, and the web page elements are used to form web pages.

[0079] The parsing of the PDF document is processed page by page. For example, starting from page 1, each time a page is obtained for parsing, the current parsed page information is updated for statistics.

[0080] After obtaining the PDF document, the content type of the page in the PDF document can be determined during the parsing process. For example, the type classification model can be combined to identify the content type of the page in the PDF document. Specifically, for each page in the PDF document, it is input into the type classification model to obtain the content type included in the page. Of course, in addition to the type classification model, other methods can also be used to determine the content type included in each page in the PDF document.

[0081] Different methods are used to parse the content types of the pages in the PDF document, so as to obtain the web page elements corresponding to the content types of the pages. Specifically, the parsing process of the content type can be understood as converting different content types into corresponding web page elements for subsequent rendering and display.

[0082] Step S103: Rendering is performed based on the web page elements to generate a web page corresponding to the PDF document.

[0083] The rendering method of web page elements is to display the web page elements according to the display format of the PDF document. For example, the font size and color of the web page must be consistent with the corresponding font size and color of the PDF document; the number of words in each line of the web page must be the same as the number of words in the corresponding line of the PDF document.

[0084] Furthermore, for the generated web pages, if similarity comparison is required, similar contents are also marked in the web pages when they are displayed, so as to facilitate quick comparison and positioning.

[0085] The PDF document conversion method provided in this embodiment parses the PDF document page by page to obtain the web page elements corresponding to the content type of each page in the PDF document, that is, to obtain the corresponding web page elements for different content types, and render the web page elements obtained after parsing, thereby generating the web page corresponding to the PDF document. By parsing the PDF document page by page, the processing concurrency caused by the full-text parsing can be avoided. At the same time, the page-by-page parsing can also ensure the accuracy of the parsing results and the accuracy of the subsequent rendering results. On this basis, it is ensured that the web page can truly represent the PDF document. Representing the PDF document by web page can facilitate the subsequent retrieval and comparative display of similar content on this basis.

[0086] In this embodiment, a PDF document conversion method is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 2 The flowchart of the method for converting a PDF document according to an embodiment of the present invention is described by taking the content type including text as an example. Figure 2 As shown, the process includes the following steps:

[0087] Step S201, obtain the PDF document to be converted and the page information of the PDF document. Figure 1 Step S101 of the illustrated embodiment will not be described in detail here.

[0088] Step S202: parsing the PDF document page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document.

[0089] The content type includes at least one of text, vector graphics, images and tables, and the web page elements are used to form web pages.

[0090] Specifically, if the content type includes text, the corresponding web page element includes a text element. Based on this, the above step S202 includes:

[0091] Step S2021, determining the current page to be parsed based on the page information.

[0092] As described above, the page information can be used to represent the number of pages currently being parsed, and based on this, the current page to be parsed in the PDF document can be accurately determined.

[0093] Step S2022, parse the text in the current page to be parsed, determine the hyphenation information and sentence segmentation information of the text, and obtain text elements.

[0094] Since the text includes characters and punctuation marks, on this basis, in order to ensure the consistency between the web page elements and the text, it is necessary to determine the hyphenation information and sentence segmentation information of the text when parsing the text. Furthermore, from the perspective of semantic understanding, the determination of hyphenation information and sentence segmentation information is also to facilitate the integrity of the annotated content during the subsequent similarity comparison.

[0095] In some optional implementations, the above step S2022 includes:

[0096] Step a1, determining feature information of each character in each line of text.

[0097] Step a2: based on the feature information, characters in the same line and adjacent lines are hyphenated or segmented, and hyphenation information and segmentation information are determined to obtain text elements.

[0098] The text in the PDF document can be text from a paragraph or a table, and there is no limitation on the source of the text. For each line of text in the current page to be parsed, the characteristic information of each character is determined, including but not limited to the position, size, format, etc. of the character.

[0099] For text in the same line, the distance between adjacent characters can be calculated to determine whether to connect the characters into a sentence or to break the sentence; or the angle between adjacent characters can be determined to determine whether to connect the characters into a sentence or to break the sentence, and so on.

[0100] For texts in different lines, since texts in different lines may be divided into paragraphs, the distance between the first character of the latter line of two adjacent lines and the page margin may be calculated. If the distance exceeds a preset value, it indicates that there is a paragraph break and a sentence break is required. Of course, other methods may also be used to determine the hyphenation information and the sentence break information to obtain the text element.

[0101] Character feature information is used to perform word ligation or sentence segmentation on the same line and adjacent lines respectively, and accurate display of characters is ensured by word ligation or sentence segmentation.

[0102] In some optional implementations, the above step a2 includes:

[0103] Step a21, for characters in the same row, calculate the association degree between two adjacent characters based on the feature information.

[0104] Step a22, if the correlation degree is greater than a preset correlation value, the two adjacent characters are combined to form a ligature information, otherwise, a sentence is segmented between the two adjacent characters to form a sentence segmentation information.

[0105] Step a23, for characters in adjacent rows, calculate a first page margin of a first character in a first adjacent row and a second page margin of a last character in a second adjacent row based on the feature information, the second row being located above the first row.

[0106] Step a24, if the difference between the first page margin and the second page margin is less than the preset margin value, the first character of the first line and the last character of the second line are combined to form the ligature information, otherwise the first character of the first line and the last character of the second line are segmented to form the segmentation information.

[0107] For characters in the same row, the feature information of each character has been known in the above description. When calculating the association degree, it is necessary to combine the feature information of adjacent characters for processing.

[0108] For example, the degree of association is represented by the angle between adjacent characters. For the tth character, its feature information forms a feature vector v t =[x t ,y t ,w t ,h t ,Style t ], where (x t ,y t ) indicates the coordinate information of the lower left corner of the tth character, (w t ,h t ) indicates width and height, Style t is a hot unique format encoding representing the style. For the adjacent t+1th character, its feature information can also form a feature vector v t+1 =[x t+1 ,y t+1 ,w t+1 ,h t+1 ,Style t+1 ]. Then, the angle between the two feature vectors is calculated. If the angle is less than the preset angle, the two feature vectors are considered to be parallel, that is, the two characters should be connected together. The preset angle is set to solve the error tolerance of some character widths and heights. In the case where the angle represents the degree of association, the smaller the angle, the greater the degree of association between two adjacent characters.

[0109] Based on this, if the correlation between two adjacent characters in the same row is greater than a preset correlation, it is considered that the two adjacent characters should be connected together to form ligature information; otherwise, it indicates that there is a segmentation between the two adjacent characters, forming segmentation information.

[0110] For characters in adjacent lines, since text processing is from left to right and from top to bottom, the next line between two adjacent lines is called the first line, and the previous line between two adjacent lines is called the second line. First determine the first character of the first line and the last character of the second line, then determine the distance between the first character and the nearest margin (left margin) to obtain the first margin, and the distance between the last character of the second line and the margin corresponding to the text direction (right margin) to obtain the second margin.

[0111] The difference between the first page distance and the second page margin is calculated. If the difference is less than the preset margin value, it means that the two characters need to be linked into a sentence, that is, the first character of the first line and the last character of the second line form the link information; otherwise, the first character of the first line and the last character of the second line are segmented to form the segmentation information. The preset margin value may be the maximum value of the widths of the two characters.

[0112] For example, if the coordinate y of the first character in the first row is t The y coordinate of the last character of the second line t-1 The difference is greater than max{w t ,w t-1}, it will determine whether the difference between the left margin of the current text t and the right margin of the previous text t-1 is less than max{w t ,w t-1 If it is less than , the sentence will be connected, otherwise it will be broken.

[0113] Using different methods to process the hyphenation or sentence segmentation for the same line and adjacent lines can further ensure the accuracy of the obtained hyphenation information and sentence segmentation information.

[0114] In some optional implementations, if the content type includes vector graphics, the web page element includes a vector graphics element. Based on this, the above step S202 includes:

[0115] Step a1, extracting line information of the vector graphics in the current page to be parsed.

[0116] Among them, the current page to be parsed is determined based on the page information.

[0117] Step a2: determining the fill area of ​​the vector graphic based on the line information.

[0118] Step a3, filling the fill area with color to obtain a vector graphic element.

[0119] Vector graphics are generally used to represent the watermark in the current page to be parsed. For the vector graphics, its line information is extracted. The closed area surrounded by the lines can be determined by combining the odd-even rule or the non-zero winding number rule to obtain the filled area of ​​the vector graphics. Then the fill is filled with color to obtain the vector graphics element. Among them, if the watermark is filled with gray, the filled area is filled with gray to ensure that the format of the vector graphics element is consistent with the format of the vector graphics in the PDF document.

[0120] Character feature information is used to perform word ligation or sentence segmentation on the same line and adjacent lines respectively, and accurate display of characters is ensured by word ligation or sentence segmentation.

[0121] In some optional implementations, if the content type includes an image, the web page element includes an image element. Based on this, the above step S202 includes:

[0122] Step b1, extracting the image in the current page to be parsed and determining the image format of the image. The current page to be parsed is determined based on the page information.

[0123] Step b2, parsing the image according to the image format to obtain image elements.

[0124] For the image in the current page to be parsed, since different images have different image formats, including but not limited to jpg, png, wmf, etc., corresponding parsing is performed for different image formats to obtain image elements.

[0125] Furthermore, the extracted images are compressed before being parsed, thereby reducing the storage space occupied by the images and reducing the bandwidth pressure of the image similarity analysis service during subsequent similarity comparisons.

[0126] For images in PDF, the image format is determined and then the image elements are obtained by parsing the image based on the image format, thus ensuring the consistency between the image elements and the PDF document.

[0127] In some optional implementations, if the content type includes a table, the web page element includes a table element. Based on this, the above step S202 includes:

[0128] Step c1, extracting line segments of a table in the current page to be parsed, and determining position information of each line segment in the current page to be parsed. The current page to be parsed is determined based on page information.

[0129] Step c2: Generate a table element of the current page to be parsed based on the position information of each line segment.

[0130] For the table in the current page to be parsed, it is parsed as line segments, but there is no real table element. Specifically, for the table, since the text in the table is parsed using the text processing method, and the line segments in the table do not need to be compared for similarity, therefore, for the line segments in the table, its position information needs to be accurately determined, so as to ensure the consistency between the table element and the table in the PDF document.

[0131] Based on this, for the line segments of the table in the current page to be parsed, its position information in the current page to be parsed needs to be determined during the parsing process, so as to generate the table elements of the current page to be parsed based on the position information of each line segment.

[0132] Step S203: Rendering is performed based on the web page elements to generate a web page corresponding to the PDF document. Figure 1 Step S103 of the illustrated embodiment will not be described in detail here.

[0133] The PDF document conversion method provided in this embodiment determines the current page to be parsed through page information, and can accurately obtain the PDF page that needs to be processed. At the same time, by determining the quantum information and sentence segmentation information of the text during parsing, the display consistency of the text elements and the text in the PDF is further guaranteed. The characteristic information of the characters is used to perform hyphenation or sentence segmentation processing on the same line and adjacent lines respectively, and the accurate display of the characters is guaranteed by hyphenation or sentence segmentation.

[0134] In this embodiment, a PDF document conversion method is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 3 is a flowchart of a method for converting a PDF document according to an embodiment of the present invention. Figure 3 As shown, the process includes the following steps:

[0135] Step S301, obtain the PDF document to be converted and the page information of the PDF document. Figure 1 Step S101 of the illustrated embodiment will not be described in detail here.

[0136] Step S302: parse the PDF document page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document.

[0137] The content type includes at least one of text, vector graphics, images and tables, and the web page elements are used to form web pages. Figure 2 Step S202 of the illustrated embodiment will not be described in detail here.

[0138] Step S303: Rendering is performed based on the web page elements to generate a web page corresponding to the PDF document.

[0139] Specifically, the above step S303 includes:

[0140] Step S3031: determining a rendering tag of the web page element based on the feature information of the web page element.

[0141] The characteristic information of the web page elements includes character styles and sentence characteristics. The sentence characteristics are determined based on the hyphenation information and sentence segmentation information of the text.

[0142] The rendering tags of web page elements are determined by combining the characteristic information of web page elements to ensure that the layout and format of the web page displayed after rendering are consistent with those in the PDF document. The rendering tags are used to represent the characteristic information of web page elements, including but not limited to character styles, sentence features, etc.

[0143] For example, a complete sentence is expressed by The tag is wrapped and has a unique ID. If the following two sentences in the document:

[0144] The winch and wellhead should be kept in a straight line, the operating room windows should be clean, the line of sight should be wide, and the communication should be good. During nighttime operations, the well site should be well lit.

[0145] The rendering tag needs to represent a complete sentence, and each complete sentence has a unique ID. For example, the rendering tag corresponding to the sentence "The winch and the wellhead should be kept in a straight line, the operating room glass window should be clean, the line of sight should be wide, and the communication should be good." can be <span id＝"1">; "During nighttime construction, lighting should be guaranteed at the well site." The corresponding rendering tag for this sentence can be <span id＝"2">.

[0146] For another example, in the first sentence, the font color of "straight line" is red, so its corresponding rendering tag can be <span style＝"color:red；">; The rest of the font colors are black, then the corresponding rendering tags can be<spanstyle="color:black;"> .

[0147] For another example, if the above two sentences belong to the same paragraph, they can be Tags to represent paragraphs.

[0148] Step S3032: Structuring the web page elements based on the rendering tags to obtain structured information.

[0149] The structured processing process can be considered as integrating the rendering tags with the web page elements, that is, wrapping the web page elements with the rendering tags to obtain structured information.

[0150] Continuing with the above example, by wrapping the sentence with rendering tags, the resulting structured information can be:

[0151] <span id＝"1"> The winch and wellhead should be kept in a straight line, the glass windows of the operating room should be clean, the line of sight should be wide, and the communication should be good. <span id＝"2"> During nighttime construction work, lighting should be ensured at the well site. ;

[0152] Under the premise of the statement wrapping described above, the content with the same style is passed After the label is wrapped and combined with the font color, the resulting structured information can be:

[0153] <span id＝"1"> <span style＝"color:black；"> The winch and wellhead should be kept <span style＝"color:red；"> Straight line <spanstyle="color:black;"> , the operating room has clean glass windows, wide vision and good communication. <span id＝"2"> <span style＝"color:black；"> During nighttime construction work, lighting should be ensured at the well site. .

[0154] Among them, wrapping a complete sentence Tags have ID attributes to distinguish different styles The tag does not contain an ID attribute.

[0155] Furthermore, a complete paragraph is passed The tag is wrapped and has a unique ID attribute. On this basis, the structured information obtained can be:

[0156] <div id＝"p_1"> <span id＝"1"> <span style＝"color:black；"> The winch and wellhead should be kept <span style＝"color:red；"> Straight line <spanstyle="color:black;"> , the operating room has clean glass windows, wide vision and good communication. <span id＝"2"><spanstyle="color:black;"> During nighttime construction work, lighting should be ensured at the well site. .

[0157] Furthermore, the complete content of a page is The tag completes the package, and each page has a unique ID attribute. Image content is obtained through Tags are referenced and have unique IDs.

[0158] In some optional implementations, the above step S3032 includes:

[0159] Step d1, detecting whether there are similar elements on the web page.

[0160] Step d2: when there are similar elements in the web page element, generate tag information of the web page element.

[0161] Step d3, structuring the web page elements based on the markup information and the rendering tags to obtain structured information.

[0162] During the rendering of web page elements, a search may also be performed in a database or data source to determine whether there are similar elements. The database stores documents to be compared, and the data source may be a document source available on the Internet or other data sources, etc., which are not limited in any way.

[0163] If an element similar to the web page element is retrieved, that is, it is determined that there is a similar element to the web page element, then the marking information of the web page element is generated. The marking information is used to mark the web page element as having a similar element. The marking information includes but is not limited to highlighting, or different fonts, colors, etc.

[0164] After the annotation information is determined, when the web page elements are structured, the marking information and the rendering tag processing are combined to obtain the structured information.

[0165] When generating web pages for web page elements, similarity comparison is also performed. If similar elements exist, tag information of the web page elements is generated, and the web page elements are structured in combination with rendering tags, thereby ensuring that similarity comparison identifiers can be displayed in the web page.

[0166] In some optional implementations, the above step d2 includes:

[0167] Step d21: when there are similar elements in the web page element, the first identification information corresponding to the web page element is associated with the second identification information corresponding to the similar element.

[0168] Step d22: determining the mark position and mark content of the web page element in the web page based on the first identification information and the second identification information.

[0169] The first identification information is used to represent the uniqueness of the web page element, and the second identification information is used to represent the uniqueness of the similar comparison element.

[0170] When there are similar elements in the web page elements, the first identification information corresponding to the web page element is associated with the second representation information corresponding to the similar element, so as to realize the associated display of the web page element and the similar element, so as to facilitate comparative viewing.

[0171] The marked position and marked content of the web page element in the web page are determined based on the first identification information and the second representation information. When the web page is displayed, the web page element and similar elements can be displayed at the same time and displayed using the corresponding identification information.

[0172] Step S3033: Render according to the structured information to generate a web page.

[0173] After the structured information is determined, it is rendered to display the web page on the browser interface.

[0174] The PDF document conversion method provided in this embodiment determines the rendering tag based on the characteristic information of the web page element, thereby ensuring that the determined rendering tag can represent the characteristics of the web page element, so that the structured processing result can ensure consistency with the PDF document.

[0175] As a specific application embodiment of the embodiment of the present invention, in the field of bidding, the PDF document to be converted can be a PDF document participating in the bidding. A target application is deployed in the electronic device, and the uploading of the PDF document is realized by interacting with the target application. After uploading the PDF document, it is converted according to the conversion method of the PDF document provided by the embodiment of the present invention, and similar elements are retrieved. When finally displayed on the browser interface, the web page elements and their corresponding similar elements can be displayed simultaneously on the same web page, and they are marked in the same way for easy comparison and viewing.

[0176] For example, Figure 4 An example of a web page is shown. The web page displays the comparative similarity of the PDF document to be converted and the number of web page elements with similar elements. In addition, the web page elements and their corresponding similar elements are also displayed. Figure 4 The web page elements and their corresponding similar elements are selected using text boxes.

[0177] This method can achieve high fidelity preservation of the original layout and style of PDF documents, including multiple elements such as text, images and watermarks. This ensures that the presentation effect of the document on the browser side is highly consistent with the original PDF document, which is convenient for users to view and operate. A comprehensive content extraction and comparison algorithm is used to independently extract and analyze the similarity of multiple content types such as text, images, and watermarks. Through the comprehensive analysis results, the accuracy of similarity detection can be improved, which is suitable for detecting similar content in documents. The web page on the browser side implements fast marking and positioning functions, allowing users to quickly find similar content in documents. The optimized algorithm design takes into account computational efficiency while ensuring high-fidelity rendering and accurate content detection. Through reasonable algorithm optimization and resource utilization, complex documents can be processed in a short time, which meets the processing needs of large-scale documents. This method supports comprehensive analysis of multiple content types (such as text, images, watermarks, etc.) in documents, and combines the feature information of these elements for similarity judgment. This multi-element comprehensive analysis method improves the recognition ability and accuracy of complex documents.

[0178] The application scenarios used in this solution are not only applicable to the bidding field described above, but can also be extended to other scenarios that require high-fidelity rendering of PDF documents and similar content detection, such as academic paper duplicate checking, copyright protection, etc. Therefore, its strong adaptability and practicality make it have a wide range of application prospects.

[0179] In this embodiment, a PDF document conversion device is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware of a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0180] This embodiment provides a PDF document conversion device, such as Figure 5 As shown, including:

[0181] The acquisition module 501 is used to acquire the PDF document to be converted and the page information of the PDF document.

[0182] The parsing module 502 is used to parse the PDF document page by page based on the page information to obtain the web page elements corresponding to the content type of each page in the PDF document. The content type includes at least one of text, vector graphics, images and tables. The web page elements are used to form web pages.

[0183] The rendering module 503 is used to perform rendering based on the web page elements to generate a web page corresponding to the PDF document.

[0184] In some optional implementations, if the content type includes text, the corresponding web page element includes a text element, and the parsing module 502 includes:

[0185] The page determination unit is used to determine the current page to be parsed based on the page information.

[0186] The text parsing unit is used to parse the text in the current page to be parsed, determine the hyphenation information and sentence segmentation information of the text, and obtain text elements.

[0187] In some optional implementations, the text parsing unit includes:

[0188] The feature information determination subunit is used to determine the feature information of each character in each line of text.

[0189] The text element determination subunit is used to perform hyphenation or sentence segmentation on characters in the same line and adjacent lines based on feature information, determine hyphenation information and sentence segmentation information, and obtain text elements.

[0190] In some optional implementations, the text element determination subunit includes:

[0191] The association degree calculation subunit is used to calculate the association degree between two adjacent characters based on feature information for characters in the same row.

[0192] The first determining subunit is used to form ligature information by combining two adjacent characters if the correlation degree is greater than a preset correlation value, and to perform sentence segmentation between the two adjacent characters to form sentence segmentation information otherwise.

[0193] The page margin determination subunit is used to calculate the first page margin of the first character in the first adjacent line and the second page margin of the last character in the second adjacent line based on the feature information for the characters in adjacent lines, and the second line is located above the first line.

[0194] The second determination subunit is used to, if the difference between the first page margin and the second page margin is less than a preset margin value, form the hyphenation information by combining the first character of the first line and the last character of the second line; otherwise, perform sentence segmentation between the first character of the first line and the last character of the second line to form sentence segmentation information.

[0195] In some optional implementations, if the content type includes vector graphics, the web page element includes a vector graphics element, and the parsing module 502 includes:

[0196] The line information extraction unit is used to extract line information of vector graphics in the current page to be parsed, and the current page to be parsed is determined based on the page information.

[0197] The filling area determination unit is used to determine the filling area of ​​the vector graphic based on the line information.

[0198] The color filling unit is used to fill the fill area with color to obtain a vector graphic element.

[0199] In some optional implementations, if the content type includes an image, the web page element includes an image element, and the parsing module 502 includes:

[0200] The image extraction unit is used to extract the image in the current page to be parsed and determine the image format of the image. The current page to be parsed is determined based on the page information.

[0201] The image parsing unit is used to parse the image according to the image format to obtain image elements.

[0202] In some optional implementations, if the content type includes a table, the web page element includes a table element, and the parsing module 502 includes:

[0203] The line segment extraction unit is used to extract the line segments of the table in the current page to be parsed and determine the position information of each line segment in the current page to be parsed. The current page to be parsed is determined based on the page information.

[0204] The table element generating unit is used to generate the table element of the current page to be parsed based on the position information of each line segment.

[0205] In some optional implementations, the rendering module 503 includes:

[0206] The rendering tag determination unit is used to determine the rendering tag of the web page element based on the feature information of the web page element. The feature information of the web page element includes character style and sentence features. The sentence features are determined based on the hyphenation information and sentence segmentation information of the text.

[0207] The structured processing unit is used to structure the web page elements based on the rendering tags to obtain structured information.

[0208] The information rendering unit is used to render according to the structured information to generate a web page.

[0209] In some optional implementations, the structured processing unit includes:

[0210] The detection subunit is used to detect whether there are similar elements on the web page.

[0211] The tag information generating subunit is used to generate tag information of a web page element when there are similar elements among the web page elements.

[0212] The structured processing subunit is used to structure the web page elements based on the markup information and the rendering tags to obtain structured information.

[0213] In some optional implementations, the marking information includes a marking position and a marking content; and the marking information generating subunit includes:

[0214] The associating subunit is used to associate the first identification information corresponding to the web page element with the second identification information corresponding to the similar element when there are similar elements in the web page element.

[0215] The third determining subunit is used to determine the marked position and marked content of the web page element in the web page based on the first identification information and the second identification information.

[0216] The first identification information is used to represent the uniqueness of the web page element, and the second identification information is used to represent the uniqueness of the similar comparison element.

[0217] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0218] The PDF document conversion device in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and a memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0219] The embodiment of the present invention also provides a computer device having the above Figure 5 The PDF document shown is converted by the device.

[0220] See also Figure 6 , Figure 6 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Figure 6 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 6 A processor 10 is taken as an example.

[0221] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0222] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0223] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0224] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0225] The computer device also includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means. Figure 6 The example of connecting through bus is taken in the following.

[0226] The input device 30 can receive input digital or character information, and generate key signal input related to the user settings and function control of the computer device, such as a touch screen, a keypad, a mouse, a track pad, a touch pad, an indicator bar, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED) and a tactile feedback device (e.g., a vibration motor), etc. The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display and a plasma display. In some optional embodiments, the display device can be a touch screen.

[0227] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0228] A part of the present disclosure may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present disclosure through the operation of the computer. Those skilled in the art should understand that the existence of computer program instructions in computer-readable media includes, but is not limited to, source files, executable files, installation package files, etc., and accordingly, the way in which computer program instructions are executed by a computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to the computer.

[0229] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for converting a PDF document. It is characterized in that The method comprises: Obtaining the PDF document to be converted and page information of the PDF document; Parsing the PDF document page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document, wherein the content type includes at least one of text, vector graphics, images, and tables, and the web page elements are used to form a web page; Rendering is performed based on the web page elements to generate a web page corresponding to the PDF document.

2. The method according to claim 1, It is characterized in that If the content type includes text, the corresponding web page element includes a text element, and the PDF document is parsed page by page based on the page information to obtain web page elements corresponding to the content type of each page, including: Determine the current page to be parsed based on the page information; The text in the current page to be parsed is parsed to determine the hyphenation information and sentence segmentation information of the text to obtain the text element.

3. The method according to claim 2, It is characterized in that The step of parsing the text in the current page to be parsed, determining the hyphenation information and sentence segmentation information of the text, and obtaining the text element includes: Determining feature information of each character in each line of text; Characters in the same row and adjacent rows are hyphenated or segmented based on the feature information, the hyphenation information and the segmentation information are determined, and the text element is obtained.

4. The method according to claim 3, It is characterized in that The step of hyphenating or segmenting the text in the same line and adjacent lines based on the feature information, determining the hyphenation information and segmentation information, and obtaining the text element comprises: For characters in the same row, calculating the degree of association between two adjacent characters based on the feature information; If the correlation degree is greater than a preset correlation value, the two adjacent characters are combined into a ligature information, otherwise, a sentence is segmented between the two adjacent characters to form a sentence segmentation information; For characters in adjacent rows, calculating a first page margin of a first character in a first row of the adjacent rows and a second page margin of a last character in a second row of the adjacent rows based on the feature information, the second row being located above the first row; If the difference between the first page margin and the second page margin is less than the preset margin value, the first character of the first line and the last character of the second line are used to form hyphenation information; otherwise, a sentence is broken between the first character of the first line and the last character of the second line to form sentence breaking information.

5. The method according to claim 1, It is characterized in that If the content type includes vector graphics, the web page element includes a vector graphics element, and the PDF document is parsed page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document, including: Extracting line information of the vector graphic in a current page to be parsed, wherein the current page to be parsed is determined based on the page information; Based on the line information, determining a fill area of ​​the vector graphic; Color filling is performed in the filling area to obtain the vector graphic element.

6. The method according to claim 1, It is characterized in that If the content type includes an image, the web page element includes an image element, and the PDF document is parsed page by page based on the page information to obtain web page elements corresponding to the content type of each page in the PDF document, including: Extracting an image from a current page to be parsed and determining an image format of the image, wherein the current page to be parsed is determined based on the page information; The image is parsed according to the image format to obtain image elements.

7. The method according to claim 1, It is characterized in that If the content type includes a table, the web page element includes a table element, and the PDF document is parsed page by page based on the page information to obtain the web page elements of each page, including: Extracting line segments of the table in the current page to be parsed, and determining position information of each line segment in the current page to be parsed, wherein the current page to be parsed is determined based on the page information; Based on the position information of each line segment, a table element of the current page to be parsed is generated.

8. The method according to any one of claims 1 to 7, It is characterized in that The rendering based on the web page elements to generate a web page corresponding to the PDF document includes: Determining a rendering tag of the web page element based on feature information of the web page element, wherein the feature information of the web page element includes character style and sentence features, and the sentence features are determined based on hyphenation information and sentence segmentation information of the text; Structuring the webpage elements based on the rendering tags to obtain structured information; Rendering is performed according to the structured information to generate the web page.

9. The method according to claim 8, It is characterized in that The structuring of the webpage elements based on the rendering tags to obtain structured information includes: Detecting whether there are similar elements to the web page elements; When there are similar elements to the web page element, generating tag information of the web page element; Based on the marking information and the rendering tag, the web page element is structured to obtain structured information.

10. The method according to claim 9, It is characterized in that The marking information includes a marking position and a marking content; When there are similar elements to the web page element, generating tag information of the web page element includes: When there are similar elements to the webpage element, associating the first identification information corresponding to the webpage element with the second identification information corresponding to the similar element; Based on the first identification information and the second identification information, determining a marking position and marking content of the web page element in the web page; The first identification information is used to represent the uniqueness of the web page element, and the second identification information is used to represent the uniqueness of the similar comparison element.

11. A PDF document conversion device, It is characterized in that The device comprises: An acquisition module, used to acquire the PDF document to be converted and page information of the PDF document; A parsing module, configured to parse the PDF document page by page based on the page information, and obtain web page elements corresponding to the content type of each page in the PDF document, wherein the content type includes at least one of text, vector graphics, images, and tables, and the web page elements are used to form a web page; The rendering module is used to render based on the web page elements to generate a web page corresponding to the PDF document.

12. A computer device, It is characterized in that include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the PDF document conversion method according to any one of claims 1 to 10 by executing the computer instructions.

Images