Method for previewing PDF file, method for generating PDF file and method for processing PDF file

Abstract

The invention provides a method for previewing a PDF file, a method for generating the PDF file and a method for processing the PDF file. The previewing method comprises the following steps of analyzing an original PDF file to obtain a text, a pattern, a font and a picture in the original PDF file; randomly scrambling the order of the obtained text and the text part in the style in an absolute positioning manner to form an out-of-order file; storing out-of-order files formed by each page of PDF, and associating and storing font files and picture files corresponding to characters in the page ofPDF; obtaining input PDF preview information; querying a stored out-of-order file according to the PDF preview information to obtain a PDF or a plurality of PDF pages on which the PDF preview information resides; according to the absolute positioning mode, obtaining the order of the characters, obtaining font files and picture files corresponding to the characters and reorganizing the font filesand picture files; and displaying the PDF or multi-page PDF which satisfies the preview information of the PDF in the form of PDF at the browser end.

Description

technical field [0001] The invention relates to a file processing technology, and in particular to a method for previewing, generating and processing a PDF file. Background technique [0002] The PDF file (Portable Document Format) is a file format developed by Adobe Systems for file exchange in a manner independent of applications, operating systems, and hardware. Currently, most of the content or information on the Internet is displayed to users in the form of PDF files. Users need to preview or edit PDF files during use. [0003] For the preview, there are mainly three ways at present. The first way is that the user can read the content of the document by downloading the entire PDF file. In this method, a complete PDF must be downloaded. The file may be too large and the user's permission to read it cannot be controlled. At the same time, it is very easy to be crawled by crawlers, which is not conducive to copyright protection. The second method is that the server conv...

AI Technical Summary

Problems solved by technology

In this method, the complete PDF must be downloaded, the file may be too large and the user’s permission to read it cannot be controlled, and it is very easy to be crawled by crawlers, which is not conducive to copyright protection

The second method is that the server converts the PDF into a picture to provide a preview. In this method, when the PDF file is converted into a picture, the transmission traffic and time will be wasted if the picture is too large.

The third method is that the server converts the PDF into plain text to provide a preview. When converted into plain text, the original appearance of the PDF file cannot be restored, which may cause difficulties for users to read.

[0004] For editing, the first is to use the official PDF reader to edit the PDF. The official PDF reader edits the PDF process is cumbersome, the operability is poor, and the computer memory occupied by its installation is also very large, and it is very difficult to use. inconvenient

The second method is to convert the PDF into word format for editing, and then regenerate the PDF. The code for generating PDF in this way is too cumbersome, not flexible enough, and difficult to form a complete solution

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