Method and device for embedding and extracting multiple digital watermarks in documents

Abstract

The invention relates to a document multiple digital watermarking insertion method and device, and a document multiple digital watermarking extraction method and device. The document multiple digital watermarking insertion method comprises the following steps of obtaining an original watermarking message, a secret key and a document to be processed, wherein the original watermarking message is input by a user; calculating a summary message in the original watermarking message, generating new watermarking messages, storing the original watermarking message and the new watermarking messages into a database as a database record together, dividing characters in the document into two layers, obtaining the number of sets of the new watermarking messages to be inserted into the first layer of the document according to the total number of the characters of the first layer of the document and the length of the digits of the new watermarking messages, inserting the multiple sets of new watermarking messages into the property digits of the first layer of the document sequentially from front to back, and inserting the multiple sets of new watermarking messages into the property digits of the second layer of the document sequentially from back to front. Based on the character property of the document of the Word format, safety is improved due to the use of the secret key, robustness is enhanced due to repeated insertion, and watermarking capacity is improved due to multiple insertions.

Description

technical field [0001] The invention relates to the field of digital watermarks, in particular to a method and device for embedding and extracting multiple digital watermarks of documents. Background technique [0002] In recent years, with the rapid development of multimedia and network technology, the copyright protection of digital works has become a hot topic in the current academic research. As an important research direction of information hiding technology, digital watermarking has great value in the copyright protection of text, video, audio and other multimedia. Digital watermarking is to embed serial number, text, image logo and other copyright information into multimedia data to play the role of copyright protection, secret communication, authenticity identification of data files and product logo. [0003] The existing text watermarking methods with high usability mainly include format-based text watermarking and natural language-based text watermarking. Format-...

AI Technical Summary

Problems solved by technology

However, for standard files, this method may change the semantics due to its strict format requirements, so it is not suitable for files with strict format requirements

In addition, because the computer's processing of natural language is not mature enough, it has become the bottleneck of natural language text watermarking technology.

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