A method for encrypting and decrypting printed text in invisible office

Abstract

The invention provides a text encryption and decryption method for invisible office printing, which can realize strong anti-interference ability, consume very little hardware resources, and have less requirements on the text itself. The present invention proposes a relatively simple and feasible hidden data encryption method. The algorithm is relatively simple. By performing invisible encryption on the document, the time, place, person, unit information and other content can be effectively embedded in the document. Once the document is illegally leaked, it can quickly Effectively locate and query leaking units or personnel. The hardware consumes very little resources; there are few requirements for the text itself, and only a small amount of text or characters can be used to encrypt information; this method has strong anti-interference ability and can effectively resist the impact of text printing on encryption; high concealment , is not easy to be found, which is beneficial to query or trace after the event; there is no visible change to the original manuscript, which is conducive to the use and reading of the manuscript.

Description

technical field [0001] The invention relates to the technical field of printing text encryption, in particular to a method for encrypting and decrypting printed text in an invisible office. Background technique [0002] In today's highly developed science and technology, information security has been paid more and more attention by people. In all walks of life, inside or secret information exists. When the information is printed out in the form of manuscripts and distributed to various relevant units or functional departments, how to effectively manage and control the information is an important issue faced by each unit or department. Especially when information is leaked, how to effectively trace and query, and plug the loopholes of information leaks requires very technical means. However, all printing and copying products currently on the market use explicit watermark information to mark manuscripts. Obviously, this cannot completely effectively prevent information leaka...

AI Technical Summary

Problems solved by technology

[0004] Although there are many existing hidden digital encryption technologies, most of them have a common disadvantage: the encrypted information is only effective for high-definition electronic digital images themselves, when disturbed by the outside world, especially when the printer prints out , when the response non-uniformity of the photosensitive material of the toner cartridge itself and the non-uniformity of the toner itself interfere with the original data, the encrypted information is very easy to be destroyed, thus losing the encryption effect

However, due to the use of unimportant pixel bits of the image, the robustness of the algorithm is poor, and the watermark information is easily destroyed by filtering, image quantization, and geometric deformation operations.

However, using the data encryption technology based on DCT transformation, although under certain conditions, the anti-interference ability has been improved to a certain extent, but its disadvantages are 1) a large amount of calculation and a huge consumption of hardware resources; 2) the image and The complexity of the document has certain requirements, that is, the texture of the image should be relatively rich, because this technology mainly changes the frequency domain of the image, and encrypts the data of the high-frequency, medium-frequency, and low-frequency parts

But obviously, when the document or image information is less, the converted spectrum is relatively single, and data encryption cannot be effectively carried out

At the same time, it is also susceptible to interference

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