Security watermark algorithm combining cryptography

Abstract

The invention mainly aims to solve the security attack problem of watermarks, and provides a high-security watermark algorithm by further referring to an encryption mechanism and a dual-watermark mechanism on the basis of making full use of a password thought and a theory of error-correcting codes specific to different security attack characteristics. In the algorithm, a watermark embedding link is partitioned into a private watermark embedding part and a public watermark embedding part. Private watermarks are embedded through an adaptive spatial domain watermark algorithm; original watermarks are encrypted by further referring to a carrier feature sequence on an information layer; error correction coding is performed on an encrypted sequence through Hamming error correcting coding in order to cope with copy attacks; and watermark embedding positions and embedding strengths are encrypted on a transmission layer in order to cope with homologous detection attacks. Public watermark embedding is finished through an adaptive watermark algorithm which has high robustness and is based on DCT (Discrete Cosine Transform), so that detection of collusion attacks can be realized. As proved by a test result, the problem of security attacks to the watermarks can be well solved.

Description

technical field [0001] The invention belongs to the field of communication and information systems, and relates to technologies such as information theory, covert communication, cryptography and coding, image processing, and in particular to digital image watermarking technology. Background technique [0002] As an important carrier of information dissemination, digital media is widely disseminated on the Internet, creating huge economic and social value for the society. Because digital media is easy to copy, tamper, imitate, distribute, and difficult to track, there are more and more infringements against digital media, which have brought huge economic losses to the country and individuals. It is in this environment that digital watermarking technology emerges at the historic moment. Usually, copyright protection watermarking technology is to permanently embed the information identifying the owner of the work into the work, which is invisible and difficult to remove. In t...

AI Technical Summary

Problems solved by technology

[0009] The proposal and application of the double watermark mechanism is mainly to solve the problem of collusion attack, and its watermark system model is different from the traditional watermark system model

Images