Multi-watermark technology based on network information theory

Abstract

The invention provides a method for achieving a plurality of watermarks. The basic principle is to count the process for achieving the plurality of the watermarks as a multi-user communication process containing side information and make use of a correlated source coding theorem, a multi-user communication theory and the like to perform theoretical analysis so as to obtain the side information available in the communication process. The method comprises two processes of watermark embedment and extraction and comprises the following steps: using maximum linear correlation values between a corresponding subblock of a carrier and each watermark coding signal as a selection embedding position of the side information, a detection threshold value and the embedment strength; making use of a perceptual model to perform perceptual forming on watermark signals; adjusting the watermark embedment strength according to the linear correlation values between the fixed carrier and the watermark coding signals so as to obtain a carrier containing a watermark; and performing detection through a linear correlation detector. The proposal can effectively avoid the mutual interference among the plurality of the watermarks, has better robustness, and can be applied to the copyright managements in occasions of network publishing, operation trailing and the like.

Description

technical field [0001] The invention belongs to the field of communication and information systems, and relates to information theory, coding, image processing and other technologies, in particular to digital image watermarking technology. Background technique [0002] Digital watermarking, as a technology arising from copyright protection, is regarded as the "last line of defense" for multimedia security, and plays an important role in the transmission and preservation of digital works. If only one piece of information is embedded in a digital medium, it is called a single watermark; if two or more pieces of information are embedded, it is called a multi-watermark. With the increasingly widespread application of work transactions, operation tracking, and online publishing in the network environment, the demand for multi-watermark technology is increasingly urgent. Multiuser communication processes in network information theory. [0003] Multi-watermarking technology has a...

AI Technical Summary

Problems solved by technology

When detecting watermarks, since each watermark is orthogonal to each other, it will not interfere with each other, but this method can only detect the existence of watermark information, and each watermark must be orthogonal or approximately orthogonal, which is practical. restricted in application

[0007] To sum up, most of the existing multi-watermarking methods are simple deformations of the single-watermarking algorithm, and they need to be further developed in terms of capacity, effectiveness, and robustness.

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