Synchronous detection method of transformed digital watermark

Abstract

A method for synchronous detection of digital watermarking in transform domain, which uses chaotic pseudo-random sequence encryption and frequency spread watermark to embed into mid-high frequency coefficients of carrier image block DCT transform domain to form watermark-embedded image. The receiving end copies the spreading code matrix according to the key, and performs two-dimensional DCT inverse transformation on the elements except the protected part in the upper left corner to obtain the detection code matrix in the corresponding space domain. Geometric transformation is performed on the space-domain detection code matrix, so that each detection code matrix is ​​aligned with the corresponding watermark bit embedding position in the carrier image after the geometric attack. Corresponding bit watermark information is obtained by correlating the aligned detection code matrix with the carrier digital image, and the watermark information is restored after decryption and rearrangement. The invention realizes the synchronous detection of the digital watermark in the transformation domain under the attack of geometric transformation and the like by the exotic domain extraction of the watermark and the watermark tracking detection technology, and effectively improves the overall robustness of the watermark system under the conditions of signal processing such as compression and geometric attack.

Description

Technical field: [0001] The invention relates to a synchronous detection method of transform domain digital watermark, which is particularly suitable for synchronous detection of digital watermark in digital images, videos and other products under the condition of geometric transformation attack. Background technique: [0002] In recent years, with the popularization of computer and Internet technology, as well as the development of multimedia storage and transmission technology, the transmission and sharing of digital products has become very easy, but this has also brought a series of issues related to copyright disputes, such as a large number of digital products been illegally copied. In order to protect the interests of copyright owners, it is hoped that an effective method can be found to protect the intellectual property rights of these digital products. Digital watermarking is a technology that is suitable for copyright protection, release tracking and identity auth...

AI Technical Summary

Problems solved by technology

The digital watermarking algorithm in the space domain is often less robust to compression, filtering, and noise pollution than the algorithm in the transform domain, and the subjective quality of the digital image embedded with the watermark is also slightly worse than the method in the transform domain.

If the watermark synchronization method based on the calibration signal is synchronized to the existing transform domain watermark method, the effect is not satisfactory

[0012] To sum up, among the current robust watermarking algorithms: the transform domain algorithm has strong robustness to compression, noise pollution, etc., but is less robust to geometric transformation attacks; the space domain design is robust to geometric transformation attacks. Stick watermark, which has certain robustness to geometric transformation, but does not have the superiority of transform domain algorithm

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