A completely blind digital watermarking method with copyright protection and tampering location functions

Abstract

The invention discloses a full-blind digital watermarking method with functions of copyright protection and tampering positioning. It divides the approximate sub-image of the original gray image into non-overlapping 8×8 sub-blocks, and divides each sub-block into 4×4 sub-blocks. region; discrete cosine transform is performed on each region; feature watermarks and self-embedded feature watermarks are created according to the discrete cosine transform coefficient matrix of different regions; each sub-block in each sub-block in the approximation sub-graph of the watermark image is extracted in the same way Perform discrete cosine transform on each area; then blindly extract the feature watermark and authentication watermark according to the discrete cosine transform coefficient matrix of different areas; calculate the normalized correlation coefficient between the feature watermark and authentication watermark for copyright protection, and compare the feature watermark and authentication watermark bit by bit. The certified watermark realizes blind tampering location; the advantage is that only one digital watermark can be embedded to realize the dual functions of copyright protection and tampering location, and the original image and any information of the original digital watermark are not needed when extracting the watermark, which can realize the blind detection of the watermark.

Description

technical field [0001] The invention relates to a digital media information security technology, in particular to a full-blind digital watermarking method with functions of copyright protection and tampering positioning. Background technique [0002] With the rapid development of digital media and network technology, digital watermarking technology has become an effective means of media copyright protection and content integrity authentication. However, most of the existing digital watermarking technologies are single watermarking algorithms, which often have the limitation of a single function, that is, only copyright protection or content authentication can be achieved. Obviously, the digital watermarking algorithm with multi-function has a stronger demand in practical application. [0003] Multifunctional digital watermarking refers to embedding watermarks with different properties in the same digital image to achieve different application purposes. For example, a visib...

AI Technical Summary

Problems solved by technology

Obviously, compared with the single watermarking algorithm, the simultaneous embedding of double watermarks will inevitably lead to a decline in image quality; interference, thus affecting the extraction effect of the subsequent watermark

In addition, in order to realize functions such as copyright protection and content authentication, the correlation measurement and comparison between the extracted robust watermark and fragile watermark and the original digital watermark are required, and the blind detection of digital watermark cannot be realized.

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