Robust image watermark method based on local Tchebichef moment

Abstract

The invention discloses a robust image watermark new method based on a local Tchebichef moment, mainly solving the problem that a watermark arithmetic based on image characteristic at present can not effectively resist general image processing and geometry attack simultaneously. The method comprises the steps as follows: firstly, extracting characteristic points of an original image by utilizing a Harris-Laplace detection operator, and obtaining a group of stable and mutually independent round characteristic areas through characteristic selection; then obtaining a geometrically unchanged round characteristic area through principle direction alignment; and finally, calculating the Tchebichef moment in an inscribed square image block of the round characteristic area, and embedding a watermark through dithering quantized modulation to modify an amplitude value with low-level Tchebichef moment. In detection, the modified low-level Tchebichef moment is obtained through the dithering quantized modulation, and a minimum distance is utilized to realize the blind extraction of the watermark. The invention has favorable nonvisibility, excellent robust performance for general image processing, geometry attach and combined attach and superior performance to similar methods and can be used for copyright protection for different images.

Description

technical field [0001] The invention relates to the technical field of information security, in particular to a digital image watermark embedding and blind detection method, which can effectively resist geometric attacks and conventional image processing, and can be used for copyright protection, ownership verification, and copying of digital image works on the Internet. control field. Background technique [0002] The digitization of multimedia data such as image, video, audio, etc. provides great convenience for the access of multimedia information, and also greatly improves the efficiency and accuracy of information expression. With the increasing popularity of the Internet, the exchange of multimedia information has reached an unprecedented depth and breadth, and its release forms are becoming more and more abundant. People can easily copy, download and distribute digital media through the Internet. On the one hand, it provides convenient conditions for people's life a...

AI Technical Summary

Problems solved by technology

[0007] The object of the present invention is to provide a kind of robust image watermarking method based on local Tchebichef moment (Local Techebichef Moments, LTMs), to overcome above-mentioned watermarking method util

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