Digital image watermarking detection method based on robust difference

Abstract

The invention discloses a digital image watermarking detection method based on robust difference. The digital image watermarking detection method based on robust difference includes the steps: performing secondary non down-sampling Contourlet transformation on a host image, in the same direction, making difference between the father coefficients and the sub coefficients, of two scales, being obtained through decomposition, obtaining the difference sub-bands, and selecting the difference sub-band with the highest energy as the carrier; by means of a multiplicative method, performing watermarking embedding, and obtaining an image with watermarking through reconstruction; extracting the watermarking, performing modeling of a statistic model on the difference sub-band with the watermarking bymeans of a Cauchy distribution probability density function, obtaining a shape parameter Gamma and a positional parameter, and performing parameter estimation on the difference sub-band coefficient with the watermarking by means of a sample fractile estimation method; and according to the decision criterion, constructing a local optimal LMP detector and a Rao detector, and utilizing the decision threshold to determine whether the watermarking exists or not.

Description

technical field [0001] The invention belongs to the technical field of copyright protection of digital images, and relates to an image watermark detection method based on Cauchy distribution statistical modeling of difference, in particular to an image watermark detection method based on robust difference. Background technique [0002] The rapidly developing high-tech era gradually affects people's work and daily life. The use of digital multimedia products (such as images, audio, video, etc.) can be seen everywhere, and people can use various convenient channels to obtain more multimedia resources. However, because network communication is a double-edged sword, it can not only spread beneficial information, but also can spread harmful information, which brings great inconvenience to people's life. Illegal dissemination not only violates the rights and interests of copyright owners, but also causes society's distrust of multimedia information security. Image watermarking te...

AI Technical Summary

Problems solved by technology

Detecting whether there is a watermark is a crucial step in watermark detection technology, but there are still many deficiencies: first, there is no in-depth analysis of whether the current transformation method can better capture image features; second, the selected distribution is not considered Whether the function is an optimal model; Third, in terms of improving the performance of the detector, most algorithms use the log-likelihood ratio to construct the detector, and the algorithms that use other statistical strategies to construct the detector are extremely scarce

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