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Improved Watermarking Algorithm Based on SURF and SVD with wavelet transformation Against Geometric Attacks

The application of digital medical images occupies an important position in the diagnostic process with the promotion of computer technology in the medical field. The resulting copyright and tampering issues have also attracted increasing attention. Digital watermarking technology can provide powerful technical support for copyright protection and tamper detection of medical images. Aiming at the problems of small embedding capacity and weak resistance to geometric attacks of digital image watermarking algorithms, a digital watermarking algorithm based on accelerated robust feature algorithm (SURF), redundant discrete wavelet transform (RDWT) and singular value decomposition (SVD) was proposed. The feature points are extracted using the rotation and translation invariance of the SURF algorithm, and the RDWT and SVD transforms and inverse transforms of the carrier image and the watermark image are performed to achieve the embedding and extraction of the watermark. A random sampling consistency algorithm is introduced to optimize the feature point matching results. Experimental results show that the algorithm improves the embedding watermark capacity and effectively enhances the robustness against geometric attacks. At the same time, compared with similar algorithms, the amount of additional information in this algorithm is a fixed value, which can better meet the detection and recovery requirements of medical images.