Robust Blind Watermarking to Secure Color Medical Images Using Multidimensional-FFT Fusing LFSR-Encryption and LZW Compression

This paper offers a new robust-blind watermarking scheme for medical image protection. In the digital era, protecting medical images is essential to maintain the confidentiality of patients and data reliability. Robust blind watermarking has surfaced as a practical option for secure image authentication and copyright protection. A new plan uses the multidimensional fast Fourier transform (MD-FFT) and combines LZW compression with linear feedback shift register (LFSR) encryption. Nevertheless, current watermarking methodologies frequently encounter difficulties balancing endurance, invisibility, and payload capacity. Numerous methodologies inadequately offer robust protection against diverse threats while ensuring imperceptibility and effective data management. The motivation behind this successful integration is to reinforce invisibility and sturdiness. The host image is initially divided into four equal portions for rapid processing, followed by encryption using the LFSR method to increase robustness. The Multi-FFT is applied to the encrypted parts to enhance their visual invisibility. The watermark is first encoded using LZW compression, then scrambled with Arnold encryption before being embedded in the modified MD-FFT magnitudes, strengthening the protection level. The watermark is fully and blindly extracted without referencing the host image. Compared to similar methods, the proposed scheme maintains a fundamental tradeoff between robustness and visual imperceptibility against many commonly encountered attacks. The extracted watermark remains original with minimal observable distortion. Empirical findings confirm that the proposed algorithm outperforms existing watermarking methods in terms of invisibility and robustness while maintaining an acceptable payload capacity.