An optimized ECG copyright protection technique and its feature authentication

Abstract

The safe and dependable transfer of biomedical signals through smart medical devices is made possible by digital watermarking. This work proposes a reliable, secure, optimized watermarking technique for Electrocardiogram (ECG) data. Patient ID is used as watermark and pre-processed with 1-level lifting wavelet transform (LWT) before embedding. The suitable scaling factor is obtained using the Harris Hawks optimization (HHO) technique to balance the trade-off between robustness and imperceptibility. Watermark is encrypted using Henon map before embedding to provide security. QR decomposition and randomized singular value decomposition (RSVD) are applied to host ECG's horizontal and vertical sub-bands. Principal components (PC’s) are modified to embed the watermark instead of singular values, and thus, the proposed technique is free from false positive problems (FPP). The maximum Peak signal to noise ratio (PSNR) value obtained is 50.05 dB, and normalized correlation coefficient (NC) is 0.9975. The average percentage improvement in imperceptibility is 6.72 %, and in time complexity is 76.26 %. Comparison with existing ECG watermarking techniques establishes that the proposed ECG watermarking scheme outperforms in terms of robustness, imperceptibility, capacity, and computational complexity. Binary Robust Invariant Scalable Keypoints (BRISK) are used to verify the vital features of input ECG image to detect any undesired alteration.