Improvement of Digital Image Watermarking Algorithm Against Noise Attack Using Based On Dual-Tree Complex Wavelet Transform
Information security has become a critical requirement in the modern digital era, as it ensures the protection of sensitive data during transmission in practical applications. Numerous information security techniques have been proposed for image encryption, which can generally be classified into spatial-domain and frequency-domain approaches. In this work, a hybrid encryption method based on singular value decomposition (SVD) and discrete wavelet transform (DWT) is developed within a conventional digital watermarking framework. Compared with traditional techniques, the proposed DWT–SVD approach demonstrates enhanced robustness. To further improve resistance against additive white Gaussian noise (AWGN) attacks, a denoising scheme based on the dual-tree complex wavelet transform (DT-CWT) is incorporated. The experimental results confirm that, when compared with conventional DWT-based denoising methods, the DT-CWT algorithm provides superior noise suppression performance. Specifically, the proposed approach achieves a mean squared error (MSE) of approximately 0.0041 and a peak signal-to-noise ratio (PSNR) of about 70.015 dB under Gaussian noise conditions, indicating strong robustness and high-quality image reconstruction.