Digital Watermarking Program with DWT-SVD and Chaotic Encryption

In this document, I present a digital watermarking program developed in MATLAB. The implementation utilizes the Discrete Wavelet Transform (DWT) method, which decomposes the input signal into four distinct sub-bands (LL, LH, HL, HH) through multi-resolution analysis. The program specifically targets the LL sub-band for watermark embedding due to its energy concentration properties that ensure better robustness. The algorithm integrates Singular Value Decomposition (SVD) with DWT by applying SVD to the LL sub-band coefficients, allowing watermark insertion in the singular values matrix for enhanced stability against attacks. For security measures, chaotic encryption is implemented using logistic maps or similar chaotic systems to encrypt the watermark data before embedding, providing additional protection against unauthorized extraction. This package includes two complementary versions: a GUI-based application (dwt_svd_GUI.rar) for user-friendly interaction and visualization, and a standard M-file version for direct code execution and customization. The core implementation involves key MATLAB functions including wavedec2 for 2D wavelet decomposition, svd for matrix factorization, and custom chaotic sequence generation for encryption.