A Discrete Wavelet Transform Based Robust Watermarking for Copyright Protection

Digital watermarking is a simple and effective way to provide copyright protection. This paper proposes a robust and blind watermarking scheme for static images. It utilizes discrete wavelet transform and applies three coding methods according to the different characteristics of band coefficients: lattice code based on the communication principle, modification of insignificant coefficients based on the just-noticeable distortion of the human visual model, and quantization index modulation based on singular value decomposition. Together, these methods embed a watermark while maintaining image fidelity. The experimental results prove that the proposed method is robust against frequency-based and time domain geometric attacks. Key-Words: Digital watermark, Discrete wavelet transform, Copyright protection, Watermark Extraction Procedure, Watermark Verification.