Digital Image Watermark Embedding and Extraction

This MATLAB-based implementation demonstrates digital image watermark embedding and extraction using wavelet transform methodology. The program employs discrete wavelet transform (DWT) for frequency domain processing and implements blind detection without requiring the original host image. This implementation is particularly valuable for researchers working in digital watermarking research. The watermarking technique provides copyright protection for images while ensuring authentication and data integrity verification. It finds extensive applications in digital media domains including image authentication, information hiding, and data tracking. The program structure includes key functions for: DWT decomposition using wavelet filters, watermark embedding through coefficient modulation in selected subbands, and extraction via inverse transformation with threshold-based detection. The user-friendly implementation follows clear operational procedures, enabling researchers to comprehensively understand and apply digital watermarking technology. The code demonstrates practical aspects of embedding strength adjustment, robustness testing, and performance evaluation metrics suitable for academic research and algorithm development.