SVD-DCT Image Watermarking Implementation

This MATLAB code implements SVD-DCT image watermarking, a technique for embedding hidden information within digital images. The implementation utilizes Singular Value Decomposition (SVD) and Discrete Cosine Transform (DCT) to embed watermarks in the frequency domain of host images. The core algorithm involves preprocessing the image using DCT transformation followed by SVD decomposition of the transformed coefficients. The watermark is embedded by modifying the singular values obtained from the SVD process. Key MATLAB functions employed include dct2() for 2D DCT transformation, svd() for matrix decomposition, and idct2() for inverse transformation during watermark extraction. This technology serves multiple purposes including copyright protection, image authentication, and security enhancement. The code provides a complete workflow from watermark embedding to extraction verification. The embedding process maintains visual quality while ensuring robust watermark detection through inverse transformation procedures. This implementation serves as a foundational example that can be modified and extended based on specific requirements. Potential enhancements could include optimizing embedding strength parameters, implementing adaptive thresholding for better robustness, or adding support for various image formats and watermark types. The modular structure allows for easy integration of additional features such as noise resistance testing or compression robustness evaluation.