Highly Effective Digital Watermarking with Wavelet Transform and SVD Algorithm

This source code implements a digital watermarking algorithm based on wavelet transform combined with singular value decomposition (SVD). The implementation specifically selects the LH (Low-High frequency) subband of carrier images for watermark embedding, which provides optimal balance between visibility and robustness. The algorithm has undergone comprehensive attack testing including noise addition, compression, and filtering attacks, demonstrating excellent performance in preserving watermark integrity. This watermarking technique holds significant importance for protecting image copyright and authentication information, effectively preventing unauthorized copying and tampering. The core algorithm workflow involves: 1) Applying discrete wavelet transform (DWT) to decompose the host image 2) Extracting the LH subband for SVD processing 3) Embedding watermark data into singular values 4) Reconstructing the watermarked image through inverse transformations. Through code optimization and algorithmic improvements, the performance and robustness can be further enhanced, making it suitable for broader application scenarios such as medical imaging security, digital rights management, and forensic authentication. The modular code structure allows for easy customization of embedding strength and adaptive thresholding parameters.