Grayscale Digital Watermark Embedding Algorithm Based on Wavelet Transform

I would like to share a grayscale digital watermark embedding algorithm based on wavelet transform. This implementation uses MATLAB for the core watermarking process, which typically involves discrete wavelet transform (DWT) decomposition of host images, strategic modification of wavelet coefficients in selected subbands (like HL/LH frequencies), and inverse DWT reconstruction. The algorithm employs coefficient quantization or additive embedding methods for watermark insertion while maintaining visual quality. The original research paper detailing the mathematical framework is included for reference. While the current implementation provides a working foundation, I believe there are opportunities for enhancement in areas such as adaptive thresholding, robustness testing against attacks, and optimization of embedding parameters. For researchers interested in digital watermarking techniques, this implementation offers valuable insights into wavelet-based approaches and practical MATLAB coding patterns for frequency-domain watermark embedding.