Wavelet Transform-Based Digital Watermarking with Code Implementation

This article presents wavelet transform-based digital watermarking technology with comprehensive code explanations and experimental results. Digital watermarking via wavelet transform serves as a covert and efficient information hiding method that embeds specific watermark data into media such as images or audio files to ensure data security and uniqueness. The code implementation section elaborates on the algorithmic workflow, including key functions like wavelet decomposition (using functions such as wavedec2 for 2D signals), watermark embedding in selected frequency subbands (typically HL, LH, or HH bands), and inverse wavelet reconstruction (waverec2). The experimental results section demonstrates practical applications of this technique, evaluating performance metrics including Peak Signal-to-Noise Ratio (PSNR) for transparency assessment and robustness tests against common attacks like compression and filtering. Through this article, readers will gain deep insights into wavelet-based digital watermarking technology and master its practical implementation and performance evaluation methodologies.