Wavelet Tree Quantization for Copyright Protection Watermarking

TLDR

The authors propose a blind watermarking scheme based on wavelet‑tree quantization to protect copyright and demonstrate its robustness against various attacks. The scheme groups wavelet coefficients into super trees, quantizes them to embed watermark bits in perceptually important frequency bands, and spreads the mark across large spatial regions, creating a statistical difference for extraction. Experiments show the method provides greater robustness to time‑domain geometric attacks.

Abstract

This paper proposes a wavelet-tree-based blind watermarking scheme for copyright protection. The wavelet coefficients of the host image are grouped into so-called super trees. The watermark is embedded by quantizing super trees. The trees are so quantized that they exhibit a large enough statistical difference, which will later be used for watermark extraction. Each watermark bit is embedded in perceptually important frequency bands, which renders the mark more resistant to frequency based attacks. Also, the watermark is spread throughout large spatial regions. This yields more robustness against time domain geometric attacks. Examples of various attacks will be given to demonstrate the robustness of the proposed technique.