A Contourlet-Based Image Watermarking Resisting to JPEG Compression

A novel image authentication algorithm resisting to JPEG compression is proposed. The authentication water- mark is generated based on the stability of relationship of adjacent Contourlet transform coefficients before and after JPEG. According to the random block mapping, the watermark is embedded into the discrete cosine transform (DCT) co- efficients of other image blocks. The tampering identification matrix is determined by the difference between extracted watermark and reconstructed watermark, and adjacent region comparison is adopted to determine the authenticity of im- age blocks. Experimental results show that the algorithm can achieve blind detection with better resistance to JPEG com- pression, also able to position malicious tampering more accurately.