Color image watermark technology base on human visual detection characteristics

Combined with contrast sensitivity characteristics of human vision system and image feature in transform domain,a new method is proposed for calculating the human perception error threshold of image.Combining the calculated threshold,a new color image watermarking scheme is brought forward,and the attack test and simulation experiments are carried out.The results show that,watermark information extracted from attacked images embedded watermark is still visible,the normalized coefficient values after compression attack with the compression quality factor 50% still can reach more than 0.7371,which shows that watermarking scheme proposed has good transparency and high robust.And in the watermark embedding and extraction process,the original color image is transform into the device-independent CIELAB color space in order to improve the robustness of the watermark.Synthesis results show that the proposed watermarking scheme is an effective watermark embedding and extraction scheme.