CAJ | 학술논문

提出了一种基于分块Hadamard变换的鲁棒图像水印算法.水印图像先进行置乱和扩展得到水印序列.原始图像进行8×8分块的Hadamard变换,在中频系数里按不同强度嵌入水印.水印提取时,先计算与原始图像在对应的变换域系数的差值,再计算该差值与水印编码的相关性来确定每个水印像素.实验表明,该算法对原始图像的视觉影响小,具有良好的鲁棒性.
제출료일충기우분괴Hadamard변환적로봉도상수인산법.수인도상선진행치란화확전득도수인서렬.원시도상진행8×8분괴적Hadamard변환,재중빈계수리안불동강도감입수인.수인제취시,선계산여원시도상재대응적변환역계수적차치,재계산해차치여수인편마적상관성래학정매개수인상소.실험표명,해산법대원시도상적시각영향소,구유량호적로봉성.
This paper proposes a new robust watermarking algorithm based on block Hadamard Transform(HT).The binary watermark image is displaced to destroy space relativity and then expanded to get watermark sequence.The original image is subdivided to 8×8 blocks and is executed HT transform.Then middle HT coefficients are selected to hide watermark.The correlation of watermark code and the difference of HT coefficients between embedded and original image is used to determine each bit when watermark is detected.Experiment shows that the algorithm has no appreciable influence to image appearance and it is robust to JPEG compression,clipping,filtering and noise pollution.