A novel image fragile watermarking algorithm based on chaotic map

By using of chaotic map and block-wise independent technology, a new chaotic fragile watermarking algorithm is proposed in this paper. Firstly, location key is looked as logistic chaotic initial value to iterate and create location matrix, according to this matrix we can generate mapping image and identify the embedding location of watermarking in image blocks. Then watermarking sequence related with mapping image blocks and generated by he non chaotic map is embedded into the LSB of corresponding location in the block so as to achieve the different watermarking sequence even if image blocks is same, and effectively overcome security flaws of the block-wise independent watermarking algorithm. In addition, since the image content and watermarking were staggered, the algorithm had a higher security, and we needn't the original image when extracting watermarking. The accuracy of tamper localization can be achieved 2 x 2 block pixels. We provide experimental results to demonstrate the effectiveness of our method.