Design of Image Watermarking Algorithm Resistant to Copy Attack

Combined with one-way hash function, the parity of block DCT coefficients and JPEG quantization technology, etc., this paper proposes a new algorithm: image watermarking algorithm resistant to copy attack. This algorithm uses PN sequence encryption to ensure the security of watermark and blind extraction when recovering watermark, some common attack experiments of image processing verify the performance of watermark generated through this algorithm. Compared with those algorithms which need to use original images to recover data, this algorithm is more practical and it has very good robustness and transparency.