A robust oblivious watermarking technique

Digital watermarking is an effective and popular technique to disapprove illegal copying and distribution of copyrighted digital content. One of the important issues of watermarking is the robustness subject to resist the lossy compression of the watermarked image. In addition, in JPEG quantification, there is a question which is that the two similar DCT coefficients will be quantified to the same rank. It will cause the mistake of the extracting watermark from the lossy compression of the watermarked image. In this paper, a robust oblivious watermarking technique is proposed. This presented scheme performed in the middle frequency region of the original host image. The modification of the mid-frequency coefficients is corresponding to the quantization table in JPEG standard. And, the permutation operation is adopted in the block of the host image in order to discourage the effect of the JPEG quantification as discuss above. With this technique, the watermark can survive when the watermarked image is compressed using JPEG. Moreover, the proposed scheme doesn´t require the information of the watermark and the original host image in the extracting process.