Adaptive Reversible Image Watermarking Method Based on Integer Transform

To ensure the quality of watermarked image and improve the embedding capacity of watermarkings, an adaptive image reversible watermarking method based on interger transform is proposed in this paper, which defines a new generalized integer transform algorithm. Through the use of the method the image blocks of arbitrary sized are transformed, producing certain redundancy data that can be used for watermarking embedding. In addition, the parameter m used for integer transform is adaptively selected according to the variance of every image block, hence allowing for embedding more data bits into the smooth blocks while avoiding large distortion generated by complex ones, and thus the algorithm ensures a higher embedding capacity and better quality of watermarked image. Compared with similar algorithms, the experimental results show that the proposed method has larger maximal embedding capacity and taking Lena as a host image, the real payload can reach up to 2.36 bpp. The proposed integer transform algorithm is simple; through adaptively interger transforming and data embedding, the quality of watermarked image can be assured and the method offers a large real payload.