A novel lossy-to-lossless watermarking scheme for JPEG2000 images

In this paper, we propose a lossy-to-lossless watermarking scheme for JPEG2000/J2K images. The watermarking is incorporated into the procedure of J2K coding in a way that the final watermark coded J2K bitstream can still maintain lossless-to-lossy scalability. To recover the original image, the J2K decoder does not need to extract the embedded watermark. This is achieved by dividing the magnitude bits of the wavelet coefficients into two portions, controlled by the watermarking survival rate (WSR). The upper portion is used to embed watermarks, while the lower portion is modified to compensate for the distortion introduced by the watermarks in the upper portion. Watermark detection can be done either from the upper portion or from the lower portion, based on a presetting threshold. Experimental results show that the J2K coded watermarked images still nearly follow the rate-distortion curve optimized for their original J2K images.