Extraction of multiresolution watermark images for resolving rightful ownership

Digital watermarking has been recently proposed as the mean for intellectual property right protection of multimedia data. We present some ways to "visualize" the invisible watermarks, both statistically and perceptually, for proving the ownership. A system which is capable of embedding a good resolution meaningful binary watermark image and later extracting different versions of that watermark image with varying resolutions is proposed. The system has the nice feature that the watermark detector (rather than encoder) is allowed to adaptively choose the trade-off between robustness degree and resolution of the extracted watermark image. It takes advantage of the high spatial correlation of the watermark image and the human visual system's super ability to recognize a correlated pattern to enhance the detection performance. While a statistical technique which can quantify the false alarm detection probability should be considered as a fundamental measure for a valid ownership claim, the ability to extract a meaningful watermark image will greatly facilitate the process of convincing the jury of an ownership claim.