An adaptive wavelet-tree watermarking method and its implementation in mobile devices

Watermarking is a technique used for copyright protection. In this study, an adaptive wavelet-tree watermarking method is presented. The method is based on the authors´ previous work but has two major modifications. One is an adaptive adjustment of wavelet-tree coefficients that improve image quality. The other is an adaptive watermark extraction used for a variety of images. Experimental results showed that the proposed method not only can decrease computation, it also can increase the robustness of watermarks under common attacks, such as Gaussian filtering, average filtering, median filtering and JPEG compression. Moreover, the proposed method is successfully implemented on the Android OS for potential applications in mobile devices.