Digital watermarking for camera-captured images based on just noticeable distortion and Wiener filtering

In this paper, we propose a digital image watermarking method for camera-captured images. In our proposed method, an image component of all image pixels is used for embedding an individual watermark bit in order to provide large amount of the embedded watermark. The watermark strength is adjusted in accordance with the modified just noticeable distortion. After the watermarked image is printed and then captured by a digital camera, the reliable watermark extraction is accomplished based on the techniques of reducing distortions introduced from the printing and camera-capturing processes, and predicting original image component from the watermarked image component. In the experiments, various types of pixel value distortions and geometric distortions are considered and explored. With the proposed method, the results show that the watermark can be invisibly embedded, and reliably extracted. We also demonstrate its robustness against various types of distortions from the printing and camera-capturing processes.