This paper presents a copyright owner detection technique for images and graphics. A digital time-stamped signature for this copyright identification technique is also introduced in this work. The secret key, used to compute the watermark, is generated from the extracted features of the host images in the proposed scheme. The proposed algorithm enables the successful revealing of watermarks under several attacks, such as filtering, lossy compression, cropping, rotating, and so on. In particular, our method is not only suitable for ordinary natural images, but can also be applied to cartoon graphics. Most importantly, the proposed scheme can be applied to the media in which distortion is not allowable, such as medical images, source code of programs, and so on.
