Abstract
Recently, multimedia data such as still images, motion images and audio signals have been widely used. However, they can be simply and frequently duplicated without degradation, so that many copy problems may be caused. To solve this problem, copyright information as a signature and ID is embedded into an image. When images are used by unexpected some one without authentication, it is possible to protect copyright by extracting an embedded data from an image and verifying them. Such methods are called watermaiking methods. In this paper, we propose a watermaking method, where we use Discrete Cosine Transform(DCT)as orthogonal transform. Our proposed method is to embed data with considering embedded image quality and robustness to attack. Especially, the proposed scheme has much robustness for JPEG compression. Finally, we show simulation results for our proposed scheme.
