In Due to increasing use of computer networks and Internet, digital contents can nowadays be easily exchanged. As a result many copyrighted contents may be shared illegally and this has concerned multimedia owners. In order to overcome this problem, watermarking schemes have been proposed to protect copyright of digital contents such as digital images, in spatial and transform domains. Transform domain methods have attracted more attention because they are more robust against possible attacks. Robustness and visual quality are two conflicting features that should be attained at the same time in a proper watermarking scheme. Obtaining these features require high computational complexity, which makes it inappropriate for use in many real-time watermarking applications. Therefore, improving the computational complexity of complicated watermarking techniques by decreasing execution time has become a challenge. In this thesis, after presenting watermarking concepts and applications, based on characteristics of watermarking and potential of parallelism, watermarking schemes in spatial and transform domains are reviewed and justify; LINE-HEIGHT: normal; TEXT-INDENT: 18pt; MARGIN: 0cm 0cm 0pt" Keywords: Watermark, adaptive watermarking, robustness, Imperceptibility, GPU, parallelism
