Progresses of color image watermark methods

Due to the advent of network and computer technology, there has been an explosion in the use of digital media through electronic commerce and on-line services. The increasing importance of watermarking technologies is proved by the need of very efficient methods in data security including copyright protection, data integrity detection. Existing digital watermarking algorithms are mostly designed for gray images but many are not for color images. This paper presents some color image watermark methods proposed in recent years so as to give help for researchers to study deeply.