Color in image watermarking
Résumé
This chapter summarizes the state-of-the-art color techniques used in the emerging field of image watermarking. It is now well understood that a color approach is required when it comes to deal with security, steganography and watermarking applications of multimedia contents. Indeed, consumers and business expectations are focused on the protection of their contents, which are here color images and videos. In the past few years, several gray-level image watermarking schemes have been proposed but their application to color image is often inadequate since they usually work with the luminance or with individual color channel. Unfortunately, color cannot be considered as a simple RGB decomposition and all of its intrinsic information must be integrated in the watermarking process. Therefore, it is the chapter objective to present, first, the major difficulties associated with the treatment of color images, and second, the state-of-the-art methods used in the field of color image watermarking.