Watermarking technique based on wavelet transform for color images

Watermarking techniques have been proposed as an effective method to protecting the copyright of multimedia data. At present, a large proportion of the watermarking algorithms embed the grey image into the carrier image. In this paper, a watermarking algorithm for color images based on wavelet analysis is proposed. The algorithm scrambled the original watermark image in pretreatment, and used the wavelet transform to process the carrier image and the scrambled watermark image. Then the color watermarked image was embedded into the low-frequency discrete wavelet coefficient of the color carrier image. The experimental results demonstrate that the algorithm can assure the security of the watermark image, and the watermark image has good invisibility and strong robustness for common signal processing and attack.