摘要：Digital image watermarking is a copyright protection technology aimed at asserting intellectual property rights of digital images by inserting a copyright identifier in the contents of the image, without sacrificing its quality. In this paper, we propose an imperceptible and a robust digital image watermarking algorithm for the colour images. The proposed algorithm is a hybrid algorithm based on combining two powerful transform domain techniques; the Discrete Wavelet Transform (DWT) and the Discrete Cosine Transform (DCT). The proposed algorithm deals with the extraction of the watermark information in the absence of original image, hence the blind scheme was obtained. Performance evaluation results demonstrate the effectiveness of the proposed algorithm with respect to the conflicting requirements of image watermarking; imperceptibility and robustness against common image processing operations
