Hybrid Algorithm for Watermarks in Digital Color Images Using DCT-DWT
Keywords:
Digital image watermarking, Discrete Cosine Transform, Discrete Wavelet Transform, RGB (Red-Green-Blue Color Format, AttacksAbstract
During the fast development of the information technologies, the Watermarking technique eventually became a very useful mechanism for copyrights protection for multimedia producers.
Robustness and imperceptibility at watermarked image, are considered as two important facts in the digital watermarking.
In this research, a hybrid algorithm watermark in the digital images is proposed according to Discrete Wavelet Transformation and Discrete Cosine Transformation. first, we convert the host color image to the three RGB layers that makes up the image then we choose the layer that we want to apply the watermark on and divide it into 8 blocks and add the Discrete Cosine Transformation watermark then the Discrete Wavelet Transformation is applied to choose the LH matrix resulting from the Discrete Wavelet Transformation where the watermark is included.
The watermark is included in a way that allows us to control the strength of the embedding algorithm, making it more applicable to adapt according to the desired application, and this is what distinguishes this algorithm from another, and then we reverse the previous transformations and combine the three image layers, the experimental results show that the imperceptibility of the algorithm is high quality, and it has effective robustness against common attacks of watermarks
