Semi-Blind RGB Color Image Watermarking Using DCT and Two Level SVD
Bokan Omar Ali, Ghazali Sulong · Signal & Image Processing An International Journal · 2013
This paper presents semi blind RGB color image watermarking using DCT and two-level SVD.First, RGB image is divided into red, green, and blue channels.The blue component is divided into blocks according to the watermark size.Second, DCT is applied to each block to form a new block in the transform domain.DC component is retrieved and assembled from each block to form a new matrix of 128x128 pixels.SVD is applied to the resultant matrix to obtain matrices, U, S and V.The watermark is embedded into the S matrix.The watermark can be extracted without original host image, however, matrices U1, S and V1 are required.Experimental results indicate that the proposed algorithm can satisfy imperceptibility and it is more robust against common types of attacks such as filtering, adding noise, geometric and compression attacks.