Novel Hybrid Blind Digital Image Watermarking in Cepstrum and DCT Domain

The problem of affine transform attacks refers to many watermarking algorithms. A slight change in the geometry of watermarked image can disable the decoding of embedded information; therefore the advanced watermarking methods should be robust against the above-mentioned procedures. This paper contains a description of the algorithm consisting of two complementary methods of image watermarking. The watermark is encoded in the luminance and chrominance components in the spatial and frequency domains. The decoding process takes place in the two-dimensional Cepstrum and the discrete cosine transform. The algorithm makes the watermarked image robust against the following affine attacks: scaling shearing and translation. Also the following image distortion processes like JPEG lossy compression, adding noise to the watermarked image, median filtering and majority cropping do not cause any loss of hidden information.