A Novel Blind Image Watermarking Scheme Based on Support Vector Machine in DCT Domain

This paper proposed a novel blind image watermark scheme in discrete cosine transform (DCT) domain. The original image is divided into small image blocks with size 8*8 first, and then the binary watermark bits are embedded into DCT domain of image blocks adaptively through a novel watermark embedding algorithm. The original image is not needed in the extraction algorithm. For gaining good fidelity and robustness, support vector machine (SVM) is adopted to simulate human visual system (HVS) and class image blocks into several types. Different embedding strengths are determined for different image types as human has different sensitivity to them. There characteristics of image blocks are used for classification. The embedding locations are selected randomly ranging from 10 to 24 of AC coefficients by a key to enhance the security of watermark. The experimental results show that our scheme has both good fidelity and strong robustness.