An objective comparison between spatial and DCT watermarking schemes for MPEG video

Digital watermarking is an important emerging technique for intellectual property rights protection. We classify spread-spectrum watermarking techniques for MPEG video into two generic classes, namely spatial watermarking and DCT (discrete cosine transform) watermarking schemes, and evaluate their robustness and visual quality quantitatively and comparatively. Blind watermark detection and some watermark attacks are considered. For the two test video files considered in this study, it is observed that spatial watermarking may be preferred to DCT watermarking, as the latter tends to be less robust when both schemes are compared at the same visual quality level for the watermarked video