A Compressed Video Watermarking Scheme with Temporal Synchronization

As an effective technology for copyright protection, digital watermarking has been applied in videos. Temporal synchronization is an important aspect for video watermarking. If synchronization is lost, the detector may fail in extracting the correct watermark. This paper proposes a temporal synchronous compressed MPEG-4 video watermarking scheme. This scheme utilizes DCT direct current coefficients to divide video into several scenes. Watermarks are embedded according to features of scenes. Bit rate control is introduced to ensure that watermark embedding does not increase the size of video. Drift compensation is employed to counteract the visual distortion in P-frames and B-frames caused by watermark embedding. Visual masking is exploited to enhance the invisibility of watermark. Experimental results show that the scheme has satisfactory ability in resisting the temporal synchronization attacks of frame deleting and frame inserting, therefore achieving well robustness.