Research Of MPEG-4 Video Watermarking Technologies

With the rapid development of computer network, Multimedia knowledge copyright protection becomes all urgent problem to be solved. Copyright protections of digital watermarking technology are getting attention as an important means. Digital watermarking technology is divided into image watermarking, video watermarking, etc., video watermarking as an important branch becomes a hot topic.This paper introduces the concept of video watermarking, the main features, classification and technical difficulties, then analyzes the MPEG-4 video compression standard principle and research the typical MPEG-4 video watermarking algorithm. An accurately and blind watermarking algorithm based on MPEG-4 video was proposed. The original bit sequence is coded by using RS error-correcting, then periodic embedded into the AC coefficients of the quantized DCT coefficients of video, and then encode the watermark to generate the MPEG-4 video. When extracting the watermark, decode the containing video to get the quantized DCT coefficients, get the watermark by using LSB, and RS decoded to get the same sequence as the embedded bit sequence.The proposed algorithm is simple and efficient. Moreover, watermark can be extracted blindly without original images. Compared with the original video sequences before watermark, PSNR of watermarked frames is reduced slightly. The experiment results demonstrate that this method can accurately extract the bit sequence, while the video watermark is invisible, real-time, and this method has good robustness for frame deletion, insertion and noise frame attack.