Research On Video Watermarking

With the rapid progress of computing speed, storage capacity, internet and information technology, applications of text, images, video, audio and other digital products are increasingly rich. The advantages of digital product include perfect copying and easier and more efficient transmission over information network, make us convenient, but increase demand of information security protection and multimedia authentication technologies. Nowadays, the copyright protection is in great demand, especially in the case of pay-TV, confidential video conferencing, VOD (video on demand), confidential facsimile, DVD (Digital Video Disk), HDTV (High Definition Television), medical applications, as well as various defense applications.In this paper, the date structure and code of the MPEG-4 verification model and applications of video watermarking based on MPEG are studied. The foundation of video watermarking is discussed, including classifying, advantages, application, research status, challenge, development trend, etc. Several algorithms of MPEG-4 watermarking are studied. This paper presents a method in which the watermark is inserted by imposing particular relationships between corresponding middle frequency DCT coefficients. The method integrated with MPEG-4 verification model coder, has not effect on quality of video and efficiency of encoder and decoder. The method based on VO has following advantages: (1)Embedding and recovering are very simple and can be applied in real-time situation. (2)The computational cost of the time of embedding and recovering are small. (3)The method can endure severe attacks such as frame skipping, frame cutting.Encryption is one of the most important means for information security and copyright protection. The digital media will be scrambled before it is distributed. Only authorized users who have the proper key for decryption can access the clear content. Based on the thinking of scrambling and watermarking are complementary to each other, a novel video scrambling algorithm is given in this paper. The algorithm has following advantages: (1) Encoding and decoding are very simple and they can be applied in real-time situations. (2) The algorithm can endure severe attacks such as extreme noise levels, very high loss in its data or data packets. (3) The algorithm is independent on any video format or encode mode.