Research On Video Vontent Authentication Technique Based On H.264

In recent years, with the continuous development of network technology and multimedia technology, coupled with the popularity of mobile phone and high-definition digital television equipment, information exchange is growing at an unprecedented depth and breadth, and has become an indispensable part of people’s lives. With the exchange of information in a time of rapid development, various kinds of information for the authenticity of the software also bring challenges. Digital watermarking technology is the most effective method for the protection of information by far.Currently, transmitting large-scale digital information is a big challenge for the network bandwidth, so we generally achieve this by transmitting the compressed video. During the process of watermark video coding, we often can not extract or test it effectively. Therefore watermarking technology based on video codec standard is of great significance. H.264/AVC coding standard has a better network adaptability and superior data compression capabilities, and is the international mainstream video compression standard. Therefore, the study based on H.264/AVC video codec standard has a deep significance for watermark technology.As digital video technology has become more and more popular, the video has become an important medium for information recording and forensics, legality certification of its content has become a hot issue to be solved. Legality certification issues usually include two aspects. On the one hand, the identity of the owner of the video must be verified that the video is from the legal owner; on the other hand, as an information carrier, the content of the video must have legitimacy, which means that semantic information within the video is true and correct, without any modification semantics. Currently the standard for video encoding and decoding video watermarking technology is not mature enough, facing some of the deficiencies of the current video watermarking algorithm, this paper made a preliminary exploration of video watermarking algorithm, combined codec standard features as well as the human visual characteristics HVS (Human Visual System), focusing on the fragile watermarking and semi-fragile watermark for video content authentication. The main contents and innovations are as follows:The main contents and innovations are as follows:(1) This text is based on the H.264 standard code,embing the DCT domain watermark in texture region in P frame, making the discrimination of characteristics of residual block through texture templates preset, and selecting watermark embedding location adaptively;selecting the Motion Vector domain watermark in non-texture regions in P frame,and embed the watermark into the larger of the motion vector direction when the motion vector size is greater than the threshold.(2) In this paper,we combine H.264 coding standard with characteristics of video content, catch the I frame into 8×8 block and get DC coefficients of each block. Then we judge the correlation of the DC coefficient between the blocks using the predefined matrix, and get a value of two sequences.Finally we embed the watermark by modifying the last nonzero coefficient on those blocks which are not in the low frequency region.