Research On Video Watermarking Algorithm Based On H.264/AVC

In recent years,the development of online video industry and more videos online makes video copyright protection and certification more urgent.With the high-definition video becoming larger and larger,videos are stored and conveyed after compression typically.As the latest standard compression coding,the efficiency of H.264/AVC has been greatly improved compared with conventional compression standard.Therefore,video watermarking algorithms based on H.264/AVC have good value.Combining the features of H.264/AVC codec and human visual system,two important branches of video watermarking based on H.264/AVC,non-reversible video watermarking and reversible video watermarking technology have been discussed.The main work and research results of this paper are as follows:(1)In order to solve the shortage of video watermarking ability to resist recompression attacks,this paper developed a non-reversible watermarking algorithm based on chrominance quantized residual coefficients of I frame.The proposed algorithm elaborately analyzes the intra-prediction mode,residual coefficients and coded block pattern of H.264/AVC codec.Chrominance component was selected to embedding watermarks.According to thought of differential energy,it embedded Arnold transformation scrambled watermarking information by slightly modulating one DCT residual coefficient of the two specific non-zero quantized DCT coefficients.Embedding watermarks in chrominance component could effectively solve the synchronous problem after recompression and improve the anti-recompression performance of watermarking algorithm.Compared with other existing algorithm,this algorithm itself does not need to record watermark embedding location,which further optimizes the concealment and security.(2)In order to solve the shortage of video watermarking imperceptibility and ability to tamper localization,this paper presents a novel reversible watermarking algorithm based on intra-prediction mode.The proposed algorithm generates signature by prediction mode in each I frame macro block.According to features of H.264/AVC codec,the minimum error coefficient in each luminance 4×4 residual block is selected by error-compensation method.Feature information is embedded in the selected coefficient as watermarks by difference expansion.The experimental results show the original video can be recovered with any distortion if the watermarked video was not tampered,otherwise the tampered region can be localized accurately,and the tamper localization accuracy is 4×4 blocks.Compared with previous H.264/AVC reversible watermarking schemes,the presented method not only achieves high embedding capacity and good imperceptibility,but also has more accuracy for tampering detection.Currently,H.264/AVC codec is prevailing video compression standard.Therefore,the video watermarking algorithm based on H.264/AVC is the focus of research on video watermarking.The non-reversible and reversible watermarking algorithm presented in this paper provides new thoughts for video copyright protection and content authentication,which has a certain practical value.