Research On The Algorithm Of Invisibility And Robustness Of Watermark Based On Coding Video Carrier

With the rapid development of computer,multimedia information has been popularized and various types of multimedia files have been widely spread.How to ensure that the information can be safely transmitted in the multimedia carrier in the environment of highspeed development of multimedia information has became a hot research topic in the field of information security.This disseration designs two watermarking algorithms based on H.264 and HEVC encoded video.Through the simulation experiment,the robustness and invisibility of the watermark algorithm are improved.The work of this dissertation can be summarized as the following two algorithms:(1)A robust video watermarking algorithm based on H.264 video frame coefficient energy allocation is studied.Aiming at rate distortion of the video during the H.264 encoding process,the bit rate of the H.264 encoded video will be controlled to improve the visual quality of the video.By the video watermarking algorithm of video frame coefficient energy distribution,the discrete cosine coefficients in the macro block of the video frame are allocated,the coefficient block that meets the embedding rules is selected as the embedding position of the watermark,and finally the preprocessed watermark information is embedded in H.264 encoded video carrier.Compared with some existing algorithms,dividing the effective block and the invalid block for the embedding position of watermark.The robustness and invisibility of watermark are improved with the partition of effective block and invalid block.Its robustness and embedding capacity are effectively improved with the increase of accuracy.Simulation experiment results show that the viewing quality of H.264 encoded video has been effectively improved,and the robustness and invisibility of the watermarking algorithm have been improved.(2)A robust video watermarking algorithm based on HEVC video frame redundancy information separation is studied.The code rate control of HEVC encoding is optimized,so that the code rate of the encoded video is effectively controlled.Through the watermarking algorithm of the redundant information separation of the HEVC video frame,the front view and the rear view of the HEVC encoded video frame are separated.According to the characteristics of the front view and the back view,the back view is selected as the embedded frame of the watermark,and finally the pre-processed watermark information is embedded into the HEVC video carrier.Compared with the existing robust watermarking algorithms for partial HEVC encoded video,the watermarking algorithm in this dissertation has improved in the embedding area of the watermark.It is no longer a single video frame embedding,but a video frame that is more suitable for watermark embedding rear view.The results of simulation experiments show that the viewing quality of HEVC encoded video is improved,the PSNR value of the video carrier and the NCC value of the watermark are effectively improved,and the robustness of the watermarking algorithm in this dissertation is improved.In conclusion,the two watermarking algorithms proposed in this dissertation improve the robustness and invisibility effectively,and also improve the problem that the bit rate of video increases too fast because of embedding digital watermarking.