A Video Watermarking Algorithm Research Based On HEVC

With the rapidly development of information and network technology,digital video product has penetrated into people's daily life.Unfortunately,the copyright problem has emerged when the digital video products are enjoyed by human.However,this problem can be dealt with effectively by embedding watermark in digital video.High efficiency video coding(HEVC)has been studied and formally proposed in June 2013,for which the algorithm based on H.264/AVC cannot adapt to the increasing of coding complexity.In addition,the robust video watermarking algorithm can play a good role in copyright protection.At the same time,the reversible watermarking algorithm may damage the host information,that is to say,video with watermark may not completely restore the original data and lead to serious consequences especially in the case of more sensitive distortion such as military,medical,and satellite.Thus,a reversible watermarking algorithm based on HEVC is emerged and become a host spot for research.For this,a robust video watermarking algorithm for HEVC based on intra-frame prediction modes of multi-partitionly and a reversible watermarking algorithm for HEVC intra-frames without error propagation have been proposed in this paper.1.Considering low robustness and intra error propagation problems of existing video watermarking algorithms for HEVC,a robust video watermarking algorithm for HEVC based on intra-frame prediction modes of multi-partitionly has been proposed.Firstly,in order to eliminate the intra-frame error propagation after embedding watermark,embeddable regions were selected and the texture direction was calculated for 4×4 luminance blocks.Secondly,a scheme was proposed that the 33 angular prediction modes were divided into four pattern sets,which were recorded as follows: upper horizontal,lower horizontal,upper vertical,lower vertical.Finally,the four pattern sets were mapped to the values of the current and next to be embedded watermarks.Once the current 4×4 luminance blocks met the pattern sets,the current 33 angular prediction modes were truncated into the current pattern sets and the watermark was embedded.The watermark was extracted by the texture direction and four prediction pattern sets at decoding side.The experimental results show that,the average Peak Signal to Noise Ratio(PSNR)of the proposed algorithm is almost unchanged.Therefore,the proposed algorithm has low video distortion and can well resist the re-encoded attacks in robustness.2.On the basic of analysis the uniqueness of HEVC,a reversible watermarking algorithm which combine error propagation elimination with low bit rate growth is proposed.We first propose two models to eliminate the error propagation causes by embedding watermark.At the same time,the effect of 4×4TU after embedding watermark for transform and quantization coding procedure is demonstrated.Then we analyze the residual coefficients which are perturbed in 4×4TU blocks with low bit rate growth in conformity with the context adaptive binary arithmetic coding(CABAC).Finally,to achieve the reversible watermarking algorithm,the upward parity modulation(TUPM)and the shift least significant bit(SLSB)are considered in the procedure which the watermark is embedded in 4×4TU blocks by three types of scans.The experimental results show that,the proposed algorithm has low bit rate growth.In addition,the proposed algorithm achieves double capacity without error propagation for the intra constructed blocks.Moreover,the original video date can be completely restored without any distortion if the decoder contains the watermark extraction and restore module.