Research On Digital Video Watermarking Algorithm Based On H.264

Digital video watermarking is a powerful tool for video copyright protection and security authentication. By embedding the watermark into video, we can achieve the copyright protection, the integrality authentication, advertising monitoring and so on. H.264 is a new generation of video coding standard which has advantages of high-performance compression and wide application. So it is particularly suited for high-quality video services at low bit-rate. Therefore, the research of the watermarking algorithm for authentication video based on H.264 is great significance.The paper studies the existing video watermarking algorithms and analyses their defects. Considering the characteristic of video content authentication and H.264 coding standard, the paper improves the video feature extraction and embedding algorithm based on differential energy, then proposes a video content authentication watermarking algorithm based on H.264. The algorithm can detect and localize the tempered areas when it achieves the goal of video content authentication.Through the research of traits of the DCT coefficients of the intra frame coding based on H.264, a new algorithm of watermarking for low bit-rate video in compressed domain is addressed. The authentication code is created according to the relationship of the quantized DCT coefficients of the intra frame during the H.264 encoding progress. After that, the authentication information as watermark is embedded into the high frequency quantized DCT coefficients of the intra frame.Experimental results show that the two algorithms both keep small distortion and lower algorithm complexity and fairly meet the essentially technical requirement of video watermarking system, such as imperceptibility, blind extraction and real time property, which have a higher application value.