Research Of Steganography Algorithm Based On Motion Vectors Of H.264

In recent years, along with the rapid development of Internet technology anddigital multimedia technology, the illegal use tempered and transferred has been moreand more serious. Information hiding, as one of the most importment way of solvingthis problem, has grown up fast since the20thcentury. On one hand, it helps toprevent digital information from being tempered forged pirated and attacked. On theother hand, it can be regarded as such channel of transferring specific information. Inresearch and application of multimedia, the situation in which digital video is treatedas the host has been very extensive.H.264is the new gererition of video compression coding standard. It hasexcellent compression performance and video quality, so it is widely used in networkvideo high definition digital TV video real-time communication and other aspects.Byanalysing the characteristics of H.264video coding standard and motion vectors, asteganography algorithm based on motion vectors of H.264is proposed in this paper.The algorithm introduces the diamond coding to achieve information hiding by aslight modulation of motion vectors. Not only can the diamond coding effectivelyreduce the modification rate of motion vectors, but also it can improve the embeddingcapacity. In the embedding process in order to reduce the effects on the bit rate andvideo image quality caused by information embedding, regions with complex texturesand larger motion vectors are selected as the embedded points.The algorithm realizes the blind extraction of information. During the extractionprocess, it only needs to decode the motion vectors of macroblocks. Through thethreshold, the extraction algorithm can get secret information easily. In the extractingthe process it does not require a lot of calculations.Its extracting method is simple andrapid.Experimental results show that the algorithm ensures good video quality andlarge embedding capacity and it has little effects on the bit rate.