Current Issue : January - March Volume : 2018 Issue Number : 1 Articles : 5 Articles
compressed video bitstream can be partitioned according to the coding priority of the\ndata, allowing prioritized wireless communication or selective dropping in a congested channel.\nKnown as data partitioning in the H.264/Advanced Video Coding (AVC) codec, this paper introduces\na further sub-partition of one of the H.264/AVC codec�s three data-partitions. Results show a 5 dB\nimprovement in Peak Signal-to-Noise Ratio (PSNR) through this innovation. In particular, the data\npartition containing intra-coded residuals is sub-divided into data from: those macroblocks (MBs)\nnaturally intra-coded, and those MBs forcibly inserted for non-periodic intra-refresh. Interactive\nuser-to-user video streaming can benefit, as then HTTP adaptive streaming is inappropriate and the\nHigh Efficiency Video Coding (HEVC) codec is too energy demanding....
Detection of double video compression is of particular importance in video forensics, as it reveals partly\nthe video processing history. In this paper, a double compression method is proposed for HEVCââ?¬â??the latest video\ncoding standard. Firstly, four 5Ã?â??5 co-occurrence matrixes were derived from DCT coefficients along four directions\nrespectively, i.e., horizontal, vertical, main diagonal and minor diagonal. Then four 4Ã?â??4 co-occurrence matrixes were\nderived from PU types which are innovative features of HEVC and rarely been utilized by researchers. Finally, these\ntwo feature set are combined and sent to support vector machine (SVM) to detect re-compressed videos. In order to\nreduce the feature dimension, only the co-occurrence matrixes of DCT coefficients and PU types in horizontal\ndirection are adopted to identify whether the video has undergone double compression. Experimental results show the\neffectiveness and the robustness against frame deletion of the proposed scheme....
Multicast services grow up quickly and thus they urgently call for a secure mechanism to provide the\nconfidentiality and privacy of communications. Recently, multicast issues in Proxy Mobile IPv6 (PMIPv6) networks have\ngenerated a great deal of interest among researchers, and several multicast schemes had been proposed. However, these\nschemes do not take security issues into account. In an attempt to fill that research gap, we propose a dual multicast key\nmanagement scheme for secure group communications in PMIPv6-based Long Term Evolution (LTE) networks. This scheme\nsatisfies the requirements for forward and backward secrecy. Moreover, the performance analysis demonstrates that the\nproposed scheme incurs low communication and storage costs. Finally, we provide guidelines for Internet service providers\n(ISPs) to select the suitable multicast key management architecture....
Computer 3D character animation essentially is a product, which is combined with computer graphics and robotics, physics,\nmathematics, and the arts. It is based on computer hardware and graphics algorithms and related sciences rapidly developed new\ntechnologies. At present, the mainstream character animation technology is based on the artificial production of key technologies\nand capture frames based on the motion capture device technology. 3D character animation is widely used not only in the\nproduction of film, animation, and other commercial areas but also in virtual reality, computer-aided education, flight simulation,\nengineering simulation, military simulation, and other fields. In this paper, we try to study physics based character animation to\nsolve these problems such as poor real-time interaction that appears in the character, low utilization rate, and complex production.\nThe paper deeply studied the kinematics, dynamics technology, and production technology based on the motion data. At the same\ntime, it analyzed ODE, PhysX, Bullet, and other variety of mainstream physics engines and studied OBB hierarchy bounding box\ntree, AABB hierarchical tree, and other collision detection algorithms. Finally, character animation based on ODE is implemented,\nwhich is simulation of the motion and collision process of a tricycle....
A electric power group enterprises to actively explore the innovation of enterprise culture management,\nmaking full use of modern information and communication technologies, construction of trans-regional multimedia\ninformation publishing platform. Construction of a municipal pilot units in Group region, for example, through\nconsolidation, Office LANs, corporate networks in electric power communication network, cable TV network,\nrealized with pictures, video, PPT, FLASH animations, WORD documents, WEB pages, video conference streams,\nradio, television, and other media as the carrier's digital communications....
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