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A SEMI-OPEN-LOOP CODING MODE SELECTION ALGORITHM BASED ON EFM AND SELECTED AMR-WB+ FEATURES
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作者 Hong Ying Zhao Shenghui Kuang Jingming 《Journal of Electronics(China)》 2009年第2期274-278,共5页
To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitatio... To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitation) classification are investigated.11 classifying features in the AMR-WB+ codec are selected and 2 novel classifying features,i.e.,EFM(Energy Flatness Measurement) and stdEFM(standard deviation of EFM),are proposed.Consequently,a novel semi-open-loop mode selection algorithm based on EFM and selected AMR-WB+ features is proposed.The results of classifying test and listening test show that the performance of the novel algorithm is much better than that of the AMR-WB+ semi-open-loop coding mode selection algorithm. 展开更多
关键词 Speech/Audio Semi-open-loop coding mode selection Features selection Energy Flat-ness Measurement(EFM)
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Efficient fast mode decision using mode complexity for multi-view video coding 被引量:1
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作者 王凤随 沈庆宏 都思丹 《Journal of Central South University》 SCIE EI CAS 2014年第11期4244-4253,共10页
The variable block-size motion estimation(ME) and disparity estimation(DE) are adopted in multi-view video coding(MVC) to achieve high coding efficiency. However, much higher computational complexity is also introduce... The variable block-size motion estimation(ME) and disparity estimation(DE) are adopted in multi-view video coding(MVC) to achieve high coding efficiency. However, much higher computational complexity is also introduced in coding system, which hinders practical application of MVC. An efficient fast mode decision method using mode complexity is proposed to reduce the computational complexity. In the proposed method, mode complexity is firstly computed by using the spatial, temporal and inter-view correlation between the current macroblock(MB) and its neighboring MBs. Based on the observation that direct mode is highly possible to be the optimal mode, mode complexity is always checked in advance whether it is below a predefined threshold for providing an efficient early termination opportunity. If this early termination condition is not met, three mode types for the MBs are classified according to the value of mode complexity, i.e., simple mode, medium mode and complex mode, to speed up the encoding process by reducing the number of the variable block modes required to be checked. Furthermore, for simple and medium mode region, the rate distortion(RD) cost of mode 16×16 in the temporal prediction direction is compared with that of the disparity prediction direction, to determine in advance whether the optimal prediction direction is in the temporal prediction direction or not, for skipping unnecessary disparity estimation. Experimental results show that the proposed method is able to significantly reduce the computational load by 78.79% and the total bit rate by 0.07% on average, while only incurring a negligible loss of PSNR(about 0.04 d B on average), compared with the full mode decision(FMD) in the reference software of MVC. 展开更多
关键词 multi-view video coding mode decision mode complexity computational complexity
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Efficient FPGA implementation of AES 128 bit for IEEE 802.16e mobile WiMax standards
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作者 P. Rajasekar Dr. H. Mangalam 《Circuits and Systems》 2016年第4期371-380,共10页
In an advancement of communication field, wireless technology plays a predominant role in data transmission. In the timeline of wireless domain, Wi-Fi, Bluetooth, zigbee etc are some of the standards, which are being ... In an advancement of communication field, wireless technology plays a predominant role in data transmission. In the timeline of wireless domain, Wi-Fi, Bluetooth, zigbee etc are some of the standards, which are being used in today’s wireless medium. In addition, the WiMax is introduced by IEEE in IEEE 802.16 for long distance communication, specifically 802.16e standard for mobile WiMax. It is an acronym of Worldwide Interoperability for Microwave Access. It is to be deliver wireless transmission with high quality of service in a secured environment. Since, security becomes dominant design aspect of every communication, a new technique has been proposed in wireless environment. Privacy across the network and access control management is the goal in the predominant aspects in the WiMax protocol. Especially, MAC sub layer should be evaluated in the security architecture. It has been proposed on cryptography algorithm AES that require high cost. Under this scenario, we present the optimized AES 128 bit counter mode security algorithm for MAC layer of 802.16e standards. To design a efficient MAC layer, we adopt the modification of security layers data handling process. As per the efficient design strategy, the power and speed are the dominant factors in mobile device. Since we concentrate mobile WiMax, efficient design is needed for MAC Security layer. Our proposed model incorporates the modification of AES algorithm. The design has been implemented in Xilinx virtex5 device and power has been analyzed using XPower analyzer. This proposed system consumes 41% less power compare to existing system. 展开更多
关键词 DECRYPTION FPGA implementation Electronic code book mode Galois Field Low Power Architecture : AES encryption
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Novel Video Steganography Algorithm Based on Secret Sharing and Error-Correcting Code for H.264/AVC 被引量:5
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作者 Yingnan Zhang Minqing Zhang +2 位作者 Xiaoyuan Yang Duntao Guo Longfei Liu 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2017年第2期198-209,共12页
In this paper, we analyze the video steganography technique, which is used to ensure national security and the confidentiality of the information of governmental agencies and enterprises. Videos may be used to transmi... In this paper, we analyze the video steganography technique, which is used to ensure national security and the confidentiality of the information of governmental agencies and enterprises. Videos may be used to transmit secrets and conduct covert communication. As such, we present an algorithm based on a secret sharing scheme and an Error-Correcting Code(ECC), which combines Grey Relational Analysis(GRA) with a partition mode in video compression standard H.264/AVC. First, we process secret information by secret sharing, and then use an ECC to process the obtained information. Moreover, we choose the Discrete Cosine Transform(DCT) blocks using GRA, and then use rules to hide the pretreated information in DCT coefficients of the video frames. Experimental results indicate that our algorithm has good invisibility, better robustness, good anti-steganalysis ability, and little influence on the bit rate of the video carrier. In addition, the bit error rate is low after attacks such as noise, filtering,or frame loss in the simulation environment. 展开更多
关键词 steganography video secret sharing error-correcting code robustness grey relational analysis partition mode
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