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1.
电视节目制作系统中存在着几种格式的压缩问题 ,对几种压缩方式及其优缺点进行了分析。  相似文献   
2.
Viewing stereoscopic 3D content is typically enabled either by using polarizing or active shutter glasses. In certain cases, some viewers may not wear viewing glasses and hence, it would be desirable to tune the stereoscopic 3D content so that it could be simultaneously watched with and without viewing glasses. In this paper we propose a video post-processing technique which enables good quality 3D and 2D perception of the same content. This is done through manipulation of one view by making it more similar to the other view to reduce the ghosting artifact perceived without viewing glasses while 3D perception is maintained. The proposed technique includes three steps: disparity selection, contrast adjustment, and low-pass filtering. The proposed approach was evaluated through an extensive series of subjective tests, which also revealed good adjustment parameters to suit viewing with and without viewing glasses with an acceptable 3D and 2D quality, respectively.  相似文献   
3.
The dissolution phenomenon of Mn ions in LiMn2O4 (LMO) cathode material for lithium ion batteries (LIBs) was investigated by a first principle calculation using the discrete variational Xα molecular orbital method. It was found that the oxidation number of Mn ions easily increases at high temperatures due to the empty levels of Mn 3d orbitals located in the vicinity of the Fermi energy level of LMO crystal. The changes of density of states (DOS) and Mn‐O bonding properties with doping were examined. Analysis of DOS showed that the substitution of elements with a smaller oxidation number than Mn was found effective in keeping Mn ions at higher oxidation states. From the calculation of bonding properties, the dissolution of Mn was found to be strongly correlated with the covalent nature of Mn‐O bond. Based on the results, we concluded that increasing the covalent character of Mn‐O bond is effective to minimize the dissolution of Mn ions, along with suppressing the formation of Jahn‐Teller‐active Mn3+ by inducing Mn ions at high oxidation state with proper selection of doping elements. © 2012 Wiley Periodicals, Inc.  相似文献   
4.
充分利用深度图序列相邻帧间的局部相似性,并结合H.264帧内预测编码算法,提出了一种适用于深度图序列编码的新方法,即深度图序列的I帧编码采用H.264帧内预测结构而P帧编码采用基于分形理论的压缩方法。首先介绍了分形编码的理论基础,然后通过改进非均匀多层次六边形格点整像素运动搜索(UMHexagonS)方法,提出了一种更适用于分形编码的基于运动矢量场的自适应六边形搜索算法,从而形成了基于分形的深度图P帧预测编码结构。实验结果表明:本文提出的编码系统在很大程度上提高了H.264的编码性能,峰值信噪比差值(BDPSNR)平均提高了3.54dB,编码比特率差值(BDBR)平均降低40.98%,同时编码复杂度也大大降低,平均编码时间减少了85.27%。  相似文献   
5.
徐明 《中国有线电视》2005,(11):1072-1075
随着数字技术的发展,电视节目制作已进入了数字化时代.高校教育电视因资金限制,电视制作设备一直处于陈旧、档次低、老化等状态,DV数字视频制作产品的出现,以其性能优良、经济实用、方便快捷等优势成为教育电视数字化进程的首选设备.介绍常用数字便携DV摄像产品及非线性编辑产品的性能和高校教育电视数字视频构建的平台方案.  相似文献   
6.
Deployments over large geographical areas in the Internet of Things (IoT) pose a major challenge for single‐hop localization techniques, giving rise to applications of multi‐hop localizations. And while many proposals have been made on implementations for multi‐hop localization, a close understanding of its characteristics is yet to be established. Such an understanding is necessary, and is inevitable in extending the reliability of location based services in IoT. In this paper, we study the characteristics of multi‐hop localization and propose a new solution to enhance the performance of multi‐hop localization techniques. We first examine popular assumptions made in simulating multi‐hop localization techniques, and offer rectifications facilitating more realistic simulation models. We identify the introduced errors to follow the Gaussian distribution, and the estimated distance follows the Rayleigh distribution. We next use our simulation model to characterize the effect of the number of hops on localization in both dense and sparse deployments. We find that, contrary to common belief, it is better to use long hops in sparse deployments, while short hops are better in dense deployments – despite the traffic overhead. Finally, we propose a new solution that decreases and manages the overhead generated during the localization process. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
7.
实现了对松下P2素材进行剪辑的功能模块,所涉及文件格式包括MXF,DV,AVCI,MP4,MPEG-4.为达到高效剪辑,采用了MPEG-4帧类型转换、多线程文件读写以及内存映射技术,剪辑均达到了帧精度,耗时短,效果良好.  相似文献   
8.
DV摄像机在旅游中的技术处理与拍摄技巧应用是众多旅游爱好者共同关注的问题,从分析DV摄像机技术特性、摄像中的技术处理和技巧应用等几方面介绍如何拍摄旅游景点中优美独特的风光景色、记录景点的人文景观、捕捉愉快有趣的旅游情景,从而增强旅游摄像画面的表现力,使旅游生活更具意义和情趣.  相似文献   
9.
广播电视常用数字视频编码技术   总被引:1,自引:0,他引:1  
数字化设备在广播电视制作中已经得到运用,而且运用的范围越来越大,从前期拍摄到后期编辑都有数字化的身影.介绍了当前主要电视制作设备中常用数字视频编码技术的国际标准,编码的方式和种类,以及它们的差别.  相似文献   
10.
传感器网络的任务双效节能调度研究   总被引:1,自引:0,他引:1  
能源供应有限性是局限传感器网络的性能和存活寿命的重要因素,本文从传感器网络节点的任务调度出发,提出动态能量管理DPM和动态电压/频率调节DV/FS的双效处理器节能调度算法,即DV/FS-RM和DV/FS-EDF调度算法;在DPM动态控制空闲任务进入休眠的同时,在保证节点的实时性的前提下,通过DV/FS-RM或DV/FS-EDF算法降低处理器频率,达到更好的节能效果.实验显示,该节能任务调度算法使以电池为能源的传感器网络节点的生存期成倍地延长.  相似文献   
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