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An optimal quality adaptation mechanism for end-to-end FGS video transmission
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作者 ER Gui-hua 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期119-124,共6页
In this paper, we propose a novel optimal quality adaptation algorithm for MPEG-4 fine granular scalability (FGS)stream over wired network. Our algorithm can maximize perceptual video quality by minimizing video quali... In this paper, we propose a novel optimal quality adaptation algorithm for MPEG-4 fine granular scalability (FGS)stream over wired network. Our algorithm can maximize perceptual video quality by minimizing video quality variation and increasing available bandwidth usage rate. Under the condition that the whole bandwidth evolution is known, we design an optimal algorithm to select layer. When the knowledge of future bandwidth is not available, we also develop an online algorithm based on the optimal algorithm. Simulation showed that both optimal algorithm and online algorithm can offer smoothed video quality evolution. 展开更多
关键词 mpeg-4 fine GRANULAR SCALABILITY (FGS) video streaming transmission QUALITY ADAPTATION
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AUTOMATIC SEGMENTATION OF VIDEO OBJECT PLANES IN MPEG-4 BASED ON SPATIO-TEMPORAL INFORMATION
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作者 XiaJinxiang HuangShunji 《Journal of Electronics(China)》 2004年第3期206-212,共7页
Segmentation of semantic Video Object Planes (VOP's) from video sequence is a key to the standard MPEG-4 with content-based video coding. In this paper, the approach of automatic Segmentation of VOP's Based on... Segmentation of semantic Video Object Planes (VOP's) from video sequence is a key to the standard MPEG-4 with content-based video coding. In this paper, the approach of automatic Segmentation of VOP's Based on Spatio-Temporal Information (SBSTI) is proposed.The proceeding results demonstrate the good performance of the algorithm. 展开更多
关键词 video sequence segmentation video Object Plane (VOP) Based on spatiotemporal information mpeg-4
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Nonlinear Dynamic Analysis of MPEG-4 Video Traffic
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作者 GE Fei CAO Yang WANG Yuan-ni 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第6期1019-1024,共6页
The main research motive is to analysis and to veiny the inherent nonlinear character of MPEG-4 video. The power spectral density estimation of the video trafiic describes its 1/f^β and periodic characteristics.The p... The main research motive is to analysis and to veiny the inherent nonlinear character of MPEG-4 video. The power spectral density estimation of the video trafiic describes its 1/f^β and periodic characteristics.The priraeipal compohems analysis of the reconstructed space dimension shows only several principal components can be the representation of all dimensions. The correlation dimension analysis proves its fractal characteristic. To accurately compute the largest Lyapunov exponent, the video traffic is divided into many parts.So the largest Lyapunov exponent spectrum is separately calculated using the small data sets method. The largest Lyapunov exponent spectrum shows there exists abundant nonlinear chaos in MPEG-4 video traffic. The conclusion can be made that MPEG-4 video traffic have complex nonlinear be havior and can be characterized by its power spectral density,principal components, correlation dimension and the largest Lyapunov exponent besides its common statistics. 展开更多
关键词 mpeg-4 video traffic behavior nonlinear dynamic analysis power spectral density principal components analysis correlation dimension largest Lyapunov exponent
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Trace-Based Analysis of MPEG-4 AVC Video Streams
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作者 Kizouris Panagiotis Papadakis Andreas 《Journal of Computer and Communications》 2019年第1期34-48,共15页
MPEG-4 AVC encoded video streams have been analyzed using video traces and statistical features have been extracted, in the context of supporting efficient deployment of networked and multimedia services. The statisti... MPEG-4 AVC encoded video streams have been analyzed using video traces and statistical features have been extracted, in the context of supporting efficient deployment of networked and multimedia services. The statistical features include the number of scenes composing the video and the sizes of different types of frames, within the overall trace and each scene. Statistical processing has been performed upon the traces and subsequent fitting upon statistical distributions (Pareto and lognormal). Through the construction of a synthetic trace, based upon this analysis, our selections of statistical distribution have been verified. In addition, different types of content, in terms of level of activity (quantified as different scene change ratio) have been considered. Through modelling and fitting, the stability of the main statistical parameters has been verified as well as observations on the dependence of these parameters upon the video activity level. 展开更多
关键词 SYNTHETIC TRAFFIC video TRACE mpeg-4 AVC I and B FRAMES
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基于DSP的MPEG-4视频编码软件优化设计 被引量:5
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作者 焦晓 朱光喜 +1 位作者 赵娟 邱锦波 《电视技术》 北大核心 2003年第10期27-29,共3页
采用TMS320C6201DSP芯片实现了实时的MPEG-4视频编码器,在扼要介绍了MPEG-4算法原理的基础上,探讨了软件优化的技术关键———代码优化方法,并给出了实验结果。
关键词 DSP mpeg-4 视频编码 软件优化 代码优化 DMA传输
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基于MPEG-4的网络化数字视频监控系统 被引量:5
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作者 张益斌 金心宇 《电视技术》 北大核心 2004年第5期76-77,79,共3页
讨论了当前网络数字视频监控系统的发展特点,并结合MPEG-4视频压缩格式,以实际系统为模型,介绍了基于MPEG-4网络监控的系统设计方案及其实现,并讨论了系统的局限性,提出了可行的解决方案。
关键词 网络化数字视频监控系统 mpeg-4标准 自适应传输技术 服务质量
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一种适合MPEG-4传输的IP区分服务网络模型 被引量:1
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作者 陈敏 朱小松 韦岗 《计算机工程与应用》 CSCD 北大核心 2003年第20期53-58,共6页
文章提出了一种改进的适合MPEG-4视频传输区分服务的模型。根据MPEG-4视频流特点和网络的拥塞程度,视频服务器中,采用笔者提出的区分服务标记算法。边缘路由器中,采用笔者提出的区分服务调度算法犤1犦,设计了一种新的区分服务调度器,它... 文章提出了一种改进的适合MPEG-4视频传输区分服务的模型。根据MPEG-4视频流特点和网络的拥塞程度,视频服务器中,采用笔者提出的区分服务标记算法。边缘路由器中,采用笔者提出的区分服务调度算法犤1犦,设计了一种新的区分服务调度器,它动态调节加权服务量,适合在IP区分服务网络中运用,降低实时变比特率突发业务的延时和抖动。实验结果表明,在网络带宽不能保证实时MPEG-4传输所需带宽时,采用该文提出的网络模型,实时传输MPEG-4视频序列,恢复序列的主观效果以及峰值信噪比PSNR都优于传统的尽力而为(Best-effort)方法,并且端对端延时和延时抖动也达到实时传输的要求。 展开更多
关键词 区分服务 视频传输 服务质量 mpeg-4 调度算法
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MPEG-4编、解码器容错技术的研究 被引量:1
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作者 朱小松 余英林 《电视技术》 北大核心 2003年第5期10-12,25,共4页
在分析MPEG-4码流结构的基础上,对编码器提出了两点改进:一是对DCT系数不采用AC预测编码;二是对B帧宏块的4种编码模式全部编码。实验表明,这两点改进在基本不降低编码效率的条件下提高了对错误的抵抗力。在解码端提出了一种既能检测本... 在分析MPEG-4码流结构的基础上,对编码器提出了两点改进:一是对DCT系数不采用AC预测编码;二是对B帧宏块的4种编码模式全部编码。实验表明,这两点改进在基本不降低编码效率的条件下提高了对错误的抵抗力。在解码端提出了一种既能检测本数据包差错又能防止下一数据包头被错误解码的方法。针对B帧差错块的恢复,提出了一种基于运动矢量估计的方法,能有效地解决直接拷贝参考帧相应宏块所引起的图像错位问题。 展开更多
关键词 mpeg-4 码流结构 编码器 DCT系数 AC预测编码 B帧宏块 容错技术 运动矢量估计 图像错位 视频编码
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用改进的MPEG-4分层算法实现网络视频 被引量:1
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作者 石旭利 张兆扬 《微电子学与计算机》 CSCD 北大核心 2002年第3期38-41,共4页
实现网络视频首先要在发送端对连续的图象图形进行压缩编码,其次要将编码的比特流分层表示,第三要解决图象在网上传输时出现的包丢失问题。本文从上述三个方面出发,对MPEG-4分层编码算法进行改进,并用改进的算法实现基于物体的编码和比... 实现网络视频首先要在发送端对连续的图象图形进行压缩编码,其次要将编码的比特流分层表示,第三要解决图象在网上传输时出现的包丢失问题。本文从上述三个方面出发,对MPEG-4分层编码算法进行改进,并用改进的算法实现基于物体的编码和比特流的分层表达;采用传输解码缓存模型实现图象传输的连续性,用优先重传技术解决包丢失问题。实验结果表明,上述理论是实现网络视频的较为优选的方案。 展开更多
关键词 网络视频 mpeg-4 包重传 图像压缩编码
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一类MPEG-4 FGS流视频传输的质量定义及算法 被引量:2
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作者 黄天云 《计算机学报》 EI CSCD 北大核心 2006年第5期751-759,共9页
基于PSNR(MSE)指出了MPEG4FGS流视频客观质量和质量变化指标的相关定义,讨论了视频分段场景基础上的质量最优化问题,通过状态迁移图和动态规划给出FGS流视频的最优传输策略,并且用试验数据对FGS流视频的优化传输的控制粒度及实时传输算... 基于PSNR(MSE)指出了MPEG4FGS流视频客观质量和质量变化指标的相关定义,讨论了视频分段场景基础上的质量最优化问题,通过状态迁移图和动态规划给出FGS流视频的最优传输策略,并且用试验数据对FGS流视频的优化传输的控制粒度及实时传输算法进行了对比分析. 展开更多
关键词 mpeg-4 FGS 质量定义 传输策略 视频分段 场景 状态迁移
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Linux平台多通道MPEG-4视频捕获卡驱动程序的设计与实现
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作者 周敬利 杜大才 余胜生 《计算机工程与科学》 CSCD 2004年第9期25-26,74,共3页
本文在多通道MPEG 4视频捕获卡、LinuxPCI驱动程序以及Vide4Linux的基础上 ,设计并实现了基于LinuxPCI以及以Video4Linux为上层标准接口的视频捕获卡的驱动程序。
关键词 LINUX 视频捕获卡 mpeg-4 video4LINUX LINUX PCI
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一种提高MPEG-4解码器性能的错误定位技术
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作者 郭小清 吴介一 张飒兵 《数据采集与处理》 CSCD 北大核心 2005年第4期478-482,共5页
提出一种基于MPEG-4标准容错措施反向可变长编码RVLC(Reverse variable length coding)的错误发现定位方法(Improved RVLC,IRVLC).IRVLC方法充分利用数据帧的局部信息,对I帧和P帧采用不同的错误再定位策略,克服了标准RVLC策略对可能错... 提出一种基于MPEG-4标准容错措施反向可变长编码RVLC(Reverse variable length coding)的错误发现定位方法(Improved RVLC,IRVLC).IRVLC方法充分利用数据帧的局部信息,对I帧和P帧采用不同的错误再定位策略,克服了标准RVLC策略对可能错误宏块进行保守性丢弃的缺点.IRVLC通过一个适应函数对RVLC不能恢复的宏块进行错误再定位性选择,减少丢弃标准RVLC策略定位范围中的错误宏块数,从而缩小错误扩散的区域,提高解码质量.通过与标准RVLC方法比较可得,IRVLC方法得到了较好的解码质量,平均峰值信噪比(Peak signal-noise rate,PSNR)提高了1~2 dB,证明了IRVLC方法的有效性,且与MPEG-4标准完全兼容. 展开更多
关键词 视频传输 mpeg-4 错误发现定位 反向可变长编码
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CDMA2000无线网络中MPEG-4传输性能评估 被引量:3
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作者 卞定元 冯辉 +1 位作者 胡波 邵谦明 《计算机工程》 CAS CSCD 北大核心 2008年第12期203-205,226,共4页
对CDMA2000无线网络中的MPEG-4视频传输进行了跨层性能评估,研究无线信道误码引起丢包的情况下MPEG-4视频编码参数对经信道传输后解码得到的图像质量的影响。以3GPP2的CDMA2000网络仿真器为基础搭建了软件仿真系统,对不同无线信道模型... 对CDMA2000无线网络中的MPEG-4视频传输进行了跨层性能评估,研究无线信道误码引起丢包的情况下MPEG-4视频编码参数对经信道传输后解码得到的图像质量的影响。以3GPP2的CDMA2000网络仿真器为基础搭建了软件仿真系统,对不同无线信道模型以及不同丢帧率条件下MPEG-4编码参数对视频数据传输的影响进行分析和比较,为跨层优化提供有价值的参考。 展开更多
关键词 CDMA2000无线网络 mpeg-4视频传输 跨层
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基于IPP库的MPEG-4视频传输系统设计 被引量:2
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作者 李嘉 魏静 石江宏 《微计算机信息》 北大核心 2008年第11期9-10,26,共3页
本文以PXA270作为硬件平台,采用基于该系列处理器设计的IPP库作为MPEG-4编解码的基本函数,结合视频采集和回放模块实现了一种视频传输系统。实验结果表明,该方案能有效提高处理器效率并达到实时传输的预期设计效果。
关键词 视频传输 PXA270 IPP mpeg-4
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RTP/RTCP协议下MPEG-4视频流传输系统应用研究 被引量:5
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作者 汪理虎 刘春生 《工业控制计算机》 2006年第3期31-32,共2页
在结合RTP/RTCP协议和MPEG-4视频标准基础上,提出了一种适用于MPEG-4视频流网络传输系统的解决方案,重点介绍了MPEG-4数据的RTP协议封装技术,并对网络传输的相关编程实现做了详细的讨论。
关键词 RTP/RTCP mpeg-4标准 流媒体 视频 网络传输
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Prioritized MPEG-4 Audio-Visual Objects Streaming over the DiffServ
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作者 黄天云 郑婵 《Journal of Electronic Science and Technology of China》 2005年第4期314-320,共7页
The object-based scalable coding in MPEG-4 is investigated, and a prioritized transmission scheme of MPEG-4 audio-visual objects (AVOs) over the DiffServ network with the QoS guarantee is proposed. MPEG-4 AVOs are e... The object-based scalable coding in MPEG-4 is investigated, and a prioritized transmission scheme of MPEG-4 audio-visual objects (AVOs) over the DiffServ network with the QoS guarantee is proposed. MPEG-4 AVOs are extracted and classified into different groups according to their priority values and scalable layers (visual importance). These priority values are mapped to the 1P DiffServ per hop behaviors (PHB). This scheme can selectively discard packets with low importance, in order to avoid the network congestion. Simulation results show that the quality of received video can gracefully adapt to network state, as compared with the ‘best-effort' manner. Also, by allowing the content provider to define prioritization of each audio-visual object, the adaptive transmission of object-based scalable video can be customized based on the content. 展开更多
关键词 video streaming quality of service (QoS) mpeg-4 audio-visual objects (AVOs) DIFFSERV PRIORITIZATION
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基于PC104无人机网络视频系统的构建 被引量:1
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作者 林伟波 裴海龙 《现代电子技术》 2007年第15期40-42,共3页
无人机网络视频系统是无人机的重要组成部分,现在提出了一种基于PC104工控机的网络视频系统构建方案,从视频数据采集、压缩及传输等多个方面探讨无人机网络视频系统的构建过程并给出了网络视频系统主要部分的软件实现方案。最终实现了... 无人机网络视频系统是无人机的重要组成部分,现在提出了一种基于PC104工控机的网络视频系统构建方案,从视频数据采集、压缩及传输等多个方面探讨无人机网络视频系统的构建过程并给出了网络视频系统主要部分的软件实现方案。最终实现了无人机网络视频系统的构建,实验结果表明,基于PC104无人机网络视频系统具有可靠的数据处理、传输、显示质量,可应用于监控、勘测等领域。 展开更多
关键词 无人机 PC104 网络视频 JPEG 实时传输
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Objective Performance Evaluation of Video Segmentation Algorithms with Ground-Truth 被引量:1
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作者 杨高波 张兆扬 《Journal of Shanghai University(English Edition)》 CAS 2004年第1期70-74,共5页
While the development of particular video segmentation algorithms has attracted considerable research interest, relatively little effort has been devoted to provide a methodology for evaluating their performance. In t... While the development of particular video segmentation algorithms has attracted considerable research interest, relatively little effort has been devoted to provide a methodology for evaluating their performance. In this paper, we propose a methodology to objectively evaluate video segmentation algorithm with ground-truth, which is based on computing the deviation of segmentation results from the reference segmentation. Four different metrics based on classification pixels, edges, relative foreground area and relative position respectively are combined to address the spatial accuracy. Temporal coherency is evaluated by utilizing the difference of spatial accuracy between successive frames. The experimental results show the feasibility of our approach. Moreover, it is computationally more efficient than previous methods. It can be applied to provide an offline ranking among different segmentation algorithms and to optimally set the parameters for a given algorithm. 展开更多
关键词 video object segmentation performance evaluation mpeg-4.
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Introduction to the High-Efficiency Video Coding Standard 被引量:1
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作者 Ping Wu Mina Li 《ZTE Communications》 2012年第2期2-8,共7页
The high-efficiency video coding (HEVC) standard is the newest video coding standard currently under joint development by ITU-T Video Coding Experts Group (VCEG) and ISO/IEC Moving Picture Experts Group (MPEG). ... The high-efficiency video coding (HEVC) standard is the newest video coding standard currently under joint development by ITU-T Video Coding Experts Group (VCEG) and ISO/IEC Moving Picture Experts Group (MPEG). HEVC is the next-generation video coding standard after H.264/AVC. The goals of the HEVC standardization effort are to double the video coding efficiency of existing H.264/AVC while supporting all the recognized potential applications, such as, video telephony, storage, broadcast, streaming, especially for large picture size video (4k x 2k). The HEVC standard will be completed as an ISO/iEC and ITU-T standard in January 2013. in February 2012, the HEVC standardization process reached its committee draft (CD) stage. The ever-improving HEVC standard has demonstrated a significant gain in coding efficiency in rate-distortion efficiency relative to the existing H.264/AVC. This paper provides an overview of the technical features of HEVC close to HEVC CD stage, covering high-level structure, coding units, prediction units, transform units, spatial signal transformation and PCM representation, intra-picture prediction, inter-picture prediction, entropy coding and in-loop filtering. The HEVC coding efficiency performances comparing with H.264/AVC are also provided. 展开更多
关键词 HEVC JCTVC AVC H.264 mpeg-2 mpeg-4 STANDARDS video
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Research on video motion object segmentation for content-based application
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作者 包红强 ZHANG Zhao- yang +4 位作者 YU Song-yu WANG Suo-zhong WANG Nu-li FANG Yong WANG Zhi-gang 《Journal of Shanghai University(English Edition)》 CAS 2006年第2期142-143,共2页
With the development of the modern information society, more and more multimedia information is available. So the technology of multimedia processing is becoming the important task for the irrelevant area of scientist... With the development of the modern information society, more and more multimedia information is available. So the technology of multimedia processing is becoming the important task for the irrelevant area of scientist. Among of the multimedia, the visual informarion is more attractive due to its direct, vivid characteristic, but at the same rime the huge amount of video data causes many challenges if the video storage, processing and transmission. 展开更多
关键词 image processing video object segmentation spatiotemporal framework mpeg-4.
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