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New Fragile Watermarking Technique to Identify Inserted Video Objects Using H.264 and Color Features
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作者 Raheem Ogla Eman Shakar Mahmood +1 位作者 Rasha I.Ahmed Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2023年第9期3075-3096,共22页
The transmission of video content over a network raises various issues relating to copyright authenticity,ethics,legality,and privacy.The protection of copyrighted video content is a significant issue in the video ind... The transmission of video content over a network raises various issues relating to copyright authenticity,ethics,legality,and privacy.The protection of copyrighted video content is a significant issue in the video industry,and it is essential to find effective solutions to prevent tampering and modification of digital video content during its transmission through digital media.However,there are stillmany unresolved challenges.This paper aims to address those challenges by proposing a new technique for detectingmoving objects in digital videos,which can help prove the credibility of video content by detecting any fake objects inserted by hackers.The proposed technique involves using two methods,the H.264 and the extraction color features methods,to embed and extract watermarks in video frames.The study tested the performance of the system against various attacks and found it to be robust.The evaluation was done using different metrics such as Peak-Signal-to-Noise Ratio(PSNR),Mean Squared Error(MSE),Structural Similarity Index Measure(SSIM),Bit Correction Ratio(BCR),and Normalized Correlation.The accuracy of identifying moving objects was high,ranging from 96.3%to 98.7%.The system was also able to embed a fragile watermark with a success rate of over 93.65%and had an average capacity of hiding of 78.67.The reconstructed video frames had high quality with a PSNR of at least 65.45 dB and SSIMof over 0.97,making them imperceptible to the human eye.The system also had an acceptable average time difference(T=1.227/s)compared with other state-of-the-art methods. 展开更多
关键词 video watermarking fragile digital watermark copyright protection moving objects color image features h.264
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RTP payload format for H.264/SVC scalable video coding 被引量:7
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作者 WENGER Stephan HANNUKSELA Miska M. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期657-667,共11页
The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design ... The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team’s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC. Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL) and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, in- cluding the design criteria, use cases, signaling and payload structure. 展开更多
关键词 h.264 Advanced video CODING (AVC) Scalable video CODING (SVC) Scalability Real-time transport protocol (RTP) Packetization
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A rate control scheme for H.264 video under low bandwidth channel 被引量:11
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作者 YIN Ming WANG Hong-yuan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期990-995,共6页
The dilemma of the quantization parameter (QP) being involved in both rate control and rate-distortion optimization (RDO) prevents using the traditional rate control scheme. Although some rate control schemes are prop... The dilemma of the quantization parameter (QP) being involved in both rate control and rate-distortion optimization (RDO) prevents using the traditional rate control scheme. Although some rate control schemes are proposed to circumvent the dilemma, the inaccurate prediction model and improper bit allocation deter H.264 application on low bandwidth channel. To resolve this issue, this paper proposes a novel rate control scheme by considering the macroblock (MB) encoding complexity variation and buffer variation and by exploiting the spatio-temporal correlation sufficiently well. Simulations showed that this scheme improves the perceptual quality of the pictures with similar or smaller PSNR deviations when compared to that of rate control in JVT-O016. 展开更多
关键词 video coding h.264 Rate control hRD Bit allocation
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RTP-based broadcast streaming of high definition H.264/AVC video: an error robustness evaluation 被引量:1
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作者 HILLESTAD Odd Inge JETLUND Ola PERKIS Andrew 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期19-26,共8页
In this work, we present an evaluation of the performance and error robustness of RTP-based broadcast streaming of high-quality high-definition (HD) H.264/AVC video. Using a fully controlled IP test bed (Hillestad et ... In this work, we present an evaluation of the performance and error robustness of RTP-based broadcast streaming of high-quality high-definition (HD) H.264/AVC video. Using a fully controlled IP test bed (Hillestad et al., 2005), we broadcast high-definition video over RTP/UDP, and use an IP network emulator to introduce a varying amount of randomly distributed packet loss. A high-performance network interface monitoring card is used to capture the video packets into a trace file. Purpose-built software parses the trace file, analyzes the RTP stream and assembles the correctly received NAL units into an H.264/AVC Annex B byte stream file, which is subsequently decoded by JVT JM 10.1 reference software. The proposed measurement setup is a novel, practical and intuitive approach to perform error resilience testing of real-world H.264/AVC broadcast applications. Through a series of experiments, we evaluate some of the error resilience features of the H.264/AVC standard, and see how they perform at packet loss rates from 0.01% to 5%. The results confirmed that an appropriate slice partitioning scheme is essential to have a graceful degradation in received quality in the case of packet loss. While flexible macroblock ordering reduces the compression efficiency about 1 dB for our test material, reconstructed video quality is improved for loss rates above 0.25%. 展开更多
关键词 h.264/AVC video streaming Error robustness
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RATE CONTROL ALGORITHM FOR H.264 VIDEO ENCODER 被引量:2
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作者 Xue Jinzhu Shen Lansun (Signal & Information Processing Lab, Beijing University of Technology, Beijing 100022) 《Journal of Electronics(China)》 2003年第6期456-460,共5页
This letter proposes a rate control algorithm for H.264 video encoder, which is based on block activity and buffer state. Experimental results indicate that it has an excellent performance by providing much accurate b... This letter proposes a rate control algorithm for H.264 video encoder, which is based on block activity and buffer state. Experimental results indicate that it has an excellent performance by providing much accurate bit rate and better coding efficiency compared with H.264. The computational complexity of the algorithm is reduced by adopting a novel block activity description method using the Sum of Absolute Difference (SAD) of 16× 16 mode, and its robustness is enhanced by introducing a feedback circuit at frame layer. 展开更多
关键词 Rate control video coding h.264
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An H.264/AVC Video Watermarking Scheme in VLC Domain for Content Authentication 被引量:1
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作者 Sun Tanfeng Jiang Xinghao +3 位作者 Lin Zhigao Zhou Yue Lu Huan Wang Shilin 《China Communications》 SCIE CSCD 2010年第6期30-36,共7页
A semi-fragile content authentication algorithm is proposed for low bit-rate H.264/AVC video in VLC domain. Utilizing the intra prediction mode and coded block pattern in VLC domain, the proposed algorithm chooses tho... A semi-fragile content authentication algorithm is proposed for low bit-rate H.264/AVC video in VLC domain. Utilizing the intra prediction mode and coded block pattern in VLC domain, the proposed algorithm chooses those macro-blocks from which the signature is extracted and constructs content signature at macro-block level according to the relationship among the energies of quantized low-frequency coefficients of sub-macroblocks. The signature is embedded by modifying the trailing coefficients. The experimental results show that the proposed algorithm performs well in visual quality impact and keep the bit-rate basically unchanged. In addition, the algorithm can embed signatures into I, P, B slices simultaneously and remarkably enhances the watermark capacity. By verifying the extracted signature, the algorithm can detect and locate video tampering efficiently. 展开更多
关键词 h.264/AVC video watermarking content authentication VLC domain semi-fragile watermarking
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基于H.264无线视频传输系统的研究 被引量:8
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作者 王丽丰 牛建伟 +2 位作者 肖晨 胡建平 杨鑫 《计算机应用与软件》 CSCD 北大核心 2005年第10期139-141,共3页
由于无线信道易错、时变和带限的特点,给视频数据的无线传输带来了巨大的挑战。本文设计了一种带有反馈的无线信道视频传输系统,为了加强系统的抗误码性,重点研究了基于错误隐藏的联合信道率失真算法,对原有视频容错编码方法进行改进,... 由于无线信道易错、时变和带限的特点,给视频数据的无线传输带来了巨大的挑战。本文设计了一种带有反馈的无线信道视频传输系统,为了加强系统的抗误码性,重点研究了基于错误隐藏的联合信道率失真算法,对原有视频容错编码方法进行改进,并提出了一种基于丢包反馈的自适应数据分割选择模式,在低带宽高误码的无线信道环境下,提高了视频图像的质量。 展开更多
关键词 视频编码 无线传输h.264 率失真 数据分割 视频传输系统 无线信道 h.264 视频数据 错误隐藏 编码方法
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Analysis of Video Quality Variation with Different Bit Rates of H.264 Compression 被引量:1
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作者 Yen-Jen Chen Yang-Jen Lin Sheau-Ling Hsieh 《Journal of Computer and Communications》 2016年第5期32-40,共9页
The study applied a charge-coupled device (CCD) camera to send video signals to 4 DaVinci<sup>TM</sup> development boards (TMS320DM6446) of Texas Instruments (TI) to carry out H.264 Baseline Profile video ... The study applied a charge-coupled device (CCD) camera to send video signals to 4 DaVinci<sup>TM</sup> development boards (TMS320DM6446) of Texas Instruments (TI) to carry out H.264 Baseline Profile video coding. One of the development boards coded in the Variable Bit Rate (VBR) mode, and the other three development boards coded in the Constant Bit Rate (CBR) mode. In addition, the constant rates are 2 Mbps, 1.5 Mbps and 1 Mbps respectively. The H.264 video compression files produced by the boards were analyzed via video analysis software (CodecVisa) in the study. This software can analyze and present the compression data characteristics of the video files under each video frame, i.e., bits/MB, QP, and PSNR. In this research, the characteristics of data of each frame under four different compression conditions were compared. Their differences were calculated and averaged, and the standard deviation was evaluated. It was further connected with the values of quality characteristics and the peak signal to noise ratio (PSNR) of each frame to analyze the relation among the frame quality, the compression rate of CBR, as well as the quantitative granularity. The preliminary conclusion of the study is that the compression behaviors of CBRs in different coding sources are adjusted in a specific proportion in order to cope with the change in frame complexity. The frame will be severely damaged by a critical value during the process of network transmission while the source rate is less than the value of the characteristic. 展开更多
关键词 h.264 video Coding CodecVisa PSNR VBR CBR QP
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Content-adaptive robust error concealment for packet-lossy H.264 video streaming
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作者 LIAO Ning YAN Dan QUAN Zi-yi MEN Ai-dong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期41-47,共7页
In this paper, we present a spatio-temporal post-processing error concealment (EC) algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks. It aims at optimizing the subjective quali... In this paper, we present a spatio-temporal post-processing error concealment (EC) algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks. It aims at optimizing the subjective quality of the restored video under the constraints of low delay and computational complexity, which are critical to real-time applications and portable devices having limited resources. Specifically, it takes into consideration the physical property of motion field in order to achieve more meaningful perceptual video quality, in addition to the improved objective PSNR. Further, a simple bilinear spatial interpolation approach is combined with the improved boundary-match (B-M) based temporal EC approach according to texture and motion activity analysis. Finally, we propose a low complexity temporal EC method based on motion vector interpolation as a replacement of the B-M based approach in the scheme under low-computation requirement, or as a complement to further improve the scheme's performance in applications having enough computation resources. Extensive experiments demonstrated that the proposal features not only better reconstruction, objectively and subjectively, than JM benchmark, but also robustness to different video sequences. 展开更多
关键词 ERROR concealment ERROR control h.264/AVC video streaming LOSSY transmission
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H.264/AVC error resilience tools suitable for 3G mobile video services
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作者 柳林 叶修梓 +1 位作者 张三元 张引 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第B08期41-46,共6页
The emergence of third generation mobile system (3G) makes video transmission in wireless environment possible, and the latest 3GPP/3GPP2 standards require 3G terminals support H.264/AVC. Due to high packet loss rate ... The emergence of third generation mobile system (3G) makes video transmission in wireless environment possible, and the latest 3GPP/3GPP2 standards require 3G terminals support H.264/AVC. Due to high packet loss rate in wireless envi- ronment, error resilience for 3G terminals is necessary. Moreover, because of the hardware restrictions, 3G mobile terminals support only part of H.264/AVC error resilience tool. This paper analyzes various error resilience tools and their functions, and presents 2 error resilience strategies for 3G mobile streaming video services and mobile conversational services. Performances of the proposed error resilience strategies were tested using off-line common test conditions. Experiments showed that the proposed error resilience strategies can yield reasonably satisfactory results. 展开更多
关键词 Error resilience tools h.264/AVC 3G mobile video services
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Reversible Data Hiding Based on Run-Level Coding in H.264/AVC Video Streams
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作者 Yi Chen Hongxia Wang Xuyun Zhang 《Computers, Materials & Continua》 SCIE EI 2020年第5期911-922,共12页
This paper presents a reversible data hiding(RDH)method,which is designed by combining histogram modification(HM)with run-level coding in H.264/advanced video coding(AVC).In this scheme,the run-level is changed for em... This paper presents a reversible data hiding(RDH)method,which is designed by combining histogram modification(HM)with run-level coding in H.264/advanced video coding(AVC).In this scheme,the run-level is changed for embedding data into H.264/AVC video sequences.In order to guarantee the reversibility of the proposed scheme,the last nonzero quantized discrete cosine transform(DCT)coefficients in embeddable 4×4 blocks are shifted by the technology of histogram modification.The proposed scheme is realized after quantization and before entropy coding of H.264/AVC compression standard.Therefore,the embedded information can be correctly extracted at the decoding side.Peak-signal-noise-to-ratio(PSNR)and Structure similarity index(SSIM),embedding payload and bit-rate variation are exploited to measure the performance of the proposed scheme.Experimental results have shown that the proposed scheme leads to less SSIM variation and bit-rate increase. 展开更多
关键词 Reversible data hiding run-level coding visual quality bit-rate increase h.264/AVC video streams
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H.264硬件解码核的FPGA实现 被引量:1
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作者 付永庆 姜灵灵 《电视技术》 北大核心 2012年第19期59-63,共5页
针对H.264/AVC的视频解码问题进行了研究,给出了H.264解码核的硬件实现方案,对熵解码CAVLC查表方案进行了优化。详细介绍了句法预测模块、反量化、逆DCT以及帧内预测模块的具体实现结构;并引入流水线、并行处理和状态机处理方法来提高... 针对H.264/AVC的视频解码问题进行了研究,给出了H.264解码核的硬件实现方案,对熵解码CAVLC查表方案进行了优化。详细介绍了句法预测模块、反量化、逆DCT以及帧内预测模块的具体实现结构;并引入流水线、并行处理和状态机处理方法来提高处理速度,实现了解码结构上的优化。该算法在EP2S60F672C5ES FPGA上获得验证,结果表明给出的H.264解码算法是正确的,且有节省硬件资源和较快解码速度的优点。 展开更多
关键词 视频编码标准h.264/AVC h.264解码核 流水线 并行处理 FPGA硬件实现
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Very Low Bit-Rate Video Coding by Combining H.264/AVC Standard and 2-D Discrete Wavelet Transform
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作者 Ali Aghagolzadeh Saeed Meshgini +1 位作者 Mehdi Nooshyar Mehdi Aghagolzadeh 《Wireless Sensor Network》 2010年第4期328-336,共9页
In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is a... In this paper, we propose a new method for very low bit-rate video coding that combines H.264/AVC standard and two-dimensional discrete wavelet transform. In this method, first a two dimensional wavelet transform is applied on each video frame independently to extract the low frequency components for each frame and then the low frequency parts of all frames are coded using H.264/AVC codec. On the other hand, the high frequency parts of the video frames are coded by Run Length Coding algorithm, after applying a threshold to neglect the low value coefficients. Experiments show that our proposed method can achieve better rate-distortion performance at very low bit-rate applications below 16 kbits/s compared to applying H.264/AVC standard directly to all frames. Applications of our proposed video coding technique include video telephony, video-conferencing, transmitting or receiving video over half-rate traffic channels of GSM networks. 展开更多
关键词 video CODING h.264/AVC STANDARD RUN Length CODING Two-Dimensional WAVELET Transform
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Robust spatio-temporal error concealment for packet- lossy H.264 video transmission
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作者 LIAO Ning YAN Dan QUAN Zi-yi MEN Ai-dong 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2006年第3期87-92,共6页
In this article, a spatio-temporal post-processing error concealment algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks has been presented. It aims at optimizing subjective qual... In this article, a spatio-temporal post-processing error concealment algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks has been presented. It aims at optimizing subjective quality of restored video and the conventional objective metric, peak signal-to-noise ratio (PSNR), as well, under the constraints of low delay and computational complexity, which are critical to real-time applications and portable devices having limited resources. Specifically, it takes into consideration physical property of motion to achieve more meaningful perceptual video quality. Further, a content-adaptive bilinear spatial interpolation approach and a temporal error concealment approach are combined under a unified boundary match criterion based on texture and motion activity analysis. Extensive experiments have demonstrated that the proposal not only result in better reconstruction, objectively and subjectively, than the reference software model benchmark, but also results in better robustness to different video sequences. 展开更多
关键词 error concealment error control h.264/JVT video transmission lossy transmission
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Efficient Video Copy Detection: Sequence Matching in the H.264 Compressed Domain
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作者 Christian Kas Henri Nicolas 《通讯和计算机(中英文版)》 2011年第12期1047-1070,共24页
关键词 h.264 复制检测 压缩域 序列匹配 视频拷贝 特征向量 颜色直方图 视频数据库
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H.264标准中的宏块编码模式的时空相关性预测算法
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作者 周敬利 向东 +1 位作者 余胜生 陈加忠 《计算机科学》 CSCD 北大核心 2005年第8期118-120,127,共4页
与以往的各种视频编码标准相比,N.264视频编码标准在编码效率上获得了相当大的提高。但这是以提高编码的计算复杂度为代价的,其中运动估计和模式选择的计算复杂度最大。文中提出一种宏块编码模式的快速预测算法,该算法首先检查根据宏块... 与以往的各种视频编码标准相比,N.264视频编码标准在编码效率上获得了相当大的提高。但这是以提高编码的计算复杂度为代价的,其中运动估计和模式选择的计算复杂度最大。文中提出一种宏块编码模式的快速预测算法,该算法首先检查根据宏块编码模式的时空相关性预测得到的模式,再与相应的阈值进行比较,判断是否结束模式选择过程,而不用检查所有的模式。试验结果表明:在保持相近率失真性能的同时,该算法可以有效地降低编码的计算复杂度。 展开更多
关键词 视频编码 h.264 模式 时空相关性 阂值 编码模式 预测算法 h.264标准 宏块 视频编码标准
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基于FPGA的H.264解码核的实现
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作者 付永庆 姜灵灵 《应用科技》 CAS 2012年第3期9-14,共6页
对H.264/AVC的视频解码问题进行了研究,给出了H.264解码核的硬件实现方案,对熵解码CAVLC查表方案进行了优化.介绍了句法预测模块、反量化、逆DCT以及帧内预测模块的具体实现结构;并引入流水线、并行处理和状态机处理方法来提高处理速度... 对H.264/AVC的视频解码问题进行了研究,给出了H.264解码核的硬件实现方案,对熵解码CAVLC查表方案进行了优化.介绍了句法预测模块、反量化、逆DCT以及帧内预测模块的具体实现结构;并引入流水线、并行处理和状态机处理方法来提高处理速度,实现了解码结构上的优化.本算法在EP2S60F672C5ES FPGA上获得验证,结果表明给出的H.264解码算法是正确的,且有节省硬件资源和较快解码速度的优点. 展开更多
关键词 视频编码标准h.264/AVC h.264解码核 FPGA 句法预测 反量化 逆DCT 帧内预测
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MPEG-2到H.264转码中变换系数转换的优化算法 被引量:4
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作者 谭营营 陈启美 方怀东 《电视技术》 北大核心 2006年第11期7-9,共3页
为采用优势明显的H.264编码,并避免已有的大量MPEG-2非线性视频编缉设备被淘汰,研究了从MPEG-2到H.264转码的转换技术,分析了目前的转换算法,提出了一种DCT系数到H.264整数变换(HT)系数转换的优化算法,并针对不同视频终端的应用需求,分... 为采用优势明显的H.264编码,并避免已有的大量MPEG-2非线性视频编缉设备被淘汰,研究了从MPEG-2到H.264转码的转换技术,分析了目前的转换算法,提出了一种DCT系数到H.264整数变换(HT)系数转换的优化算法,并针对不同视频终端的应用需求,分别给出了保持图像空间分辨率不变和减半时的转换方法。实验表明,该算法可大幅度简化运算,并具有良好的实时性和视频质量。 展开更多
关键词 h.264图像编码 MPEG-2图像编码 压缩域视频转码 MPEG-2到h.264转换算法
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高效视频编码标准-H.264 被引量:5
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作者 钟阳 李文元 《电子测量技术》 2004年第5期22-23,共2页
H.264/AVC是ITU-T的视频编码专家组(VCEG)和ISO/IEC的活动图像编码专家组(MPEG)联合开发的一个最新的视频编码标准。其目的是为了获得很好的图像压缩效果并能适应不同的网络环境。文中对H.264/AVC标准的技术特点进行概要介绍。
关键词 视频编码标准 h.264 h.264/AVC 图像编码 MPEG 图像压缩 ITU—T 活动图 ISO/IEC 高效
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基于3G和H.264技术的无线视频监控系统 被引量:26
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作者 任守华 王胜华 +1 位作者 刘士雷 蒋习旺 《计算机应用研究》 CSCD 北大核心 2010年第4期1554-1556,1559,共4页
针对网络视频监控设备的实际应用需求,融合视频压缩、嵌入式系统和无线通信等相关技术,设计实现了基于3G技术的H.264无线视频监控系统。该监控系统实现了视频数据的采集、压缩与网络传输以及编解码等功能。由于H.264标准中码率控制策略... 针对网络视频监控设备的实际应用需求,融合视频压缩、嵌入式系统和无线通信等相关技术,设计实现了基于3G技术的H.264无线视频监控系统。该监控系统实现了视频数据的采集、压缩与网络传输以及编解码等功能。由于H.264标准中码率控制策略过于强调通用性而没有考虑无线网络的误码率高、抖动性大以及嵌入式终端的处理能力有限的因素,本系统在实现了H.264标准中码率控制策略的基础上进行了优化。实验表明,在码率没有明显增加的情况下,图像PSNR值有所提高,从而较好地实现了码率控制效果。 展开更多
关键词 3G h.264 视频监控系统 码率控制
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