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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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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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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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Video Enhancement Network Based on CNN and Transformer
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作者 YUAN Lang HUI Chen +3 位作者 WU Yanfeng LIAO Ronghua JIANG Feng GAO Ying 《ZTE Communications》 2024年第4期78-88,共11页
To enhance the video quality after encoding and decoding in video compression,a video quality enhancement framework is pro-posed based on local and non-local priors in this paper.Low-level features are first extracted... To enhance the video quality after encoding and decoding in video compression,a video quality enhancement framework is pro-posed based on local and non-local priors in this paper.Low-level features are first extracted through a single convolution layer and then pro-cessed by several conv-tran blocks(CTB)to extract high-level features,which are ultimately transformed into a residual image.The final re-constructed video frame is obtained by performing an element-wise addition of the residual image and the original lossy video frame.Experi-ments show that the proposed Conv-Tran Network(CTN)model effectively recovers the quality loss caused by Versatile Video Coding(VVC)and further improves VVC's performance. 展开更多
关键词 attention fusion mechanism h.266/VVC TRANSFORMER video coding video quality enhancement
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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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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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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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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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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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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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An Introduction to High Efficiency Video Coding Range Extensions
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作者 Bin Li Jizheng Xu 《ZTE Communications》 2016年第1期12-18,共7页
High Efficiency Video Coding (HEVC) is the latest international video coding standard, which can provide the similar quality with about half bandwidth compared with its predecessor, H.264/MPEG?4 AVC. To meet the requi... High Efficiency Video Coding (HEVC) is the latest international video coding standard, which can provide the similar quality with about half bandwidth compared with its predecessor, H.264/MPEG?4 AVC. To meet the requirement of higher bit depth coding and more chroma sampling formats, range extensions of HEVC were developed. This paper introduces the coding tools in HEVC range extensions and provides experimental results to compare HEVC range extensions with previous video coding standards. Ex?perimental results show that HEVC range extensions improve coding efficiency much over H.264/MPEG?4 AVC High Predictive profile, especially for 4K sequences. 展开更多
关键词 h.265 high Efficiency video coding(hEVC) MPEG-h range extensions video compression
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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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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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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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Enhanced Adaptive Approach of Video Coding at Very Low Bit Rate Using MSPIHT Algorithm
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作者 C. Ravichandran N. Malmurugan 《Circuits and Systems》 2016年第8期1233-1241,共9页
Nowadays video coding approach is a major key in many applications for easy transmission and storage consumption. The process of transformation is based on the empirical wavelet transform (EWT). The encoding process o... Nowadays video coding approach is a major key in many applications for easy transmission and storage consumption. The process of transformation is based on the empirical wavelet transform (EWT). The encoding process of video data provides secure and less consumption of storage and the reconstruction process consists of the reverse process with the extraction. In this paper, the coding of video is carried out at a very low bit rate with the enhancement of performance by proposing an approach of modified Set Partitioning in Hierarchical Tree (MSPIHT). This method encodes the high frequency frames with the scheduling of wavelet transform for efficient performances of encoding and improves the ability of both the frequency and time. By applying empirical wavelet transform on each video frame, the component of video frequency is extracted and the low frequency frame is encoded by the H.264/AVC standard. The low coefficient values are ignored in applying the threshold and in the reconstruction process, HBLPCE method is used for imaging enhancement. The simulation of the proposed approach analysis shows better performance in reliable process and efficiency when compared to existing. 展开更多
关键词 video coding h.264 Standard Empirical Wavelet Transform PARTITION SPIhT hBLPCE
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Research on Remote Video Monitoring System Used for Numerical Control Machine Tools Based on Embedded Technology 被引量:1
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作者 LIU Quan QU Xuehong ZHOU Henglin LONG Yihong (School of Information Engineering,Wuhan University of Technology,Wuhan 430070,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期617-620,共4页
This paper designed an embedded video monitoring system using DSP (Digital Signal Processing ) and ARM (Ad- vanced RISC Machine).This system is an important part of self-service operation of numerical control machine ... This paper designed an embedded video monitoring system using DSP (Digital Signal Processing ) and ARM (Ad- vanced RISC Machine).This system is an important part of self-service operation of numerical control machine tools,At first the analog input signals from the CCD(Charge Coupled Device) camera are transformed into digital signals,and then output to the DSP system,where the video sequence is encoded according to the new generation image compressing standard called H.264.The code will be transmitted to the ARM system through xBus,and then be packed in the ARM system and transmitted to the client port through the gateway.Web technology,embedded technology and image compressing as well as coding technology are integrated in the system,which can be widely used in self-service operation of numerical control machine tools and intelligent robot control areas. 展开更多
关键词 EMBEDDED video monitoring h.264 QOS(quality of service)
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Rate Control Algorithm of Wireless Video Based on Visual Saliency Map Model 被引量:1
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作者 阮若林 胡瑞敏 +1 位作者 李忠明 尹黎明 《China Communications》 SCIE CSCD 2011年第7期105-110,共6页
In order to further improve the efficiency of video compression, we introduce a perceptual characteristics of Human Visual System (HVS) to video coding, and propose a novel video coding rate control algorithm based on... In order to further improve the efficiency of video compression, we introduce a perceptual characteristics of Human Visual System (HVS) to video coding, and propose a novel video coding rate control algorithm based on human visual saliency model in H.264/AVC. Firstly, we modifie Itti's saliency model. Secondly, target bits of each frame are allocated through the correlation of saliency region between the current and previous frame, and the complexity of each MB is modified through the saliency value and its Mean Absolute Difference (MAD) value. Lastly, the algorithm was implemented in JVT JM12.2. Simulation results show that, comparing with traditional rate control algorithm, the proposed one can reduce the coding bit rate and improve the reconstructed video subjective quality, especially for visual saliency region. It is very suitable for wireless video transmission. 展开更多
关键词 human visual system saliency map model wireless video coding rate control h.264/AVC
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Color compensation for multi-view video coding based on diversity of cameras 被引量:1
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作者 Jun-yan HUO Yi-lin CHANG +1 位作者 Hai-tao YANG Shuai WAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第12期1631-1637,共7页
A novel color compensation method for multi-view video coding (MVC) is proposed, which efficiently exploits the inter-view dependencies between views with the existence of color mismatch caused by the diversity of cam... A novel color compensation method for multi-view video coding (MVC) is proposed, which efficiently exploits the inter-view dependencies between views with the existence of color mismatch caused by the diversity of cameras. A color compensation model is developed in RGB channels and then extended to YCbCr channels for practical use. A modified inter-view reference picture is constructed based on the color compensation model, which is more similar to the coding picture than the original inter-view reference picture. Moreover, the color compensation factors can be derived in both encoder and decoder, therefore no additional data need to be transmitted to the decoder. The experimental results show that the proposed method improves the coding efficiency of MVC and maintains good subjective quality. 展开更多
关键词 Multi-view video coding (MVC) h.264/AVC Color compensation Diversity of cameras
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Fragile video watermarking technique by motion field embedding with rate-distortion minimization 被引量:6
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作者 KUO Tien-ying LO Yi-chung 《通讯和计算机(中英文版)》 2009年第1期16-23,共8页
关键词 视频水印技术 计算机技术 安全技术 函数
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