检索结果-内蒙古大学图书馆

Conference on Applications of Digital Image Processing XXXVII

作者： Rerabek, Martin Ebrahimi, Touradj Ecole Polytech Fed Lausanne Multimedia Signal Proc Grp MMSPG Lausanne Switzerland

ISBN: (纸本)9781628412444

Current increasing effort of broadcast providers to transmit UHD (Ultra High Definition) content is likely to increase demand for ultra high definition televisions (UHDTVs). To compress UHDTV content, several alternative encoding mechanisms exist. In addition to internationally recognized standards, open access proprietary options, such as VP9 video encoding scheme, have recently appeared and are gaining popularity. One of the main goals of these encoders is to efficiently compress video sequences beyond HDTV resolution for various scenarios, such as broadcasting or internet streaming. In this paper, a broadcast scenario rate-distortion performance analysis and mutual comparison of one of the latest video coding standards H.265/HEVC with recently released proprietary video coding scheme VP9 is presented. Also, currently one of the most popular and widely spread encoder H.264/AVC has been included into the evaluation to serve as a comparison baseline. The comparison is performed by means of subjective evaluations showing actual differences between encoding algorithms in terms of perceived quality. The results indicate a dominance of HEVC based encoding algorithm in comparison to other alternatives if a wide range of bit-rates from very low to high bit-rates corresponding to low quality up to transparent quality when compared to original and uncompressed video is considered. In addition, VP9 shows competitive results for synthetic content and bit-rates that correspond to operating points for transparent or close to transparent quality video.

关键词： High efficiency Video coding (HEVC) Advanced Video coding (AVC) VP9 WebM subjective quality assessment coding efficiency

来源：评论

学校读者我要写书评

暂无评论

Adaptive Motion Vector Resolution Based on the Rate-Distortion Cost and coding Unit Depth

Adaptive Motion Vector Resolution Based on the Rate-Distorti...

引用

4th IEEE International Advance Computing Conference (IACC)

作者： Cho, Yeon-Jea Ko, Jung-Hoon Yu, Hyeong-Geun Lee, Jai-Hoon Park, Dong-Jo Jun, Sung-Ho Korea Adv Inst Sci & Technol Dept Elect Engn Taejon 305701 South Korea Samsung Elect Co Ltd Dept Syst LSI Business Nongseodong South Korea

ISBN: (纸本)9781479925711

In current research on high-efficiency video coding (HEVC), motion vector resolution is always fixed to 1/4 pixel for the entire video sequence. Inter-coding with a fixed motion vector resolution can decrease the coding efficiency because the statistical properties of the local image are not considered. In this paper, we propose an adaptive decision scheme for motion vector resolution to improve the coding efficiency. The proposed scheme capitalizes on the tendency for a high-pel-precision level to be beneficial in terms of coding efficiency as the coding unit (CU) depth decreases. Also, we determined the strength with a ratedistortion (RD) cost and selected a predefined threshold set per slice level. Simulation results with respect to HM7.0 show that the proposed scheme provides a coding gain of 2.4% for a low-delay structure. Moreover, it was found that the average encoding time is reduced by 5%. The proposed scheme can also improve the coding efficiency at a slightly increased encoding time compared to conventional methods.

关键词： motion vector resolution coding efficiency video coding

来源：评论

学校读者我要写书评

暂无评论

Comparative Assessment of H.265/MPEG-HEVC, VP9, and H.264/MPEG-AVC Encoders for Low-Delay Video Applications 37

Comparative Assessment of H.265/MPEG-HEVC, VP9, and H.264/MP...

引用

Conference on Applications of Digital Image Processing XXXVII

作者： Grois, Dan Marpe, Detlev Tung Nguyen Hadar, Ofer Fraunhofer Heinrich Hertz Inst HHI Image Proc Dept Berlin Germany Ben Gurion Univ Negev Communicat Syst Engn Dept Beer- Sheva Israel

ISBN: (纸本)9781628412444

The popularity of low-delay video applications dramatically increased over the last years due to a rising demand for real-time video content (such as video conferencing or video surveillance), and also due to the increasing availability of relatively inexpensive heterogeneous devices (such as smartphones and tablets). To this end, this work presents a comparative assessment of the two latest video coding standards: H.265/MPEG-HEVC (High-efficiency Video coding), H.264/MPEG-AVC (Advanced Video coding), and also of the VP9 proprietary video coding scheme. For evaluating H.264/MPEG-AVC, an open-source x264 encoder was selected, which has a multi-pass encoding mode, similarly to VP9. According to experimental results, which were obtained by using similar low-delay configurations for all three examined representative encoders, it was observed that H.265/MPEG-HEVC provides significant average bit-rate savings of 32.5%, and 40.8%, relative to VP9 and x264 for the 1-pass encoding, and average bit-rate savings of 32.6%, and 42.2% for the 2-pass encoding, respectively. On the other hand, compared to the x264 encoder, typical low-delay encoding times of the VP9 encoder, are about 2,000 times higher for the 1-pass encoding, and are about 400 times higher for the 2-pass encoding.

关键词： H.265 High efficiency Video coding (HEVC) VP9 H.264 AVC x264 low-delay video coding coding efficiency computational complexity

来源：评论

学校读者我要写书评

暂无评论

AN EFFICIENT VIDEO coding TECHNIQUE USING A NOVEL NON-PARAMETRIC BACKGROUND MODEL

AN EFFICIENT VIDEO CODING TECHNIQUE USING A NOVEL NON-PARAME...

引用

IEEE International Conference on Multimedia and Expo Workshops (ICMEW)

作者： Chakraborty, Subrata Paul, Manoranjan Murshed, Manzur Ali, Mortuza Charles Sturt Univ Sch Comp & Math Bathurst NSW 2795 Australia Federat Univ Sch Informat Technol Gippsland Vic 3842 Australia

ISBN: (纸本)9781479947171

Video coding technique with a background frame, extracted from mixture of Gaussian (MoG) based background modeling, provides better rate distortion performance by exploiting coding efficiency in uncovered background areas compared to the latest video coding standard. However, it suffers from high computation time, low coding efficiency for dynamic videos, and prior knowledge requirement of video content. In this paper, we present a novel adaptive weighted non-parametric (WNP) background modeling technique and successfully embed it into HEVC video coding standard. Being non-parametric (NP), the proposed technique naturally exhibits superior performance in dynamic background scenarios compared to MoG-based technique without a priori knowledge of video data distribution. In addition, the WNP technique significantly reduces noise-related drawbacks of existing NP techniques to provide better quality video coding with much lower computation time as demonstrated through extensive comparative studies against NP, MoG and HEVC techniques.

关键词： Video coding Background model Non-parametric model coding efficiency coding performance

来源：评论

学校读者我要写书评

暂无评论

Adaptive low complexity colour transform for video coding 16

Adaptive low complexity colour transform for video coding

引用

2014 16th IEEE International Workshop on Multimedia Signal Processing, MMSP 2014

作者： Weerakkody, Rajitha Mrak, Marta BBC Research and Development London United Kingdom

ISBN: (纸本)9781479958962

For video compression, the RGB signals are usually converted at the source to a perceptual colour space, followed by chroma sub-sampling, for coding efficiency. This is based on the typically higher human visual system sensitivity to the luminance than chrominance of image signals. However, there are specific applications that demand carrying the full RGB signals through the transmission chain, which may also benefit from lossless colour transforms, for efficient coding. In either case, the best colour transform function is noted to be content dependent, although fixed transforms are typically adopted for convenience. This paper presents a method of dynamically adapting this colour transform function for each picture block, using a class of low complexity lifting based schemes. The performance of the proposed algorithm is compared with a number of fixed colour transform schemes and shows a significant compression gain over native RGB coding and YCoCg transform.

关键词： data compression image colour analysis video coding RGB signals adaptive low complexity colour transform chroma subsampling coding efficiency colour transform schemes complexity lifting based scheme compression gain human visual system image chrominance image luminance perceptual colour space picture block red-green-blue signals video compression Color Complexity theory Decoding Encoding Image color analysis PSNR Transforms

来源：评论

学校读者我要写书评

暂无评论

A novel video coding scheme using a scene adaptive non-parametric background model 16

A novel video coding scheme using a scene adaptive non-param...

引用

2014 16th IEEE International Workshop on Multimedia Signal Processing, MMSP 2014

作者： Chakraborty, Subrata Paul, Manoranjan Murshed, Manzur Ali, Mortuza School of Management and Enterprise University of Southern Queensland QLD Australia School of Computing and Mathematics Charles Sturt University NSW Australia School of Information Technology Federation University GippslandVIC Australia

ISBN: (纸本)9781479958962

Video coding techniques utilising background frames, provide better rate distortion performance by exploiting coding efficiency in uncovered background areas compared to the latest video coding standard. Parametric approaches such as the mixture of Gaussian (MoG) based background modeling has been widely used however they require prior knowledge about the test videos for parameter estimation. Recently introduced non-parametric (NP) based background modeling techniques successfully improved video coding performance through a HEVC integrated coding scheme. The inherent nature of the NP technique naturally exhibits superior performance in dynamic background scenarios compared to the MoG based technique without a priori knowledge of video data distribution. Although NP based coding schemes showed promising coding performances, they suffer from a number of key challenges - (a) determination of the optimal subset of training frames for generating a suitable background that can be used as a reference frame during coding, (b) incorporating dynamic changes in the background effectively after the initial background frame is generated, (c) managing frequent scene change leading to performance degradation, and (d) optimizing coding quality ratio between an I-frame and other frames under bit rate constraints. In this study we develop a new scene adaptive coding scheme using the NP based technique, capable of solving the current challenges by incorporating a new continuously updating background generation process. Extensive experimental results are also provided to validate the effectiveness of the new scheme.

关键词： parameter estimation video coding HEVC integrated coding scheme MoG based background modeling NP based technique bit rate constraints coding efficiency coding quality ratio mixture of Gaussian rate distortion performance scene adaptive nonparametric background model video coding scheme video coding standard Bit rate Encoding PSNR Standards Streaming media Training Video coding Video coding Parameter estimation Bit rate Streaming Video Peak signal-to-noise ratio Rate distortion NP solidified gasoline Nondeterministic polynomial-time hard Functional training code standards code efficiency

来源：评论

学校读者我要写书评

暂无评论

Adaptive tiling algorithm based on highly correlated picture regions for the HEVC standard

Adaptive tiling algorithm based on highly correlated picture...

引用

作者： Silva, Cauane Blumenberg

This Master Thesis proposes an adaptive algorithm that is able to dynamically choose suitable tile partitions for intra- and inter-predicted frames in order to reduce the impact on coding efficiency arising from such partitioning. Tiles are novel parallelismoriented tools that integrate the High efficiency Video coding (HEVC) standard, which divide the frame into independent rectangular regions that can be processed in parallel. To enable the parallelism, tiles break the coding dependencies across their boundaries leading to coding efficiency impacts. These impacts can be even higher if tile boundaries split highly correlated picture regions, because most of the coding tools use context information during the encoding process. Hence, the proposed algorithm clusters the highly correlated picture regions inside the same tile to reduce the inherent coding efficiency impact of using tiles. To wisely locate the highly correlated picture regions, image characteristics and encoding information are analyzed, generating partitioning maps that serve as the algorithm input. Based on these maps, the algorithm locates the natural context break of the picture and defines the tile boundaries on these key regions. This way, the dependency breaks caused by the tile boundaries match the natural context breaks of a picture, then minimizing the coding efficiency losses caused by the use of tiles. The proposed adaptive tiling algorithm, in some cases, provides over 0.4% and over 0.5% of BD-rate savings for intra- and inter-predicted frames respectively, when compared to uniform-spaced tiles, an approach which does not consider the picture context to define the tile partitions. ...

关键词： Digital video coding Microeletrônica High efficiency video coding standard Processamento de imagens Parallelism-oriented tools Tile partitions coding efficiency Dissertação

来源：评论

学校读者我要写书评

暂无评论

A FAST INTRA coding ALGORITHM FOR HEVC

A FAST INTRA CODING ALGORITHM FOR HEVC

引用

IEEE International Conference on Image Processing

作者： Yang Wang Xiaopeng Fan Liang Zhao Siwei Ma Debin Zhao Wen Gao Harbin Inst. of Technol. Harbin China

ISBN: (纸本)9781479957521

High efficiency Video coding (HEVC) is the emerging video coding standard, which provides equivalent subjective quality with about 50% bit rate reduction compared to H.264/AVC High Profile. However, the improvement of coding efficiency is obtained at the expense of increased computational complexity. In this paper, a fast algorithm for HEVC intra coding is proposed. Firstly, a depth range prediction method by exploiting the correlation between the neighboring coding Tree Units (CTUs) is proposed. Secondly, the rate distortion costs and Sum of Absolute Difference with Hadamard transform (HSAD) of recently encoded CUs are used to decide whether current CU will be further divided or not. Finally, only the intra prediction modes (IPMs) with lower precision are employed in the rough mode decision (RMD) and IPMs for rate distortion optimization (RDO) are reduced based on the correlation between neighboring CUs. Experimental results show that our proposed algorithm can achieve average 54% (up to 57%) encoding time saving while causing negligible RD performance loss (1.0% BD-rate increase on average) in All Intra High efficiency test condition compared with HM 10.0.

关键词： Hadamard transforms computational complexity video coding CTU H.264-AVC high-profile HEVC intracoding HSAD IPM RD performance loss RDO RMD bit rate reduction coding efficiency depth range prediction method encoding time saving fast intracoding algorithm high-efficiency video coding intrahigh-efficiency test condition intraprediction mode neighboring coding tree units rate distortion cost rate distortion optimization rough mode decision subjective quality sum-of-absolute difference-Hadamard transform video coding standard Complexity theory Encoding Image coding Prediction algorithms Rate-distortion Signal processing algorithms Video coding HEVC fast algorithm intra mode decision Video coding Rate distortion complexity classes bit rate reduction Hadamard transform remote data object High efficiency video coding Signal processing algorithms Prediction algorithms Complexity theory image coding Integrated Pest Management code efficiency Intra coding

来源：评论

学校读者我要写书评

暂无评论

Reducing Quantization Noise to Boost efficiency and Signal Bandwidth in Delta-Sigma-Based Transmitters

引用

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 2013年第12期61卷 4245-4251页

作者： Ebrahimi, Mohammad Mojtaba Helaoui, Mohamed Univ Calgary Dept Elect Engn IRadio Lab Calgary AB T2N 1N4 Canada Univ Calgary Dept Elect & Comp Engn Calgary AB T2N 1N4 Canada

This paper introduces two new techniques to enhance both efficiency and signal bandwidth in delta-sigma-based transmitters. At first step, a technique called quantization noise reduction (QNR), is introduced to enhance the coding efficiency. By filtering out part of the quantization noise in the whole band of the signal, while the signal envelope is maintained almost constant, the coding efficiency is improved without imposing any additional nonlinearity or distortion to the system. By utilizing this technique for an orthogonal frequency division multiplexing (OFDM) signal with 1.25-MHz bandwidth and 80 times oversampling, with 8.1-dB peak-to-average power ratio (PAPR), the coding efficiency is improved from 8.8% to 14.5% while the signal-to-noise distortion ratio (SNDR) of the system remains 43 dB. In the next step by using a controlled filtering on in-band quantization noise along with QNR technique, the bandwidth of the signal and efficiency are increased simultaneously without losing as much linearity. The second technique is called quantization noise reduction with in-band filtering or (QNRIF). QNRIF is applied on an OFDM signal with 1.25-MHz bandwidth, with the same PAPR and only 16 times oversampling. The result for the coding efficiency is improved from 7.7% to 18.7% with 41-dB SNDR.

关键词： coding efficiency delta-sigma modulator (DSM) peak-to-average power ratio (PAPR) switching-mode power amplifier (SMPA)

来源：评论

学校读者我要写书评

暂无评论

On the efficiency of the shortened error correcting codes

引用

INTERNATIONAL JOURNAL OF ELECTRICAL ENGINEERING EDUCATION 2013年第2期50卷 201-212页

作者： Liaperdos, I. Paraskevas, I. Potirakis, S. M. Technol Educ Inst Kalamata Dept Technol Informat & Telecommun Branch Sparta Sparta Greece Technol Educ Inst Piraeus Dept Elect Athens Greece

Shortening is a widely used technique aiming mainly to reduce the block size of an error correcting code and at the same time to enhance its efficiency. However, due to a common misapprehension, students tend to believe that maximum shortening retains maximum coding efficiency. In this work, an educational approach is presented which eliminates the aforementioned misapprehension. Specifically, the efficiency of the shortened error correcting codes is examined both theoretically and experimentally via simulations.

关键词： coding efficiency error control coding shortened codes

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：