检索结果-内蒙古大学图书馆

2024 conference on Visual communications and image processing

作者： You, Hongjie Le, Zhendong Giuliani, Nicola Boev, Atanas Alshina, Elena Steinbach, Eckehard Huawei Munich Res Ctr Munich Germany Tech Univ Munich Munich Germany

ISBN: (纸本)9798331529543;9798331529550

Judder is a motion artifact describing a perceptual mismatch between human visual system and discrete movements on a display. Judder is correlated with video frame rates, motion speeds and brightness. It significantly degrades the perceived video quality. We present a framework for modeling judder, where the input frames are processed to generate optical flow and a sensitivity map. Concurrently, a specifically designed attention map is integrated into the process. These components collectively contribute to the creation of a feature map, which is utilized to compute judder scores. The proposed approach explicitly takes into account the video frame rate, resulting in an accurate judder score to predict the subjective mean opinion scores ultimately. Our assessment of the proposed framework on an HDR video dataset shows that judderness is highly influenced by the frame rate and, to some extent, by motion speed and brightness. The prediction of perceived quality scores shows improvement compared to the baseline framework.

关键词： judder perceptual quality video frame rate motion artifact high dynamic range

来源：评论

学校读者我要写书评

暂无评论

Controllable Space-Time video Super-Resolution via Enhanced Bidirectional Flow Warping

Controllable Space-Time Video Super-Resolution via Enhanced ...

引用

IEEE International conference on Visual communications and image processing (VCIP)

作者： Zhang, Yuantong Wang, Huairui Chen, Zhenzhong Wuhan Univ Sch Remote Sensing & Informat Engn Wuhan Peoples R China

ISBN: (纸本)9781665475921

Space-time video super-resolution targets to increase a given video's frame rate and resolution simultaneously. Although existing approaches have made great progress, most of them still suffer from the inaccurate approximation of large motions or fail to generate temporal consistent motion trajectory. To alleviate these problems, we carefully review the characteristics of different optical flow warping strategies, integrating and enhancing them to achieve more robust capabilities for handling extreme motions and time-modulated interpolation. Specifically, we utilize enhanced backward warping to perform alignment, mine space-time information across low resolution input frames, and propose an enhanced forward warping strategy to interpolate arbitrary intermediate frames. Furthermore, the proposed model can be trained end-to-end and produce intermediate results at any time by merely supervising the center moment. Experimental results show that the proposed algorithm performs favorably against the state-of-the-art methods in objective metrics and subjective visual effects.

关键词： video Super-Resolution video Interpolation Bidirectional Flow Warping

来源：评论

学校读者我要写书评

暂无评论

Adaptive mesh generation for mesh-based image coding using node elimination approach

Adaptive mesh generation for mesh-based image coding using n...

引用

IEEE International conference on communications (ICC 2005)

作者： Kocharoen, P Ahmed, KM Rajatheva, RMAP Fernando, WAC Asian Inst Technol Telecommun Program Pathum Thani 12120 Thailand

ISBN: (纸本)0780389387

In this paper, a new procedure for generating a mesh structure of image representation has been proposed. The proposed algorithm employs a feature map extraction with a specific threshold level to place initial nodes densely in regions that contain high frequency features and nodes are placed coarsely in smooth regions. After that, many insignificant nodes are removed using node elimination scheme. The proposed algorithm is well suited for usage at very low bit-rate image and video coding as processing results have demonstrated that it provides a good subjective and objective image quality at a lower number of required nodes. Moreover, comparison shows that the proposed method provides comparable image quality while requiring fewer mesh nodes than the several existing methods.

关键词： mesh-based image coding very low bit-rate image coding content-based meshes content-adaptive mesh generation

来源：评论

学校读者我要写书评

暂无评论

Recursive wavelet filters for video coding

Recursive wavelet filters for video coding

引用

conference on Visual communications and image processing 2005

作者： Wang, DM Zhang, L Vincent, A Commun Res Ctr Ottawa ON K2H 8S2 Canada

ISBN: (纸本)0819459763

Recursive wavelet filters and an alternative algorithm for implementing wavelet transform are presented in this paper. The recursive filters use previously calculated (past) wavelet coefficients as inputs to calculate the current wavelet coefficient, and provide the same transform results as convolutional FIR and lifting wavelet filters. The coefficients of the recursive filters are derived from those of conventional FIR wavelet filters. The wavelet transform with recursive filters requires a smaller amount of memory and is easy to implement in hardware. Another important advantage of the recursive filters is that perfect reconstruction can be easily achieved using recursive wavelet filters if a sequence of pixels to be transformed is extended by boundary pixel repetition. Boundary pixel repetition can be more efficient than the widely used method of symmetric extension for image and video coding.

关键词： wavelet transform wavelet filter video coding image coding

来源：评论

学校读者我要写书评

暂无评论

Graph-based No-reference video Quality Assessment Using Spatial Features 15

Graph-based No-reference Video Quality Assessment Using Spat...

引用

15th International conference on Signal processing and communications (SPCOM)

作者： Suresh, N. Channappayya, Sumohana S. IIT Hyderabad Dept Artificial Intelligence Hyderabad Telangana India IIT Hyderabad Dept Elect Engn Hyderabad Telangana India

ISBN: (纸本)9798350350463;9798350350456

In this work, we explore the efficacy of graphs for representing video sequences in the context of no-reference video quality assessment (NR-VQA). Specifically, we address the problem of predicting video quality from frame-level spatial quality scores by using them as node features. We implicitly capture temporal dependency among the nodes through an appropriate choice of the graph adjacency matrix. A graph convolutional network (GCN) that accepts the graph video representation as its input is trained to predict mean opinion scores (MOS). We experiment with several NR image quality assessment (NR-IQA) algorithms that include Natural image Quality Evaluator (NIQE), Multi-scale image Quality Transformer (MUSIQ), Codebook Representation for No-Reference image Assessment (CORNIA), and Neural image Assessment (NIMA) for predicting spatial quality. The proposed NR-VQA algorithm is evaluated on four user-generated VQA datasets on which it showed a consistent improvement over directly using spatial quality scores for regression. These improvements suggest that graph-based video representation is promising for the NR-VQA task.

关键词： Graph convolution network (GCN) No-reference video quality assessment (NR-VQA) IQA for VQA

来源：评论

学校读者我要写书评

暂无评论

Visual Media Production

引用

IEE PROCEEDINGS-VISION image AND SIGNAL processing 2005年第4期152卷 385-386页

作者： Grau, O Hilton, A Univ Surrey Visual Media Res Grp Guildford GU2 5XH Surrey England

Comments on extended versions of selected research papers from the 1st IEE European conference on Visual Media Production in London, England. Presentation of novel methods for image and video processing fundamental to many activities in production and post-production; Research on the reconstruction of people for animation production; Discussion of topics contributing to visual content production.

关键词： MOTION pictures -- Production & direction video recordings -- Production & direction DIGITAL media

来源：评论

学校读者我要写书评

暂无评论

Linear filtering of image subbands for low complexity postprocessing of decoded color images

Linear filtering of image subbands for low complexity postpr...

引用

conference on image and video communications and processing 2005

作者： Bayazit, U Isik Univ Buyukdere Caddesi TR-34398 Istanbul Turkey

ISBN: (纸本)0819456586

In [1], image adaptive linear minimum mean squared error (LMMSE) filtering was proposed as an enhancement layer color image coding technique that exploited the statistical dependencies among the luminance/chrominance or Karhunen Loeve Transform (KLT) coordinate planes of a lossy compressed color image to enhance the red, blue, green (RGB) color coordinate planes of that image. In the current work, we propose the independent design and application of LMMSE filters on the subbands of a color image as a low complexity solution. Towards this end, only the coordinates of the neighbors of the filtered subband coefficient, that are sufficiently correlated with the corresponding coordinate of the filtered subband coefficient, are included in the support of the filter for each subband. Additionally, each subband LMMSE filter is selectively applied only on the high variance regions of the subband. Simulation results show that, at the expense of an insignificant increase in the overhead rate for the transmission of the coefficients of the filters and with about the same enhancement gain advantage, subband LMMSE filtering offers a substantial complexity advantage over fullband LMMSE filtering.

关键词： postprocessing linear filtering color image coding enhancement layer subband wavelet transform

来源：评论

学校读者我要写书评

暂无评论

Visually Optimized Two-Pass Rate Control for video Coding Using the Low-Complexity XPSNR Model

Visually Optimized Two-Pass Rate Control for Video Coding Us...

引用

IEEE International conference on Visual communications and image processing (VCIP) - Visual communications in the Era of AI and Limited Resources

作者： Helmrich, Christian R. Zupancic, Ivan Brandenburg, Jens George, Valeri Wieckowski, Adam Bross, Benjamin Fraunhofer Heinrich Hertz Inst HHI Video Commun & Applicat Grp Einsteinufer 37 D-10587 Berlin Germany

ISBN: (纸本)9781728185514

Two-pass rate control (RC) schemes have proven useful for generating low-bitrate video-on-demand or streaming catalogs. Visually optimized encoding particularly using latest-generation coding standards like Versatile video Coding (VVC), however, is still a subject of intensive study. This paper describes the two-pass RC method integrated into version 1 of VVenC, an open VVC encoding software. The RC design is based on a novel two-step rate-quantization parameter (R-QP) model to derive the second-pass coding parameters, and it uses the low-complexity XPSNR visual distortion measure to provide numerically as well as visually stable, perceptually R-D optimized encoding results. Random-access evaluation experiments confirm the improved objective as well as subjective performance of our RC solution.

关键词： QoE rate control video coding VoD VQA VVC

来源：评论

学校读者我要写书评

暂无评论

Encoder-Decoder Joint Enhancement for video Chat

Encoder-Decoder Joint Enhancement for Video Chat

引用

IEEE International conference on Visual communications and image processing (VCIP) - Visual communications in the Era of AI and Limited Resources

作者： Zhang, Zhenghao Wang, Zhao Ye, Yan Wang, Shiqi Zheng, Changwen Univ Chinese Acad Sci Beijing Peoples R China Alibaba Grp Hangzhou Peoples R China City Univ Hong Kong Hong Kong Peoples R China Chinese Acad Sci Inst Software Beijing Peoples R China

ISBN: (纸本)9781728185514

video chat becomes more and more popular in our daily life. However, how to provide a high-quality video chat with the limited bandwidth is a key challenging task. In this paper, beyond the state-of-the-art video compression system, we propose an encoder-decoder joint enhancement algorithm for the video chat. In particular, the sparse map of the original frame is extracted at the encoder side and signaled to the decoder, which is utilized together with the sparse map of the decoded frame to obtain the boundary transformation map. In this manner, the boundary transformation map represents the key difference between the original frame and the decoded frame and hence can be used to enhance the decoded frame. Experimental results show that the proposed algorithm brings clear subjective and objective quality improvements. At the same quality, the proposed algorithm can achieve 35% bitrate savings compared to the VVC.

关键词： Signal encoding

来源：评论

学校读者我要写书评

暂无评论

A Processor for MPEG decoder SOC: A software/hardware co-design approach

A Processor for MPEG decoder SOC: A software/hardware co-des...

引用

conference on image and video communications and processing 2005

作者： Yu, GJ Yao, QD Liu, P Jiang, ZD Li, FP Zhejiang Univ Dept Informat Sci & Elect Engn Hangzhou 310027 Peoples R China

ISBN: (纸本)0819456586

Media processing such as real-time compression and decompression of video signal is now expected to be the driving force in the evolution of media processor. in this paper, a hardware and software co-design approach is introduced for a 32-bit media processor: MediaDsp3201 (MD32), which is realized in 0.18 mu m TSMC, 200MHz and can achieve 200 million multiply-accumulate (MAC) operations per second. In our design, we have emerged RISC and DSP into one processor (RISC/DSP). Based on the analysis of inherent characteristics of video processing algorithms, media enhancement instructions are adopted into MD32'instruction set. The media extension instructions are physically realized in the processor core, and improve video processing performance effectively with negligible additional hardware cost (2.7%). Considering the high complexity of the operation for media instructions, technology named scalable super pipeline is used to resolve problem of the time delay of pipeline stage (mainly EX stage). Simulation results show that our method can reduce more than 31% and 23% instructions for IDCT compared to MMX and SSE's implementation [5] and 40% for MC compared to MMX's implementation.

关键词： video processor video compression Hardware/Software co-design SIMD

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：