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Joint depth-motion dense estimation for multiview video coding

JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION 2010年第5-6期21卷 487-497页

作者： Daribo, Ismael Miled, Wided Pesquet-Popescu, Beatrice Telecom ParisTech Signal & Image Proc Dept F-75014 Paris France

The multiview video coding (MVC) extension of H.264/MPEG-4 AVC [1] is one of the most promising visual encoders for three-dimensional television and free viewpoint video applications. In this paper, we propose a joint dense motion/disparity estimation algorithm, designed to replace the classical temporal/inter-view unit within MVC, which uses a block-based motion/disparity estimation. The motion vector fields and the disparity vector fields are therefore simultaneously derived using the stereo-motion consistency constraint in a set theoretic convex optimization framework. The obtained displacement vector fields are then jointly segmented by minimizing a rate-distortion cost function, in line with the multiple reference frame strategy used in H.264/MPEG-4 AVC. Experimental results demonstrate the benefits of the proposed method compared to the separated dense estimation scheme Or the block-based estimation technique. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Multiview video coding Depth Joint motion-depth estimation Total variation Convex optimization H.264/MPEG-4 AVC MVC

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A Novel video coding Strategy in HEVC for Object Detection

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2021年第12期31卷 4924-4937页

作者： Cai, Qi Chen, Zhifeng Wu, Dapeng Oliver Liu, Shan Li, Xiang Univ Florida Dept Elect & Comp Engn Gainesville FL 32608 USA Fuzhou Univ Dept Phys & Informat Engn Fuzhou 350108 Peoples R China Tencent Amer Media Lab Palo Alto CA 94306 USA

Occupying the most significant portion of global data traffic, video is being generated in almost every aspect of our life. Because of its huge volume, we are depending much more heavily on machine intelligence based analysis. In the meantime, video coding technology has been continuously improved for better compression efficiency. However, the state-of-the-art video coding standards, such as H.265/HEVC and versatile video coding (VVC), are still designed assuming that the compressed video will be watched by a human later. Such a design is not optimal when the compressed video will be used by computer vision applications. While the human visual system (HVS) is consistently sensitive to the content with high contrast, the impact of pixels on computer vision algorithms is task driven. For example, because of the different categories of objects used to train detection algorithms, the influence of the same image content on those detectors also varies. Therefore, human oriented video coding strategies may not be optimal when the compressed signal is further processed by algorithms, as the encoder is unaware of the task specific information. In this article, taking object detection as an example, we propose a novel video coding strategy for computer vision. By protecting the information according to its importance for an object detector rather than for the human visual system, our proposed method has the potential to achieve a better object detection performance with the same bandwidth. The main contributions of our paper are: 1) the modeling of the relationship between object detection accuracy and bit rate;2) a back propagation based method to analyze the influence of each pixel on the detection of target objects;3) an object detection oriented bit allocation and codec control parameter determination scheme;4) an evaluation metric to compare the impact of video coding strategies on a given object detector over a predefined range of bit rate. Experimental results demonst

关键词： video coding Object detection Bit rate Encoding Codecs Detectors Visualization HEVC object detection detection accuracy modeling pixel-level impact on detection bit allocation

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Foveation scalable video coding with automatic fixation selection

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2003年第2期12卷 243-254页

作者： Wang, Z Lu, LG Bovik, AC Univ Texas LIVE Austin TX 78712 USA NYU LCV New York NY 10003 USA IBM Corp Thomas J Watson Res Ctr Yorktown Hts NY 10598 USA

Image and video coding is an optimization problem. A successful image and video coding algorithm delivers a good tradeoff between visual quality and other coding performance measures, such as compression, complexity, scalability, robustness, and security. In this paper, we follow two recent trends in image and video coding research. One is to incorporate human visual system (HVS) models to improve the current state-of-the-art of image and video coding algorithms by better exploiting the properties of the intended receiver. The other is to design rate scalable image and video codecs, which allow the extraction of coded visual information at continuously varying bit rates from a single compressed bitstream. Specifically, we propose a foveation scalable video coding (FSVC) algorithm which supplies good quality-compression performance as well as effective rate scalability. The key idea is to organize the encoded bitstream to provide the best decoded video at an arbitrary bit rate in terms of foveated visual quality measurement. A foveation-based HVS model plays an important role in the algorithm. The algorithm is adaptable to different applications, such as knowledge-based video coding and video communications over time-varying, multiuser and interactive networks.

关键词： foveation human visual system image and video quality rate scalable coding video coding wavelet

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Enhanced Bi-Prediction With Convolutional Neural Network for High-Efficiency video coding

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2019年第11期29卷 3291-3301页

作者： Zhao, Zhenghui Wang, Shiqi Wang, Shanshe Zhang, Xinfeng Ma, Siwei Yang, Jiansheng Peking Univ Sch Math Sci Key Lab Math & Its Applt LMAM Beijing 100871 Peoples R China City Univ Hong Kong Dept Comp Sci Hong Kong Peoples R China Peking Univ Inst Digital Media Sch Elect Engn & Comp Sci Beijing 100871 Peoples R China Univ Southern Calif Viterbi Sch Engn Los Angeles CA 90089 USA Capital Normal Univ Beijing Adv Innovat Ctr Imaging Technol Beijing 100048 Peoples R China

In this paper, we propose an enhanced bi-prediction scheme based on the convolutional neural network (CNN) to improve the rate-distortion performance in video compression. In contrast to the traditional bi-prediction strategy which computes the linear superposition as the predictive signals with pixel-to-pixel correspondence, the proposed scheme employs CNN to directly infer the predictive signals in a data-driven manner. As such, the predicted blocks are fused in a nonlinear fashion to improve the coding performance. Moreover, the patch-to-patch inference strategy with CNN also improves the prediction accuracy since the patch-level information for the prediction of each individual pixel can be exploited. The proposed enhanced bi-prediction scheme is further incorporated into the high-efficiency video coding standard, and the experimental results exhibit a significant performance improvement under different coding configurations.

关键词： Encoding video coding Machine learning Image restoration Neural networks Interpolation Image coding Bi-prediction deep neural network inter prediction video coding

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Multiple Description video coding Based on Hierarchical B Pictures

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2009年第4期19卷 511-521页

作者： Zhu, Ce Liu, Minglei Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

A general multiple description video coding (MDVC) framework based on hierarchical B pictures is proposed in this paper. Two or more descriptions are generated by employing the hierarchical B pictures of H.264/AVC scalable extension, where temporal-level-based key pictures are selected in a staggered way among different descriptions. Based on this hierarchical and staggered structure, inter-description redundancy control is studied to achieve a good central/side-distortion-rate tradeoff. Moreover, to better exploit multiple complementary descriptions, a linear combination of received descriptions is employed to optimize decoding results. This proposed MDVC framework is H.264/AVC-compliant for each temporal scalable description. Some existing temporal-splitting MDVC techniques can be considered as a degraded case in the proposed structure. Experimental results validate the effectiveness of the proposed design for MDVC.

关键词： Central/side distortion hierarchical B pictures multiple description coding (MDC) redundancy control video coding

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Recent advances in omnidirectional video coding for virtual reality: Projection and evaluation

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SIGNAL PROCESSING 2018年 146卷 66-78页

作者： Chen, Zhenzhong Li, Yiming Zhang, Yingxue Wuhan Univ Sch Comp Sci State Key Lab Software Engn Wuhan 430072 Hubei Peoples R China Wuhan Univ Sch Remote Sensing & Informat Engn Wuhan 430079 Hubei Peoples R China

In this paper, we review the recent advances in the pipeline of omnidirectional video processing including projection and evaluation. Being distinct from the traditional video, the omnidirectional video, also called panoramic video or 360 degree video, is in the spherical domain, thus specialized tools are necessary. For this type of video, each picture should be projected to a 2-D plane for encoding and decoding, adapting to the input of existing video coding systems. Thus the coding influence of the projection and the accuracy of the evaluation method are very important in this pipeline. Recent advances, such as different projection methods benefiting video coding, specialized video quality evaluation metrics and optimized methods for transmission, are all presented and classified in this paper. In addition, the coding performances under different projection methods are specified. The future trends of omnidirectional video processing are also discussed. (C) 2018 Elsevier B.V. All rights reserved.

关键词： Virtual reality Omnidirectional video video coding Projection Evaluation

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Influence of downsampling filter characteristics on compression performance in wavelet-based scalable video coding

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IET IMAGE PROCESSING 2008年第3期2卷 116-129页

作者： Mrak, M. Zgaljic, T. Izquierdo, E. Univ London Dept Elect Engn London E1 4NS England

The application of different downsampling filters in video coding directly models visual information at lower resolutions and influences the compression performance of a chosen coding system. In wavelet-based scalable video coding the spatial scalability is achieved by the application of wavelets as downsampling filters. However, characteristics of different wavelets influence the performance at targeting spatio-temporal decoding points. An analysis of different downsampling filters in popular wavelet-based scalable video coding schemes is presented. Evaluation is performed for both intra- and inter-coding schemes using wavelets and standard downsampling strategies. On the basis of the obtained results a new concept of inter-resolution prediction is proposed, which maximises the average performance using a combination of standard downsampling filters and wavelet-based coding.

关键词： average performance downsampling scalable video coding visual information wavelets Filters video coding

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Distortion propagation modeling and its applications on frame level quantization control for predictive video coding

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2019年 78卷 398-408页

作者： Yin, Haibing Huang, Xiaofeng Li, Dong Lu, Yu Zhou, Yang Hangzhou Dianzi Univ Sch Commun Engn Hangzhou 310018 Zhejiang Peoples R China

Inter-frame temporal prediction in video coding causes distortion propagation among adjacent frames. As a result, frame level bit allocation and quantization control are intrinsically to be optimized with dependent rate distortion optimization (RDO). Taking inter-frame distortion propagation into consideration, quantization parameter cascading (QPC) is an efficient technique for frame level quantization control in terms of dependent RDO. This paper proposes a temporal distortion propagation model by quantitatively evaluating the temporal distortion dependency. Block-level temporal trajectory is tracked via inter-prediction on down-sampled original frames to construct the temporal analysis chain, and then tree-style dependent analysis is implemented along the trajectory. The amounts of equivalent distortion propagated from the temporally adjacent frames are quantitatively measured. Then, a new distortion model is developed to facilitate measuring the RD (rate distortion) cost in terms of dependent RDO. Finally, a simplified trellis comprised of candidate quantization parameters (Qp) of the frames within one GOP, and the optimal Qp is searched via simplified dynamic programming to achieve global optimization. The simulation results verify that the frame level QPC algorithm achieves 3.46% BD-RATE saving on average, which is contributed by efficient bit allocation along temporal trajectory.

关键词： video coding Rate control Rate distortion optimization Distortion propagation

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Depth Map coding Optimization Using Rendered View Distortion for 3D video coding

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2015年第11期24卷 3534-3545页

作者： Kim, Woo-Shik Ortega, Antonio Lai, Polin Tian, Dong Univ So Calif Los Angeles CA 90089 USA Univ So Calif Dept Elect Engn Los Angeles CA 90089 USA Technicolor Res & Innovat F-35576 Cesson Sevigne France

In order to improve 3D video coding efficiency, we propose methods to estimate rendered view distortion in synthesized views as a function of the depth map quantization error. Our approach starts by calculating the geometric error caused by the depth map error based on the camera parameters. Then, we estimate the rendered view distortion based on the local video characteristics. The estimated rendered view distortion is used in the rate-distortion optimized mode selection for depth map coding. A Lagrange multiplier is derived using the proposed distortion metric, which is estimated based on an autoregressive model. Experimental results show the efficiency of the proposed methods, with average savings of 43% in depth map bitrate as compared with encoding the depth maps using the same coding tools but with the rate-distortion optimization based on the conventional distortion metric.

关键词： Distortion measurement image quality three dimensional TV video coding

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video coding BASED ON AUDIO-VISUAL ATTENTION

VIDEO CODING BASED ON AUDIO-VISUAL ATTENTION

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IEEE International Conference on Multimedia and Expo

作者： Lee, Jong-Seok De Simone, Francesca Ebrahimi, Touradj Ecole Polytech Fed Lausanne Multimedia Signal Proc Grp CH-1015 Lausanne Switzerland

ISBN: (纸本)9781424442904

This paper proposes an efficient video coding method based on audio-visual attention, which is motivated by the fact that cross-modal interaction significantly affects humans' perception of multimedia content. First, we propose an audio-visual source localization method to locate the sound source in a video sequence. Then, its result is used for applying spatial blurring to video frames in order to reduce redundant high-frequency information and achieve coding efficiency. We demonstrate the effectiveness of the proposed method for H.264/AVC coding along with the results of a subjective evaluation.

关键词： video coding audio-visual attention cross-modal interaction source localization H.264/AVC perceived audio-visual quality

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