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A wavelet video coding algorithm with balanced significance probability tree based on energy weighting

MULTIMEDIA TOOLS AND APPLICATIONS 2019年第21期78卷 30877-30893页

作者： Song, Chuan-Ming Fu, Bo Wang, Xiang-Hai Fu, Ming-Zhe Liaoning Normal Univ Sch Comp & Informat Technol Dalian 116029 Peoples R China Dalian Univ Technol Sch Comp Sci & Technol Dalian 116024 Peoples R China Nanjing Univ State Key Lab Novel Software Technol Nanjing 210093 Jiangsu Peoples R China

This work presents a 3-D wavelet video coding algorithm. By analyzing the contribution of each biorthogonal wavelet basis to reconstructed signal's energy, we weight each wavelet subband according to its basis energy. Based on distribution of weighted coefficients, we further discuss a 3-D wavelet tree structure named balanced significance probability tree, which places the coefficients with similar probabilities of being significant on the same layer. It is implemented by using hybrid spatial orientation tree and temporal-domain block tree. Subsequently, a novel 3-D wavelet video coding algorithm is proposed based on the energy-weighted balanced significance probability tree. Experimental results illustrate that our algorithm always achieves good reconstruction quality for different classes of video sequences. Compared with asymmetric 3-D orientation tree, the average peak signal-to-noise ratio (PSNR) gain of our algorithm are 1.24dB, 2.54dB and 2.57dB for luminance (Y) and chrominance (U,V) components, respectively. Compared with temporal-spatial orientation tree algorithm, our algorithm gains 0.38dB, 2.92dB and 2.39dB higher PSNR separately for Y, U, and V components. In addition, the proposed algorithm requires lower computation cost than those of the above two algorithms.

关键词： video coding Scalable coding 3-D wavelet transform Weighted tree Significant coefficient

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Adaptive Downsampling for High-Definition video coding

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2014年第3期24卷 480-488页

作者： Dong, Jie Ye, Yan InterDigital Commun Inc San Diego CA 92121 USA

Previous research has shown that downsampling prior to encoding and upsampling after decoding can improve the rate-distortion (R-D) performance compared with directly coding the original video using standard technologies, e.g., JPEG and H.264/AVC, especially at low bit rates. This paper proposes a practical algorithm to find the optimal downsampling ratio that balances the distortions caused by downsampling and coding, thus achieving the overall optimal R-D performance. Given the optimal sampling ratio, dedicated filters for down-and upsampling are also designed. Simulations show this algorithm improves the R-D performance over a wide range of bit rates.

关键词： Advanced video coding (AVC) downsampling H.264 video coding

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Object-oriented H.263 compatible video coding platform for conferencing applications

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1998年第1期16卷 42-55页

作者： Hartung, J Jacquin, A Pawlyk, J Rosenberg, J Okada, H Crouch, PE AT&T Bell Labs Lucent Technol Murray Hill NJ 07974 USA Sharp Corp Multimedia Syst Business Dev Ctr Chiba Japan AT&T Corp Global Videophone Syst Grp Holmdel NJ 07733 USA

This paper describes a prototype video coding platform(1) meant for the conception and testing of multimedia products such as next-generation videophones, The platform is largely based on ITU-T Recommendation H.263, with a number of additional object-oriented quality enhancement features which make it especially well suited for very low bit-rate coding of "head-and-shoulders" video material typical of real-time multimedia applications, video teleconferencing, and video telephony, These features consist of: 1) segmentation into objects of interest, 2) segmentation-based prefiltering, 3) model-assisted rate control, 4) adaptive vector quantization, and finally 5) segmentation-based postfiltering, In the spirit of Recommendation H.263, these enhancements are modular and can be selectively turned on or off, thereby enabling a wide variety of coding modes.

关键词： H.263 object-oriented coding video coding video conferencing

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Deep Learning-Based Luma and Chroma Fractional Interpolation in video coding

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IEEE ACCESS 2019年 7卷 112535-112543页

作者： Pham, Chi Do-Kim Zhou, Jinjia Hosei Univ Grad Sch Sci & Engn Tokyo 1848584 Japan JST PRESTO Tokyo 3320012 Japan

Motion compensated prediction is one of the essential methods to reduce temporal redundancy in inter coding. The target of motion compensated prediction is to predict the current frame from the list of reference frames. Recent video coding standards commonly use interpolation filters to obtain sub-pixel for the best matching block located in the fractional position of the reference frame. However, the fixed filters are not flexible to adapt to the variety of natural video contents. Inspired by the success of Convolutional Neural Network (CNN) in super-resolution, we propose CNN-based fractional interpolation for Luminance (Luma) and Chrominance (Chroma) components in motion compensated prediction to improve the coding efficiency. Moreover, two syntax elements indicate interpolation methods for the Luminance and Chrominance components, have been added to bin-string and encoded by CABAC using regular mode. As a result, our proposal gains 2.9%, 0.3%, 0.6% Y, U, V BD-rate reduction, respectively, under low delay P configuration.

关键词： Convolution neural network (CNN) fractional interpolation video coding motion compensated prediction

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Spatial and temporal data parallelization of the H.261 video coding algorithm

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2001年第1期11卷 91-104页

作者： Yung, NHC Leung, KK Univ Hong Kong Dept Elect & Elect Engn Hong Kong Hong Kong Peoples R China

In this paper, the parallelization of the H.261 video coding algorithm on the IBM SP2(R) multiprocessor system is described. The effect of parallelizing computations and communications in the spatial, temporal, and both spatial-temporal domains are considered through the study of frame rate, speedup, and implementation efficiency, which are modeled and measured with respect to the number of nodes (n) and parallel methods used. Four parallel algorithms were developed, of which the first two exploited the spatial parallelism in each frame, and the last two exploited both the temporal and spatial parallelism over a sequence of frames, The two spatial algorithms differ in that one utilizes a single communication master, while the other attempts to distribute communications across three masters. On the other hand, the spatial-temporal algorithms use a pipeline structure for exploiting the temporal parallelism together with either a single master or multiple masters. The best median speedup (frame rate) achieved was close to 15 [15 frames per second (fps)] for 552 x 240 video on 24 nodes, and 13 (37 fps) for QCIF video, by the spatial algorithm with distributed communications. For n < 10, the single-master spatial algorithm performs better with efficiency up to 90%, while the multiple-master spatial algorithm is superior for n > 10, with efficiency up to 70%. The spatial-temporal algorithms achieved average speedup performance, but are most scalable for large n.

关键词： domain decomposition spatial parallelism speedup temporal parallelism video coding

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Visual JND: A Perceptual Measurement in video coding

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IEEE ACCESS 2019年 7卷 29014-29022页

作者： Yuan, Di Zhao, Tiesong Xu, Yiwen Xue, Hong Lin, Liqun Fuzhou Univ Coll Phys & Informat Engn Fuzhou 350116 Fujian Peoples R China

Humans cannot perceive the minimal level of difference in the pixel variation. To overcome the problem, the concept of just-noticeable difference (JND) was proposed. JND measures the minimal amount that must be changed for the variation to be detectable by humans. However, JND characteristics were not considered in the traditional perceptual measurements. In this paper, we provide a comprehensive survey of the latest JND-related studies. First, we provide an extensive overview of JND models. JND models comprise human visual system characteristics and masking effects. Next, we introduce the applications of JND models in the perceptual quality evaluation and video compression coding, especially in applying machine-learning techniques to JND prediction. In addition to a thorough summary of the recent progress and applications of JND, we summarize some unsolved technical challenges. We believe that our overview and findings can provide some insights into the related issues and future research directions in video coding.

关键词： Just noticeable difference (JND) human visual system (HVS) machine learning perceptual measurement video coding

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Region-based video coding using a geometric motion compensation

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JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION 2000年第3期11卷 279-301页

作者： Huang, CS Lin, YY Sun, MT Natl Cent Univ Dept Elect Engn Chungli 32054 Taiwan Univ Washington Dept Elect Engn Seattle WA 98195 USA

A new region-based video coding technique, which combines region segmentation and geometric motion estimation, is proposed in this paper. The region segmentation algorithm based on both the histogram concavities and the probabilistic relaxation is applied to extract the significant regions. The merging of regions in the segmentation depends on the attributes of the regions, besides the motion vectors. A new approach based on the geometric features of objects and the scalable translation invariant rotation-to-shifting (STIRS) signatures is applied to the motion estimation of the global regions. Vector quantization (VQ) techniques are employed to solve the problems due to nonrigid object motions. With these techniques, the critical regions can be extracted with good performance and relatively low complexity. Furthermore, an uncovered/overlapped motion compensation method is presented. The integral algorithm is compared to Yokoyama's algorithm (Yokoyama et al., 1995, IEEE Trans. Circuit Systems video Technol. 5, 500-507). Our simulations show improved performance, in terms of both SNR improvement and reduction of computational requirements. For example, we achieve about 15% reduction of computational time and about 0.8 dB improvement in SNR for the "Miss America sequence." The frame-to-frame SNR variation is also much smaller, which implies that the visual quality between frames is also very stable. (C) 2000 Academic Press.

关键词： video coding region segmentation computational time Motion compensation motion vector Vector quantization motion estimation

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Segmentation-based motion-compensated video coding using morphological filters

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 1997年第3期7卷 549-555页

作者： Wang, DM Labit, C Ronsin, J INST NATL RECH INFORMAT & AUTOMAT IRISA F-35042 RENNES FRANCE INST NATL SCI APPL LAB AUTOMAT F-35043 RENNES FRANCE

The number of regions and length of contour are two basic constraints in segmentation-based motion-compensated video coding, This paper presents a coding scheme which focuses on region number reduction, contour coding, and displaced frame difference (DFD) compression. One of the important features of the proposed scheme is a spatiotemporal simplification algorithm based on morphological filters, with which an image can be segmented into a small number of regions, Another important feature of the scheme is a segmentation map sampling technique which reduces contour length by about 50% with a very small reconstruction error. Experimental results show that, using the proposed scheme, a high compression ratio can be achieved with a small coding error for video sequences such as Miss America and Foreman.

关键词： image segmentation image simplification morphological filter motion compensation video coding

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Direct Intermode Selection for H.264 video coding Using Phase Correlation

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2011年第2期20卷 461-473页

作者： Paul, Manoranjan Lin, Weisi Lau, Chiew Tong Lee, Bu-sung Nanyang Technol Univ Sch Comp Engn Nanyang Singapore

The H.264 video coding standard exhibits higher performance compared to the other existing standards such as H. 263, MPEG-X. This improved performance is achieved mainly due to the multiple-mode motion estimation and compensation. Recent research tried to reduce the computational time using the predictive motion estimation, early zero motion vector detection, fast motion estimation, and fast mode decision, etc. These approaches reduce the computational time substantially, at the expense of degrading image quality and/or increase bitrates to a certain extent. In this paper, we use phase correlation to capture the motion information between the current and reference blocks and then devise an algorithm for direct motion estimation mode prediction, without excessive motion estimation. A bigger amount of computational time is reduced by the direct mode decision and exploitation of available motion vector information from phase correlation. The experimental results show that the proposed scheme outperforms the existing relevant fast algorithms, in terms of both operating efficiency and video coding quality. To be more specific, 82 similar to 92% of encoding time is saved compared to the exhaustive mode selection (against 58 similar to 74% in the relevant state-of-the-art), and this is achieved without jeopardizing image quality (in fact, there is some improvement over the exhaustive mode selection at mid to high bit rates) and for a wide range of videos and bitrates (another advantages over the relevant state-of-the-art).

关键词： H264 mode selection motion compensation motion estimation phase correlation video coding

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Fast mode decision algorithm for intraprediction in H.264/AVC video coding

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2005年第7期15卷 813-822页

作者： Pan, F Lin, X Rahardja, S Lim, KP Li, ZG Wu, DJ Wu, S Inst Infocomm Res Singapore 119613 Singapore

The H.264/AVC video coding standard aims to enable significantly improved compression performance compared to all existing video coding standards. In order to achieve this, a robust rate-distortion optimization (RDO) technique is employed to select the best coding mode and reference frame for each macroblock. As a result, the complexity and computation load increase drastically. This paper presents a fast mode decision algorithm for H.264/AVC intraprediction based on local edge information. Prior to intraprediction, an edge map is created and a local edge direction histogram is then established for each subblock. Based on the distribution of the edge direction histogram, only a small part of intraprediction modes are chosen for RDO calculation. Experimental results show that the fast intraprediction mode decision scheme increases the speed of intracoding significantly with negligible loss of peak signal-to-noise ratio.

关键词： AVC H.264 intraprediction JVT MPEG video coding

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