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Frequency sensitivity for video compression

OPTICAL ENGINEERING 2014年第3期53卷 1-14页

作者： Seo, Guiwon Lee, Jonghwa Lee, Chulhee Yonsei Univ Dept Elect & Elect Engn Seoul 120749 South Korea

We investigate the frequency sensitivity of the human visual system, which reacts differently at different frequencies in video coding. Based on this observation, we used different quantization steps for different frequency components in order to explore the possibility of improving coding efficiency while maintaining perceptual video quality. In other words, small quantization steps were used for sensitive frequency components while large quantization steps were used for less sensitive frequency components. We performed subjective testing to examine the perceptual video quality of video sequences encoded by the proposed method. The experimental results showed that a reduction in bitrate is possible without causing a decrease in perceptual video quality. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

关键词： video compression frequency sensitivity HVS coding efficiency perceptual video quality

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Perceptual Video Compression: A Survey

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IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING 2012年第6期6卷 684-697页

作者： Lee, Jong-Seok Ebrahimi, Touradj Yonsei Univ Sch Integrated Technol Inchon 406840 South Korea Ecole Polytech Fed Lausanne Inst Elect Engn Multimedia Signal Proc Grp CH-1015 Lausanne Switzerland

With the advances in understanding perceptual properties of the human visual system and constructing their computational models, efforts toward incorporating human perceptual mechanisms in video compression to achieve maximal perceptual quality have received great attention. This paper thoroughly reviews the recent advances of perceptual video compression mainly in terms of the three major components, namely, perceptual model definition, implementation of coding, and performance evaluation. Furthermore, open research issues and challenges are discussed in order to provide perspectives for future research trends.

关键词： coding efficiency focus of attention human visual system perceptual video compression quality of experience (QoE) region of interest visual perception

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Block-Matching-Based Implementation of Affine Motion Estimation for HEVC

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2018年第4期E101D卷 1151-1158页

作者： Tsutake, Chihiro Yoshida, Toshiyuki Univ Fukui Grad Sch Engn Dept Informat Sci Fukui 9108507 Japan

Many of affine motion compensation techniques proposed thus far employ least-square-based techniques in estimating affine parameters, which requires a hardware structure different from conventional block-matching-based one. This paper proposes a new affine motion estimation/compensation framework friendly to block-matching-based parameter estimation, and applies it to an HEVC encoder to demonstrate its coding efficiency and computation cost. To avoid a nest of search loops, a new affine motion model is first introduced by decomposing the conventional 4-parameter affine model into two 3-parameter ones. Then, a block-matching-based fast parameter estimation technique is proposed for the models. The experimental results given in this paper show that our approach is advantageous over conventional techniques.

关键词： H.265/HEVC affine motion estimation/compensation block matching coding efficiency computation cost

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Efficient Scalable UHD/360-Video coding by Exploiting Common Information With Cuboid-Based Partitioning

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2022年第6期32卷 3961-3977页

作者： Afsana, Fariha Paul, Manoranjan Murshed, Manzur Taubman, David Charles Sturt Univ Sch Comp & Math Bathurst NSW 2795 Australia Federat Univ Australia Fac Sci & Technol Ballarat Vic 3350 Australia Univ New South Wales Sch Elect Engn & Telecommun Sydney NSW 2052 Australia

The scalable extension of High efficiency Video coding, SHVC can code Ultra High-Definition (UHD) video, including 360-degree video for various devices to serve a single bitstream with different display resolutions and qualities. To improve the SHVC compression efficiency, this paper proposes a novel intra and inter-frame coding scheme by first separating the common/visually important information and then applying cuboid-based variable size block partitioning and coding process for the common/visually important information in the base layer. In cuboid-based partitioning a video frame is partitioned into arbitrary shaped rectangular regions, known as cuboids, based on the distribution of relatively homogeneous pixel values. As the cuboid adopts a variable block partitioning based on the homogeneity of the data value, the partitioned blocks have better alignment with the object boundary. Moreover, in the cuboid coding process, only the partitioning tree information and a single value for each block need to be coded which takes lower number of bits and computational time compared to the traditional SHVC base layer. To verify the performance of the proposed method we embedded the proposed scheme as a base layer into the standard SHVC reference software and used several popular UHD/360-degree videos. The experimental results indicate that the proposed scalable coding strategy achieves an average of 14.04% BD-Rate reduction and 0.61 dB BD-PSNR gain for UHD/360-video compared to the operation points provided by an SHVC conforming encoder.

关键词： Encoding Video coding Scalability Streaming media Redundancy Decoding Bit rate Scalable coding SHVC UHD 360-degree video coding cuboid partitioning coding efficiency

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Adaptive Single-Multiple Prediction for H.264/AVC Intra coding

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2010年第4期20卷 610-615页

作者： Kim, Dae-Yeon Han, Ki-Hun Lee, Yung-Lyul Sejong Univ Dept Comp Engn Seoul 143747 South Korea

Intra coding is used for reducing the spatial redundancy in video coding. H.264/MPEG-4 advanced video coding (AVC) supports several types of macroblock (MB) mode for Intra coding. Also, each of these MB modes has several directional prediction modes, which significantly improve the Intra coding efficiency, but also increase the encoding complexity. In this letter, we present an adaptive single-multiple prediction method for H.264/AVC Intra coding that not only improves the coding efficiency, but also reduces the encoding complexity. The proposed method adaptively skips the prediction mode bits, so that the encoder complexity can be reduced. The experimental results show that the proposed method achieves a bit-rate reduction of 3.58% and encoding time reduction of 42.4%.

关键词： coding efficiency H.264/AVC Intra coding rate-distortion optimization (RDO) spatial prediction

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Adaptive weighted non-parametric background model for efficient video coding

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NEUROCOMPUTING 2017年 226卷 35-45页

作者： Chakraborty, Subrata Paul, Manoranjan Murshed, Manzur Ali, Mortuza Univ Southern Queensland Sch Management & Enterprise Sinnathamby BlvdPOB 4196 Springfield Cent Qld 4300 Australia Charles Sturt Univ Sch Comp & Math Panorama Ave Bathurst NSW 2795 Australia Federat Univ Sch Informat Technol Northways RdPOB 3191 Gippsland Mail Ctr Vic 3841 Australia

Dynamic background frame based video coding using mixture of Gaussian (MoG) based background modelling has achieved better rate distortion performance compared to the H.264 standard. However, they suffer from high computation time, low coding efficiency for dynamic videos, and prior knowledge requirement of video content. In this paper, we introduce the application of the non-parametric (NP) background modelling approach for video coding domain. We present a novel background modelling technique, called weighted non parametric (WNP) which balances the historical trend and the recent value of the pixel intensities adaptively based on the content and characteristics of any particular video. WNP is successfully embedded into the latest HEVC video coding standard for better rate-distortion performance. Moreover, a novel scene adaptive non parametric (SANP) technique is also developed to handle video sequences with high dynamic background. Being non-parametric, the proposed techniques naturally exhibit superior performance in dynamic background modelling without a priori knowledge of video data distribution.

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

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Power-efficient burst-mode RF transmitter based on reference-adaptive multilevel pulse-width modulation

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INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS 2018年第3期46卷 427-452页

作者： Arian, Amir Jannesari, Abumoslem Tarbiat Modares Univ Fac Elect & Comp Engn Tehran Iran

Burst-mode operation of power amplifier (PA) based on multilevel pulse-width modulation (MPWM) has been frequently discussed as a potential solution to achieve higher efficiency in radio frequency (RF) transmitters. In this paper, a novel multilevel PWM modulator is proposed that utilizes adaptive triangular reference waveforms. As compared with conventional MPWM modulators, the proposed architecture provides significant wider design space such that the efficiency of system can be effectively optimized. A general transmitter architecture based on the proposed concept is analyzed in terms of power efficiency. efficiency optimization procedures are presented according to input magnitude statistics. Based on the proposed modulator, an optimized 2.4-GHz RF transmitter is designed in a 0.18-m complementary metal-oxide-semiconductor (CMOS) process. The circuit-level simulations show that it delivers 25.8-dBm peak output power with 46.1% peak efficiency. For a 20-MHz worldwide interoperability for microwave access (WiMAX) signal with 8.5-dB peak-to-average-power ratio (PAPR), this transmitter achieves 28.8% (average) efficiency at 17.3-dBm (average) output power with an error vector magnitude (EVM) of 2.97% rms.

关键词： burst-mode operation coding efficiency efficiency optimization power amplifier (PA) power-efficient radio frequency (RF) transmitter pulse-width modulation (PWM)

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Rate-distortion/complexity analysis of HEVC, VVC and AV1 video codecs

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MULTIMEDIA TOOLS AND APPLICATIONS 2020年第39-40期79卷 29621-29638页

作者： Garcia-Lucas, D. Cebrian-Marquez, G. Cuenca, P. Univ Castilla La Mancha High Performance Networks & Architectures Grp Albacete Spain Univ Politecn Madrid Escuela Tecn Super Ingenieros Informat Madrid Spain

With the advent of smartphones and tablets, the amount of online video traffic has increased enormously. This, together with the growing popularity of high-definition video, motivated the development of the High efficiency Video coding (HEVC) standard, released in 2013, with the aim of achieving a 50% bitrate reduction with respect to its predecessor, namely H.264/MPEG-4 Advanced Video coding (AVC). However, new contents with greater resolutions and requirements arise every day, making it necessary to reduce the bitrate to a further extent. In this regard, the efforts to become the leading video codec in the market resulted in two main contenders: the Joint Video Experts Team (JVET), which leads the development of the Versatile Video coding (VVC) standard, and the Alliance for Open Media (AOMedia), which spearheads the AOMedia Video 1 (AV1) project. In this context, this paper presents a rate-distortion/complexity analysis of HEVC, VVC and AV1 main video codecs using objective measures of assessment in order to analyze their real capabilities. The analysis, which was done using well-defined test conditions, reveals that VVC considerably outperforms both HEVC and AV1 in terms of coding efficiency.

关键词： HEVC VVC AV1 Computational time coding efficiency

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An Efficient Video coding System With an Adaptive Overfitted Multi-Scale Attention Network

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IEEE ACCESS 2021年 9卷 64022-64032页

作者： He, Gang Wu, Chang Xu, Li Li, Lei Xu, Ziyao Xie, Weiying Li, Yunsong Xidian Univ Sch Telecommun Engn State Key Lab Integrated Serv Networks Xian 710071 Peoples R China

We herein propose an efficient video coding system (EVCS) consists of a conventional codec and an adaptive overfitted multi-scale attention network (MSAN) to improve coding efficiency. At the encoder side, the MSAN adjusts the network size adaptively and is trained in an overfitting way for a group of frames. Using only the current encoding video stream as a training set, the MSAN can easily obtain powerful restoration capability. After training, the learned parameters of the MSAN are transmitted to the decoder as part of the encoded bitstream. At the decoder side, the MSAN loaded with the transmitted parameters can restore the reconstructed frames very meticulously. Compared with the high efficiency video coding (HEVC) standard, the EVCS can achieve 12.141% Bjontegaard-Delta bitrate reduction, which outperforms existing deep learning based compressed video restoration works with less computation complexity. Moreover, the MSAN is an additional part of the conventional codec without any structure change, thereby rendering it compatible with the existing coding systems.

关键词： Decoding Video coding Training Image restoration Feature extraction Neural networks Image coding Video compression overfitting deep neural network coding efficiency quality improvement

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Artistic representations: Clues to efficient coding in human vision

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VISUAL NEUROSCIENCE 2011年第4期28卷 371-379页

作者： Graham, Daniel J. Meng, Ming Univ Vienna Dept Psychol Basic Res A-1010 Vienna Austria Dartmouth Coll Dept Psychol & Brain Sci Hanover NH 03755 USA

In what ways is mammalian vision-and in particular, human vision-efficiently adapted to its ecology? We suggest that human visual artwork, which is made for the human eye, holds clues that could help answer this question. Paintings are readily perceived as representations of natural objects and scenes, yet statistical relationships between natural images and paintings are nontrivial. Although spatial frequency content is generally similar for art and natural images, paintings cannot reproduce the dynamic range of luminance in scenes. Through a variety of image manipulations designed to alter image intensity distributions and spatial contrast, we here investigate the notion that artists' representational strategies can efficiently capture salient features of natural images, and in particular, of faces. We report that humans perform near flawless discrimination of faces and nonfaces in both paintings and natural images, even for stimulus presentation durations of 12 ms. In addition, contrast negation and up-down inversion have minimal to no effect on performance for both image types, whereas 1/f noise addition significantly affects discrimination performance for art more than for natural images. Together, these results suggest artists create representations that are highly efficient for transmitting perceptual information to the human brain.

关键词： coding efficiency Art perception Face detection Natural scene statistics Cortex

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