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HEVC encoding optimization Using Multicore CPUs and GPUs

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2015年第11期25卷 1830-1843页

作者： Xiao, Wei Li, Bin Xu, Jizheng Shi, Guangming Wu, Feng Xidian Univ Xian 710071 Peoples R China Microsoft Res Asia Beijing 100080 Peoples R China Univ Sci & Technol China Hefei 230026 Peoples R China

Although the High Efficiency Video Coding (HEVC) standard significantly improves the coding efficiency of video compression, it is unacceptable even in offline applications to spend several hours compressing 10 s of high-definition video. In this paper, we propose using a multicore central processing unit (CPU) and an off-the-shelf graphics processing unit (GPU) with 3072 streaming processors (SPs) for HEVC fast encoding, so that the speed optimization does not result in loss of coding efficiency. There are two key technical contributions in this paper. First, we propose an algorithm that is both parallel and fast for the GPU, which can utilize 3072 SPs in parallel to estimate the motion vector (MV) of every prediction unit (PU) in every combination of the coding unit (CU) and PU partitions. Furthermore, the proposed GPU algorithm can avoid coding efficiency loss caused by the lack of a MV predictor (MVP). Second, we propose a fast algorithm for the CPU, which can fully utilize the results from the GPU to significantly reduce the number of possible CU and PU partitions without any coding efficiency loss. Our experimental results show that compared with the reference software, we can encode high-resolution video that consumes 1.9% of the CPU time and 1.0% of the GPU time, with only a 1.4% rate increase.

关键词： encoding optimization graphics processing unit (GPU) H.264 High Efficiency Video Coding (HEVC) multicore central processing unit (CPU)

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SVC-based scalable multiple description video coding and optimization of encoding configuration

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2009年第9期24卷 691-701页

作者： Abanoz, T. Berkin Tekalp, A. Murat Koc Univ Coll Engn TR-34450 Istanbul Turkey

It is well known that multiple multicast trees can avoid single point of failures in peer-to-peer (P2P) streaming originating from a single source by providing path diversity. Multiple description video coding is well suited for serving video over multiple multicast trees, such that each description can be streamed over a different tree. In scalable multiple description coding (SMDC), each description is scalable coded (e.g., derived from a single scalable video coding (SVC)-compliant bitstream) so that descriptions can be efficiently adapted to the available rate of each link for effective congestion control. This paper proposes (i) new SMDC generation methods based on various combinations of video segments (GOPs or fames) coded at high and low rates (one or more layers) and (ii) a multiple-objective optimization (MOO) framework for selection of the best encoding configuration of the proposed SMDC from a set of candidates in order to achieve the best tradeoff between redundancy and reliability (measured by end-to-end rate-distortion performance over a range of extraction points for a set of packet loss probabilities), while maximizing the range of extraction points of each scalable description. The optimization is performed over selected SVC encoding parameters and MD generation alternatives that feature various levels of redundancy at a fixed total rate for all descriptions. The framework is generic to allow optimization over other SVC encoding variables and MD generation methods, or just over the SVC encoding variables without MD, if desired. Results of Monte-Carlo simulation of SMDC streaming with two descriptions over two paths with packet losses are provided to demonstrate performance of the proposed methods. (C) 2009 Elsevier B.V. All rights reserved.

关键词： Scalable video coding Multiple description video coding Peer-to-peer video Congestion control encoding optimization

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optimization OF encoding CONFIGURATION IN SCALABLE MULTIPLE DESCRIPTION CODING FOR RATE-ADAPTIVE P2P VIDEO MULTICASTING

OPTIMIZATION OF ENCODING CONFIGURATION IN SCALABLE MULTIPLE ...

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16th IEEE International Conference on Image Processing

作者： Abanoz, T. Berkin Tekalp, A. Murat Boston Univ Coll Engn Boston MA 02215 USA Kochi Univ Coll Engn TR-34450 Istanbul Turkey

ISBN: (纸本)9781424456536

It is well-known that in peer-to-peer (P2P) streaming from a single source, single point of failure can be avoided by multiple description coding over multiple multicast trees since it provides path diversity. In this scenario, we propose using scalable multiple description coding (SMDC), where each description is scalable so that all descriptions can be efficiently adapted to the available rate of each link for effective congestion control. We also propose a multiple objective optimization (MOO) framework for selection of the best encoding configuration for SMDC from a set of candidates, which will strike the best balance between minimizing average end-to-end rate-distortion performance of each description given a set of packet loss probabilities, while minimizing overall redundancy and maximizing the range of extraction points of each scalable description. The optimization variables are some SVC encoding parameters and MD generation alternatives that result in different levels of redundancy at a fixed total rate for all descriptions. The framework can be used for optimization over other SVC encoding variables and MD generation methods if desired. Results of Monte-Carlo simulation of SMDC streaming of videos demonstrate the performance of the proposed method.

关键词： Scalable video coding multiple description video coding congestion control peer-to-peer video encoding optimization

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1-bit encoding optimized transparent ultra-wideband microwave absorber

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MATERIALS RESEARCH BULLETIN 2024年 176卷

作者： Lai, Senfeng Luo, Jingyi Fu, Huiyuan Tan, Junxian Guangdong Polytech Normal Univ Coll Elect & Informat Guangzhou 510665 Peoples R China Southeast Univ State Key Lab Millimeter Waves Nanjing 210096 Peoples R China

This work is dedicated to designing high-performance microwave absorbers that meet the pressing needs for advanced stealth materials, which are controllable, ultra-thin, transparent, and ultra-wideband. Consequently, we propose two transparent ultra-wideband microwave absorbers based on 1-bit encoded optimization in this study. We analyze the absorption mechanisms of these two coded absorbers, emphasizing their complementary bandwidth properties. Among them, the Chinese character "Mi" structure encoded absorber achieves an absorption rate exceeding 90 % within the frequency range of 15.7 to 49.4 GHz, with a fractional bandwidth being only 0.07 times its upper cutoff wavelength. This absorber demonstrates remarkable stability under varying incident angles and maintains polarization insensitivity. It sustains an approximate 80 % absorption rate as the incident angle varies from 0 degrees-60 degrees. Finally, fabricated test samples exhibit absorption performance consistent with simulations across the 10-40 GHz frequency range, thereby validating the effectiveness of the proposed design.

关键词： encoding optimization Transparent Ultra-wideband Microwave absorber

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Comparison of gradient encoding schemes for diffusion-tensor MRI

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JOURNAL OF MAGNETIC RESONANCE IMAGING 2001年第5期13卷 769-780页

作者： Hasan, KM Parker, DL Alexander, AL Univ Utah Dept Phys Salt Lake City UT 84112 USA

The accuracy of single diffusion tensor MRI (DT-MRI) measurements depends upon the encoding scheme used. In this study, the diffusion tensor accuracy of several strategies for DT-MRI encoding are compared. The encoding strategies are based upon heuristic, numerically optimized, and regular polyhedra schemes. The criteria or numerical optimization include the minimum tensor variance (MV), minimum force (MF), minimum potential energy (ME), and minimum condition number. The regular polyhedra scheme includes variations of the icosahedron. Analytical comparisons and Monte Carlo simulations show that the icosahedron scheme is optimum for six encoding directions. The MV, AW, and ME solutions for six directions are functionally equivalent to the icosahedron scheme. Two commonly used heuristic DT-MRI encoding schemes with six directions, which are based upon the geometric landmarks of a cube (vertices, edge centers, and face centers), are found to be suboptimal. For more than six encoding directions, many methods are able to generate a set of equivalent optimum encoding directions including the regular polyhedra, and the ME, Aff and MV numerical optimization solutions. For seven directions, a previously described heuristic encoding scheme (tetrahedral plus x, y, z) was also found to be optimum. This study Indicates that there is no significant advantage to using more than six encoding directions as long as an optimum encoding is used for six directions. Future DT-MRI studies are necessary to validate these observations. (C) 2001 Wiley-Liss, Inc.

关键词： diffusion tensor icosahedron encoding optimization heuristic polyhedra numerically optimized polyhedra regular polyhedra

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ENHANCED CU PARTITIONING SEARCH METHOD FOR INTRA CODING IN HEVC

ENHANCED CU PARTITIONING SEARCH METHOD FOR INTRA CODING IN H...

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IEEE International Conference on Multimedia and Expo (ICME)

作者： Li, Yunchang Sun, Jun Peking Univ Wangxuan Inst Comp Sci Beijing Peoples R China

ISBN: (纸本)9781728113319

Most encoders in High Efficiency Video Coding (HEVC) standard determine the coding unit (CU) partitions in a depth-first full search manner. For intra coding, this method ignores the impact of partitioning on the subsequent blocks, which incurs less accurate prediction and worsens encoding efficiency performance. In this paper, we present an enhanced CU partitioning search method, where the various partitioning types are examined to effectively mitigate such impact. To reduce the additional complexity, we further refine the search candidates, early terminate the search process, and reuse encoding information. Experimental results show that compared with the unmodified HM software, the proposed method achieves a bit rate saving of 0.34% on average and 0.67% at most. Since our method doesn't modify the original definition of HEVC, the encoded bitstreams can be uncompressed by a standard HEVC decoder with no complexity increase.

关键词： CU partitioning encoding optimization HEVC intra coding

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An Efficient encoding Method for Video Compositing in HEVC 26th

An Efficient Encoding Method for Video Compositing in HEVC

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26th International Conference on MultiMedia Modeling (MMM)

作者： Li, Yunchang Huang, Zhijie Sun, Jun Peking Univ Wangxuan Inst Comp Technol Beijing Peoples R China

ISBN: (纸本)9783030377311;9783030377304

Video compositing for compressed HEVC streams is highly demanded in instant communication applications such as video chat. As a flexible scheme, pixel domain compositing involves the processes of completely decoding the streams, inserting the decoded video, and finally re-encoding the new composite video. The time consumption of the whole scheme comes almost entirely from the re-encoding process. In this paper, we propose an efficient encoding method to speedup the re-encoding process and improve encoding efficiency. The proposed method separately designs encoding for blocks inside the frame region covered by inserted video and blocks in non-inserted region, which overcomes numerous difficulties of utilizing information from the decoding process. Experimental results show that the proposed method achieves a PSNR increase of 0.33 dB, or a bit rate saving of 10.11% on average compared with normal encoding using unmodified HM software. Furthermore, the encoding speed is 7.04 times that of normal encoding method, equivalent to an average reduction of 85.8% in computational complexity.

关键词： Video compositing High Efficiency Video Coding (HEVC) encoding optimization Information reuse

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Deterministic Finite Automata Characterization and optimization for Scalable Pattern Matching

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ACM TRANSACTIONS ON ARCHITECTURE AND CODE optimization 2011年第1期8卷 4-4页

作者： Vespa, Lucas Weng, Ning So Illinois Univ Carbondale Dept Elect & Comp Engn Carbondale IL 62901 USA

Memory-based Deterministic Finite Automata (DFA) are ideal for pattern matching in network intrusion detection systems due to their deterministic performance and ease of update of new patterns, however severe DFA memory requirements make it impractical to implement thousands of patterns. This article aims to understand the basic relationship between DFA characteristics and memory requirements, and to design a practical memory-based pattern matching engine. We present a methodology that consists of theoretical DFA characterization, encoding optimization, and implementation architecture. Results show the validity of the characterization metrics, effectiveness of the encoding techniques, and efficiency of the memory-based pattern engines.

关键词： Design Security Pattern matching deterministic finite automata encoding optimization

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DeSP: a systematic DNA storage error simulation pipeline

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BMC BIOINFORMATICS 2022年第1期23卷 185-185页

作者： Yuan, Lekang Xie, Zhen Wang, Ye Wang, Xiaowo Tsinghua Univ Minist Educ Key Lab Bioinformat Beijing Peoples R China Tsinghua Univ Ctr Synthet & Syst Biol Beijing Peoples R China Tsinghua Univ Beijing Natl Res Ctr Informat Sci & Technol Beijing Peoples R China Tsinghua Univ Dept Automat Beijing Peoples R China Tsinghua Univ Tsinghua Berkeley Shenzhen Inst Shenzhen 518055 Peoples R China

Background: Using DNA as a storage medium is appealing due to the information density and longevity of DNA, especially in the era of data explosion. A significant challenge in the DNA data storage area is to deal with the noises introduced in the channel and control the trade-off between the redundancy of error correction codes and the information storage density. As running DNA data storage experiments in vitro is still expensive and time-consuming, a simulation model is needed to systematically optimize the redundancy to combat the channel's particular noise structure. Results: Here, we present DeSP, a systematic DNA storage error Simulation Pipeline, which simulates the errors generated from all DNA storage stages and systematically guides the optimization of encoding redundancy. It covers both the sequence lost and the within-sequence errors in the particular context of the data storage channel. With this model, we explained how errors are generated and passed through different stages to form final sequencing results, analyzed the influence of error rate and sampling depth to final error rates, and demonstrated how to systemically optimize redundancy design in silico with the simulation model. These error simulation results are consistent with the in vitro experiments. Conclusions: DeSP implemented in Python is freely available on Github (https://***/WangLabTHU/DeSP). It is a flexible framework for systematic error simulation in DNA storage and can be adapted to a wide range of experiment pipelines.

关键词： DeSP DNA storage Systematic error simulation encoding optimization Web application

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