SP(Synchronization-Predictive) frame coding, which enables high efficiency of switching between two video bitstreams with different qualities, is supported by H.264/AVC. And FGS(Finc-Granular-Scalability) coding is su...
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Synchronization-predictive (SP) frame, which enables high efficiency of switching between two bitstreams with different qualities, is supported by H. 264/AVC. And fine-granular-scalability (FGS) video coding is suppor...
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Synchronization-predictive (SP) frame, which enables high efficiency of switching between two bitstreams with different qualities, is supported by H. 264/AVC. And fine-granular-scalability (FGS) video coding is supported by MPEG-4. The combination of the two tools was proposed to adapt high bandwidth variations of internet or wireless networks and low bandwidth variations flexibly. The experimental results show that the proposed system outperforms FGS by 0.47 dB and the H. 264/AVC-based stream switching (SS) approach by 0.23 dB on average.
The H.264/AVC standard can achieve higher compression efficiency at the expense of more computational complexity than previous standards. In inter pictures, a macroblock (MB) has 7 kinds of inter modes with different ...
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The H.264/AVC standard can achieve higher compression efficiency at the expense of more computational complexity than previous standards. In inter pictures, a macroblock (MB) has 7 kinds of inter modes with different block sizes and two kinds of intra modes with 4 × 4 and 16 × 16 sizes. The reference software performs a complex full search to determine the best mode, which adds the highest computational burden. In this paper, the fast mode decision algorithm is proposed that classifies all modes by both homogeneity and space-time correlation of MB. So computational complexity can be reduced greatly because just only part of modes would be chosen to compare with each other. The experiment results show that it can save about 35% of encoding time while maintaining similar visual quality.
Anisotropic conductive films (ACFs) are composed of an adhesive polymer matrix and fine conductive fillers using metallic particle or metal-coated polymer balls. Flip chip interconnection using ACF is being widely use...
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Anisotropic conductive films (ACFs) are composed of an adhesive polymer matrix and fine conductive fillers using metallic particle or metal-coated polymer balls. Flip chip interconnection using ACF is being widely used in the electronic packaging. In this paper, two-dimensional nonlinear finite element analysis model was built to simulate effects of bumps' metallization on the stress and strain distributions of ACF interconnections for flip-chip-on-flex (COF) applications. The simulation results show that the bump metallization has big influence on the stress and strain. Under the thermal mechanical simulation, the stress is mainly relied on the Young's modulus of the bump while the strain is mainly depended on the CTE of the bump. In some kinds of bump/pad metallization, such as gold, nickel and copper, the copper has smaller stress, only bigger than gold, and minimum strain. If both chip bump and substrate bump fabricated by same copper, the galvanic corrosion, which occurs between two different metals and the main cause attributed to the shift of the contact resistance of ACF, does not exist. Regarding the cost and reliability synchronously, the copper may be the better substitute of gold as bump material in flip chip using ACF
With the development of broadband wireless networks, high efficiency of wireless video transmission has been received increasingly greater attentions than before. One should settle the problems of high-compression eff...
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With the development of broadband wireless networks, high efficiency of wireless video transmission has been received increasingly greater attentions than before. One should settle the problems of high-compression efficiency and that of adaptation to the random variation of transmission bandwidth, as well as a network friendly design, in wireless environments. SP (Synchronization-Predictive) frame, which enables high efficiency of switching between two or more bitstreams with different qualities, is supported by H.264/AVC extended profile suitable for mobile services. On the other hand, FGS (fine-granular-scalability), which can always adapt to the network bandwidth varying but with some sacrifice of coding efficiency, is supported by MPEG-4. This paper proposes a solution for combination these two tools with each other so as to accommodate high bandwidth variations of wireless networks and low bandwidth variations flexibly for transmitted streams. Moreover, it also improves the efficiency of video streaming. Experimental results show that our proposed system outperforms FGS by 0.76 dB and the H.264/AVC-based video stream switching approach by 0.51 dB on average under 3GPP/3GPP2 wireless common test conditions
With the increasingly extensive applications for the new emerging video coding standard, H.264/AVC, it becomes more and more important that we transport H.264/AVC video over MPEG-2 system by exploiting all the existin...
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With the increasingly extensive applications for the new emerging video coding standard, H.264/AVC, it becomes more and more important that we transport H.264/AVC video over MPEG-2 system by exploiting all the existing large amount of the infrastructure of MPEG-2 systems. In this paper, we propose two solutions for it. The key technologies are as follows: firstly we use an H.264/AVC video as an elementary stream of an MPEG-2 system and multiplex it into a TS (transport stream), then extend the T-STD (transport stream-system target decoder) of MPEG-2 standard, so as to transport MPEG-2 TS through Internet and decode it in the client. Ordinarily, the decoded elementary stream should come from a container (a system layer encapsulation including a compression layer), such as AVI. However, we take MPEG-2 TS as a container herein. We encapsulate the H.264/AVC elementary stream into this container in the server, and extract the H.264/AVC video from it to be decoded and be represented. If we use the UDP (user datagram protocol) as a transport protocol, the streaming process will be a real-time one. The experiment result shows that we get a good result, with less than 5% frames whose PSNR<40 dB. We can even get a robust streaming by using the HTTP/TCP (hyper-text transport protocol/transport control protocol) as a transport protocol. All the streaming solutions that we proposed in this paper can also be used for mobile video.
Segmentation of moving object in a video sequence is one of the difficult problems in video processing. Moreover, multiple objects segmenting and extracting is more challenging task due to the complexity of multiple m...
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作者：
ZITZMAN, LHFALATKO, SMPAPACH, JLDr. Lewis H. Zitzman:is the group supervisor of the Advanced Systems Design Group
Fleet Systems Department The Johns Hopkins University Applied Physics Laboratory (JHU/APL). He has been employed at JHU/APL since 1972 performing applied research in computer science and in investigating and applying advanced computer technologies to Navy shipboard systems. He is currently chairman of Aegis Computer Architecture Data Bus and Fiber Optics Working Group from which many concepts for this paper were generated. Dr. Zitzman received his B.S. degree in physics from Brigham Young University in 1963 and his M.S. and Ph.D. degrees in physics from the University of Illinois in 1967 and 1972 respectively. Stephen M. Falatko:was a senior engineering analyst in the Combat Systems Engineering Department
Comptek Research Incorporated for the majority of this effort. He is currently employed at ManTech Services Corporation. During his eight-year career first at The Johns Hopkins University Applied Physics Laboratory and currently with ManTech Mr. Falatko's work has centered around the development of requirements and specifications for future Navy systems and the application of advanced technology to Navy command and control systems. He is a member of both the Computer Architecture Fiber Optics and Data Bus Working Group and the Aegis Fiber Optics Working Group. Mr. Falatko received his B.S. degree in aerospace engineering with high distinction from the University of Virginia in 1982 and his M.S. degree in applied physics from The Johns Hopkins University in 1985. Mr. Falatko is a member of Tau Beta Pi Sigma Gamma Tau the American Society of Naval Engineers and the U.S. Naval Institute. Janet L. Papach:is a section leader and senior engineering analyst in the Combat Systems Engineering Department
Comptek Research Incorporated. She has ten years' experience as an analyst supporting NavSea Spa War and the U.S. Department of State. She currently participates in working group efforts under Aegis Combat System Doctrin
This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis comp...
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This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis computer systems architecture, expanding that architecture while preserving, and adhering to, the Aegis fundamental principle of thorough systems engineering, dedicated to maintaining a well integrated, highly reliable, and easily operable combat system. The implementation of these proposed computer systems concepts in a coherent architecture would support the future battle force capable combat system and allow the expansion necessary to accommodate evolutionary changes in both the threat environment and the technology then available to effectively counter that threat. Changes to the current Aegis computer architecture must be carefully and effectively managed such that the fleet will retain its combat readiness capability at all times. This paper describes a possible transition approach for evolving the current Aegis computer architecture to a general architecture for the future. The proposed computer systems architecture concepts encompass the use of combinations of physically distributed, microprocessor-based computers, collocated with the equipment they support or embedded within the equipment itself. They draw heavily on widely used and available industry standards, including instruction set architectures (ISAs), backplane busses, microprocessors, computer programming languages and development environments, and local area networks (LANs). In this proposal, LANs, based on fiber optics, will provide the interconnection to support system expandability, redundancy, and higher data throughput rates. A system of cross connected LANs will support a high level of combat system integration, spanning the major warfare areas, and will facilitate the coordination and development of a coherent multi-warfare tactical picture supporting the future combatant command st
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