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High-Order Integer Cosine Transform: Construction Method and Fast Algorithms for High-Resolution Image and Video coding

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CYBERNETICS AND SYSTEMS ANALYSIS 2017年第4期53卷 615-626页

作者： Hnativ, L. O. Natl Acad Sci Ukraine VM Glushkov Inst Cybernet Kiev Ukraine

Matrix method of constructing one-norm high-order integer cosine transform is proposed. The one-norm order-32 integer transform is constructed and its fast algorithms of low computing complexity are developed. Its computing complexity is 3.24 times less than that in the well-known algorithms and 15.6 times less than in standard H.265 and requires integer operations only. This transform is not only very close to the discrete cosine transform but also has excellent coding performance.

关键词： discrete cosine transform integer cosine transform scaled transform factorization fast transform coding gain computing complexity compression ratio video coding H. 264 H. 265 AVS

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Optimized linear phase filter banks for wavelet image coding

Optimized linear phase filter banks for wavelet image coding

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Visual Communications and Image Processing 1998 Conference

作者： Yang, XG Ramchandran, K Univ Illinois Beckman Inst Urbana IL 61801 USA

ISBN: (纸本)0819427497

In this paper, we address the issue of designing a two-channel linear phase biorthogonal filter bank that maximizes the two most desired properties for Che wavelet transform in image coding applications, namely, orthogonality and energy compaction. Proper cost functions are formulated for these two criteria and an efficient signal-adaptive optimization algorithm is proposed. Our algorithm is motivated by a number of interesting properties of the correlation matrix of typical image signals, and uses Lifting operations to efficiently represent the degrees of freedom subject to perfect reconstruction conditions. In addition, it offers a successive tradeoff between our two optimization goals. Experimental results on re popular Daubechies 9-7 and 10-18 filter banks reveal that considerable improvements in terms of both orthogonality and energy compaction can be achieved through the proposed optimization technique.

关键词： subband filters coding gain perfect reconstruction linear phase biorthogonality

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MULTI-RELAY COOPERATIVE NB-LDPC coding WITH NON-BINARY REPETITION CODES OVER BLOCK-FADING CHANNELS

MULTI-RELAY COOPERATIVE NB-LDPC CODING WITH NON-BINARY REPET...

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20th European Signal Processing Conference (EUSIPCO)

作者： Savin, Valentin Declercq, David Pfletschinger, Stephan CEA LETI MINATEC Campus F-38054 Grenoble France UCP CNRS UMR 8051 ETIS ENSEA F-95000 Cergy Pontoise France Cent Tecnol Telecom Catalunya Castelldefels 08860 Spain

ISBN: (纸本)9781467310680

In this paper, we propose a cooperative coding scheme to communicate efficiently over multiple-relay fading channels. The particularity of our approach is to rely on non-binary LDPC codes at the source, coupled with non-binary repetition codes at the relays. A simple joint decoding strategy is used at the receiver end, so that the decoding complexity is not increased compared to a system without relays, while preserving the coding gain brought by re-encoding the signal at the relays. We show by simulations that the proposed scheme allows maintaining a constant gap to the outage probability of the cooperative system, irrespective of the number of relays.

关键词： relay low density parity check codes Fading channels Repetition coding gain Codes DEcoding Simple joint

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On the Need for Buffer Optimization Strategies for Inter-Session Network coding

On the Need for Buffer Optimization Strategies for Inter-Ses...

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IEEE International Conference on Communications (ICC)

作者： Paramanathan, Achuthan Lucani, Daniel E. Fitzek, Frank H. P. Aalborg Univ Dept Elect Syst Aalborg Denmark

ISBN: (纸本)9781479946402

During the past decades inter-session network coding for wireless network has been proven to be an effective tool being capable of providing a many-folded gain in terms of throughput. In order to utilize the full potential of inter-session network coding, any coding node needs to operate in an ideal wireless environment that provides equal flow of incoming packets. However, such an ideal wireless environment is seldom seen in a real world scenario. In this work, we address one of the issue that may arise in a non-ideal wireless environment, namely asynchronous packet arrival at the relay leading to an inefficient coding gain. To overcome this, we present a buffer enhancement structure at the coding node that guarantees an equal packet distribution of the codable flows. This structure is implemented on our test platform and using it, we performed a real-life measurement. Our measurement results show that by ensuring an equal packet distribution at the relay yields an improvement in terms of system throughput in compare to an unequally distributed packet buffer structure.

关键词： Network coding relay Packet coding gain Throughput full potential wireless Wireless networks measurement result Packet Buffer Equal

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Parametrization construction of biorthogonal wavelet filter banks for image coding

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Signal, Image and Video Processing 2007年第1期1卷 63-76页

作者： Liu, Zaide Zheng, Nanning Institute of Artificial Intelligence and Robotics Xi'an Jiaotong University Xi'an 710049 China Department of Computer Science and Engineering Changshu Institute of Technology Changshu 215500 China

We construct popular biorthogonal wavelet filter banks (BWFBs) having the linear phase and arbitrary multiplicity of vanishing moments (VMs). A novel parametrization construction technique, which is based on the theory of Diophantine equation, is presented and explicit one-parameter expressions of the BWFBs are derived. Using the expressions, any one-parameter family of BWFBs with different VMs can be constructed, and ten families, i.e., 5/7, 6/6, 9/7, 6/10, 5/11, 10/6, 13/7, 6/14, 17/11, and 10/18 families, are constructed here. The free parameter can be used to optimize the resulting BWFBs with respect to other criteria. In particular, in each family, three specific BWFBs with attractive features are obtained by adjusting the free parameter: the first has optimum coding gain and rational coefficients;the second which also has rational coefficients is very close to a quadrature mirror filter (QMF) bank;and the third which has binary coefficients can realize a multiplication-free discrete wavelet transform. In addition, four BWFBs are systematically verified to exhibit performance competitive to several state-of-the-art BWFBs for image compression, and yet require lower computational costs. © 2007 Springer-Verlag London Limited.

关键词： Biorthogonal wavelets coding gain Compression performance Computational complexity Diophantine equation Discrete wavelet transform (DWT) Filter bank

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Improving coding efficiency in grid-based hybrid video coding schemes

Improving coding efficiency in grid-based hybrid video codin...

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IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Heising, G Heinrich Hertz Inst Nachrichtentech Berlin GmbH Image Proc Dept D-10587 Berlin Germany

ISBN: (纸本)0780374029

In the past many grid-based video coding schemes using image warping prediction have been proposed. The advantage of grid-based motion compensation is its ability to model nontranslational motion. Disadvantages are the interdependency of motion vectors which require more complex motion estimation strategies and its restricted ability to model motion boundaries. In this paper different solutions to cope with the latter deficiency are presented and compared with respect to coding efficiency, In particular, three adaptive modes for handling motion discontinuities and a block-adaptive loop filtering are presented. It is shown that these are key components for achieving a high coding gain in grid-based hybrid coding. Introducing these features into a wavelet-based video coder leads to a coding gain of up to 2,5 dB compared to ITU H263+ and MPEG-4.

关键词： video coding transform coding motion compensation motion estimation adaptive filters coding efficiency grid-based video coding hybrid video coding image warping prediction motion compensation motion estimation block-adaptive filtering loop filtering wavelet-based coder coding gain ITU H.263+ MPEG-4

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Research on a TCM-based Transmission Approach for EM-MWD by Combining Phase Modulation and Convolutional coding

Research on a TCM-based Transmission Approach for EM-MWD by ...

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IEEE International Instrumentation and Measurement Technology Conference (I2MTC)

作者： Zhang, Cheng Dong, Haobin Ge, Jian Liu, Huan Wang, Jiahao Luo, Wang Yuan, Zhiwen Zhu, Jun Zhang, Haiyang China Univ Geosci Sch Automat Wuhan 430074 Hubei Peoples R China Hubei Key Lab Adv Control & Intelligent Automat Wuhan 430074 Hubei Peoples R China Sci & Technol Near Surface Detect Lab Wuxi 214035 Jiangsu Peoples R China China Univ Geosci Sch Mech Engn & Elect Informat Wuhan 430074 Hubei Peoples R China

ISBN: (纸本)9781538634608

In practical applications of electromagnetic measurement while drilling (EM-MWD) in the underground coal mine, the signal-to-noise ratio (SNR) of the receiver cannot always meet the requirements of reliable communication conditions due to the earth-attenuation, interfering signal from a well site, etc. Traditional digital communication systems use independent design coding and modulation techniques to improve system performance. The coding is mainly achieved by introducing redundant bits and the improvement of error performance is at the expense of information rate. Aimed to solve this problem, we use a coding technique based on trellis coded modulation (TCM) to maximize the minimum distance between modulated output sequences and achieve significant coding gain. Simulation and experiments show that the system can improve the anti noise performance of the system by obtaining a coding gain without reducing the transmission rate. Compared to the uncoded quadrature phase shift keying (QPSK), TCM can achieve a coding gain of at least 3 dB under the same transmitting rate. At that time, as the number of TCM system states or trace back depth increases, the coding gain is further enhanced. The TCM code modulation method can be used in an EM-MWD system to improve the system performance.

关键词： EM-MWD Convolutional coding coding gain Trellis coded modulation

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A Practical Method for BEP Estimation of Convolutional coding in Impulse Noise Environments

A Practical Method for BEP Estimation of Convolutional Codin...

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IEEE Military Communications Conference (MILCOM)

作者： Eliardsson, Patrik Axell, Erik Komulainen, Arwid Wiklundh, Kia Tengstrand, Sara Orn Swedish Def Res Agcy Stockholm Sweden Qamcom Res & Technol Linkoping Sweden Scania CV AB Sodertalje Sweden

ISBN: (纸本)9781728142807

Forward error correction is a means to achieve robust communications. Knowing the performance of the error correcting code under operating circumstances is crucial in making a robust and cost-efficient design choice. Performance of error correcting codes are usually attained under the assumption of additive white Gaussian noise (AWGN). Such performance estimates can be orders of magnitude from the truth in impulse noise environments, that are common in military, automotive and industrial environments with lots of emitters and electronic equipment co-located closely together. A method previously proposed to model the impact of impulse noise, without the use of error correcting coding, is the impulsiveness correction factor (ICF), which can easily he measured. The main contribution of this work is to propose a practical method, using the ICE, to approximate the communication performance in impulse noise channels for a system using convolutional coding. Performance is evaluated in terms of bit error probability (BEP) at a given signalto-noise ratio (SNR), or analogously the required SNR to achieve a given BEP. The proposed method is practically useful for a wide range of interference types, and is derived numerically since the problem is analytically intractable. The proposed method uses the ICF of the uncoded system, code performance estimates for AWGN, and knowledge of the code parameters.

关键词： Impulse noise coding gain

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EVALUATION OF TRANSFORM PERFORMANCE WHEN USING SHAPE-ADAPTIVE PARTITIONING IN VIDEO coding

EVALUATION OF TRANSFORM PERFORMANCE WHEN USING SHAPE-ADAPTIV...

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Picture coding Symposium 2009

作者： Vermeirsch, Kenneth De Cock, Jan Notebaert, Stijn Lambert, Peter Van de Walle, Rik Univ Ghent IBBT Dept Elect & Informat Syst Multimedia Lab B-9050 Ghent Belgium

ISBN: (纸本)9781424445936

When combining non-rectangular (shape-adaptive) partitioning of inter pictures with a rectangular block transform, some of the transforms will be applied to a residual signal which originates from two different predictions. This is a condition that is never encountered in any of the existing video coding standards, and the impact of this on the performance of the transforrn coder has not been investigated. In this paper we investigate the effect of these mixed-signal blocks on the coding gain for various transforms, and we compare these against the optimal KLT gain. We find that, despite the transformed residual block being composed of two parts that were predicted from different areas of the reference picture, correlation within mixed blocks is very similar to that of normal blocks. The DCT is only marginally suboptimal w.r.t. KLT. KLT has practical issues that will reduce its coding gain or increase the signaling overhead: transform bases need to be quantized and transmitted, or a number of fixed bases needs to be chosen offline. Therefore we recommend DCT be used for all types of blocks.

关键词： Partitioning transformation coding gain shape-adaptive correlation DCT KLT

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Closed-Loop Extended Orthogonal Space Frequency Block coding Techniques for OFDM Based Broadband Wireless Access Systems

Closed-Loop Extended Orthogonal Space Frequency Block Coding...

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5th International Conference on Broadband Communications Networks and Systems

作者： Eltayeb, N. M. Kassim, S. K. Chambers, J. A. Univ Loughborough Dept Elect & Elect Engn Adv Signal Proc Grp Loughborough LE11 3TU Leics England

ISBN: (纸本)9781424423910

A simple extended orthogonal space-frequency coded multiple input single output (MISO) orthogonal frequency division multiplexing (OFDM) transmitter diversity technique for wireless communications over frequency selective fading channels is presented. The proposed technique utilizes OFDM to transform frequency selective fading channels into multiple flat fading sub-channels on which space-frequency coding is applied. A four-branch transmitter diversity system is implemented without bandwidth expansion and with only one receive antenna. The associated simulations verify that the four-branch transmitter diversity scheme achieves a significant improvement in average bit-error rate (BER) performance. The proposed scheme also outperforms the previously reported scheme due to Yu, Keroueden, and Yuan with only single phase feedback, and that improvement is retained with quantized feedback. Since the angle feedback is on a per tone basis, the feedback information would be too large for any practical OFDM system. However, we adopt a method which exploits the correlation among the feedback terms for the subcarriers, i.e. a group based quantization technique to reduce the feedback overhead significantly, rendering this scheme attractive to broadband wireless access systems. The performance improvement of convolutionally concatenated space-frequency block coding (CCSBC) schemes is also investigated.

关键词： Closed-loop (EO-SFBCs) Phase rotation array gain diversity gain coding gain

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