Author: Russell Everett HenningPublisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 142
Book Description
Evaluation of Channel-optimized Vector Quantization for Coding Images Transmitted by Deep Space Probes
Author: Russell Everett HenningPublisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 142
Book Description
A Study of Vector Quantization for Noisy Channels
Author: Nariman FarvardinPublisher:
ISBN:
Category : Data compression (Telecommunication)
Languages : en
Pages : 35
Book Description
Channel Optimized Vector Quantization
Author: Hamidreza Ebrahimzadeh SaffarPublisher:
ISBN:
Category :
Languages : en
Pages : 234
Book Description
Joint source-channel coding (JSCC) has emerged to be a major field of research recently. Channel optimized vector quantization (COVQ) is a simple feasible JSCC scheme introduced for communication over practical channels. In this work, we propose an iterative design algorithm, referred to as the iterative maximum a posteriori (MAP) decoded (IMD) algorithm, to improve COVQ systems. Based on this algorithm, we design a COVQ based on symbol MAP hard-decision demodulation that exploits the non-uniformity of the quantization indices probability distribution. The IMD design algorithm consists of a loop which starts by designing a COVQ, obtaining the index source distribution, updating the discrete memoryless channel (DMC) according to the achieved index distribution, and redesigning the COVQ. This loop stops when the point-to-point distortion is minimized. We consider memoryless Gaussian and Gauss-Markov sources transmitted over binary phase-shift keying modulated additive white Gaussian noise (AWGN) and Rayleigh fading channels. Our scheme, which is shown to have less encoding complexity than conventional COVQ and less encoding complexity and storage requirements than soft-decision demodulated (SDD) COVQ systems, is also shown to provide a notable signal-to-distortion ratio (SDR) gain over the conventional COVQ designed for hard-decision demodulated channels while sometimes matching or exceeding the SDD COVQ performance, especially for higher quantization dimensions and/or rates. In addition to our main result, we also propose another iterative algorithm to design SDD COVQ based on the notion of the JSCC error exponent. This system is shown to have some gain over classical SDD COVQ both in terms of the SDR and the exponent itself.
Channel-Matched Hierarchical Table-Lookup Vector Quantization for Transmission of Video Over Wireless Channels
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 7
Book Description
The authors propose a channel-matched hierarchical table-lookup vector quantizer (CM-HTVQ) which provides some robustness against the channel noise. They use a finite-state channel to model slow fading channels and propose an adaptive coding scheme to transmit a source over wireless channels. The performance of CM-HTVQ is in general slightly inferior to that of channel-optimized vector quantizer (COVQ) (the performances coincide in some cases); however, the encoder complexity of CM-HTVQ is much less than the encoder complexity of COVQ.
Robust Video Coding Using Multiple Description Lattice Vector Quantization with Channel Optimization
Author: Joint source-channel coding using tree-strctured vector quantization for remote sensing images
Author: Publisher:
ISBN:
Category :
Languages : pt-BR
Pages :
Book Description
Este trabalho estuda o problema de compressão de imagens de sensoriamento remoto segundo a ótica da codificação conjunta fonte-canal. É analisado o desempenho de métodos baseados em quantização vetorial segundo o algoritmo LBG, principalmente o COVQ (Channel Optimized Vector Quantizer) bem como a quantização vetorial estruturada em árvore. Dentro desse contexto, são propostos 2 novos métodos para a resolução do problema: (1)Uma quantização vetorial estruturada em árvores que leva em conta a transmissão através de canais ruidosos, solução denominada COTSVQ (Channel-Design Tree Strutured Vecotr Quantizer), bem como (2) uma classe de métodos que se utiliza de códigos corretores de erro sobre a estrutura progressiva do TSVQ, de forma a proteger os dados de forma ativa durante a transmissão. Os dois métodos propostos podem ser combinados no mesmo compressor, de forma a originar uma classe ampla de compressores adaptados à transmissão por canais com ruído. São apresentados resultados que comparam os desempenhos dos métodos propostos com aqueles já existentes para uma análise de desempenho, na situação de transmissão via satélite de imagens captadas e comprimidas para uma taxa de 1,5bpp. Os resultados mostram que os métodos propostos são muito menos complexos que os já existentes, porém conseguindo atingir uma qualidade de imagem equivalente, ou, em alguns casos, superior.
Information and Management Engineering
Author: Min ZhuPublisher: Springer Science & Business Media
ISBN: 3642240968
Category : Computers
Languages : en
Pages : 581
Book Description
This six-volume-set (CCIS 231, 232, 233, 234, 235, 236) constitutes the refereed proceedings of the International Conference on Computing, Information and Control, ICCIC 2011, held in Wuhan, China, in September 2011. The papers are organized in two volumes on Innovative Computing and Information (CCIS 231 and 232), two volumes on Computing and Intelligent Systems (CCIS 233 and 234), and in two volumes on Information and Management Engineering (CCIS 235 and 236).
Genetic Programming
Author: Pierre ColletPublisher: Springer
ISBN: 3540331441
Category : Computers
Languages : en
Pages : 372
Book Description
This book constitutes the refereed proceedings of the 9th European Conference on Genetic Programming, EuroGP 2006, held in Budapest, Hungary, in April 2006, colocated with EvoCOP 2006. The 21 revised plenary papers and 11 revised poster papers were carefully reviewed and selected from 59 submissions. The papers address fundamental and theoretical issues, along with a wide variety of papers dealing with different application areas.
Author: Ilju Na
Author: Lizhong Wu