检索结果-内蒙古大学图书馆

IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Kumar Viswanatha Sharadh Ramaswamy Ankur Saxena Kenneth Rose Department of Electrical and Computer Engineering University of California Santa Barbara CA 93106-9560 USA Mayachitra Inc. Santa Barbara USA Samsung Telecom Dallas USA

ISBN: (纸本)9781457705380

Canonical distributed quantization schemes do not scale to large sensor networks due to the exponential decoder storage complexity that they entail. Prior efforts to tackle this issue have largely been limited to the suboptimal schemes of source grouping and decoding, thus failing to use all available information at the decoder. We propose a new decoding paradigm where all received bits are used in decoding. Essentially, to decode each source, we partition the space of received bit-tuples using a nearest neighbor quantizer at a decoding rate consistent with the allowed complexity and each partition is then mapped to a reconstruction value for that source. To avoid local minima in design, we resort to deterministic annealing to determine the nearest neighbor partition function (the partitioning prototypes) from the training set. Results on several data-sets show substantial gains over naive and other competing approaches.

关键词： distributed coding large scale sensor networks data compression quantization codebook complexity

来源：评论

学校读者我要写书评

暂无评论

TOWARDS LARGE SCALE distributed coding

TOWARDS LARGE SCALE DISTRIBUTED CODING

引用

IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Sharadh Ramaswamy Kumar Viswanatha Ankur Saxena Kenneth Rose Department of Electrical and Computer Engineering University of California at Santa Barbara CA-93106

ISBN: (纸本)9781424442959

This paper considers the problem of distributed source coding for a large sensor network. A typical shortcoming of current approaches to true distributed coding is the exponential growth of the decoder codebook size with the number of sources in the network. This growth in complexity renders many traditional approaches impractical for even moderately sized sensor networks. Inspired by our recent results on fusion coding for selective retrieval, we propose a new distributed coding approach that scales to a large number of sources. Central to our approach is a "bit-subset selector" module whose role is to judiciously extract an appropriate subset of the received bits for decoding per individual source. This, together with joint design of all system components, enables direct optimization of the decoder complexity-distortion tradeoff, and thereby the desired scalability. Experiments on both real and synthetic data-sets show considerable gains over heuristic schemes.

关键词： distributed coding Sensor Network Compression Quantization Codebook Complexity

来源：评论

学校读者我要写书评

暂无评论

distributed SPATIAL coding IN THE SUPERIOR COLLICULUS - A REVIEW

引用

VISUAL NEUROSCIENCE 1991年第1期6卷 3-13页

作者： MCILWAIN, JT [a1 ]Division of Biology and Medicine Brown University Providence

This paper reviews evidence that the superior colliculus (SC) of the midbrain represents visual direction and certain aspects of saccadic eye movements in the distribution of activity across a population of cells. Accurate and precise eye movements appear to be mediated, in part at least, by cells of the SC that have large sensory receptive fields and/or discharge in association with a range of saccades. This implies that visual points or saccade targets are represented by patches rather than points of activity in the SC. Perturbation of the pattern of collicular discharge by focal inactivation modifies saccade amplitude and direction in a way consistent with distributed coding. Several models have been advanced to explain how such a code might be implemented in the colliculus. Evidence related to these hypotheses is examined and continuing uncertainties are identified.

关键词： SUPERIOR COLLICULUS SACCADE distributed coding ENSEMBLE coding POPULATION coding

来源：评论

学校读者我要写书评

暂无评论

distributed turbo coding with soft information relaying in wireless sensor networks

Distributed turbo coding with soft information relaying in w...

引用

International Conference on Computer as a Tool (EUROCON 2005)

作者： Li, YH Vucetic, B Univ Sydney Sch Elect & Informat Engn Sydney NSW 2006 Australia

ISBN: (纸本)142440049X

In this paper, we propose a novel distributed turbo coding (DTC) scheme for wireless sensor networks. In the proposed scheme, rather than making a decision on the transmitted information symbols at the relay as in the conventional DTC, the relay calculates and forwards the corresponding soft information. The proposed scheme can effectively overcome error propagation due to erroneous decoding at the relay, thus significantly outperforming the conventional DTC with imperfect decoding. At high signal to noise ratios (SNR), the proposed scheme can also approach the performance of the DTC with automatic repeat request (ARQ) and achieve much higher throughput than the latter.

关键词： distributed coding multi-hop wireless sensor network

来源：评论

学校读者我要写书评

暂无评论

distributed video coding of wyner-ziv frames using turbo trellis coded modulation

Distributed video coding of wyner-ziv frames using turbo tre...

引用

IEEE International Conference on Image Processing (ICIP 2006)

作者： Weerakkody, W. A. R. J. Fernando, W. A. C. Adikari, A. B. B. Rajatheva, R. M. A. P. Brunel Univ Sch Engn & Design Uxbridge UB8 3PH Middx England Asian Inst Technol Sch Engn TeleCommun Programme Pathum Thani Thailand

ISBN: (纸本)9781424404810

In this paper, we present a novel distributed video coding algorithm based on turbo trellis coded modulation (TTCM). As in the conventional turbo based Slepian-Wolf encoder, quantised information is applied to the TTCM encoder and parity bits are generated from both constituent encoders. However, TTCM symbols are not generated at the encoder since they are not sent to the decoder. Parity bits produced by the TTCM encoder are stored in a buffer and transmitted to the decoder upon request. TTCM symbols are generated at the decoder and these symbols are passed to the TTCM decoder for demodulation. Experimental results show that the proposed TTCM based codec can improve the PSNR by up to 6dB at the same bit rate with less memory compared to the turbo coded distributed video codecs.

关键词： video coding distributed coding Turbo trellis coded modulation

来源：评论

学校读者我要写书评

暂无评论

SCALABLE distributed SOURCE coding

SCALABLE DISTRIBUTED SOURCE CODING

引用

IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Saxena, Ankur Rose, Kenneth Univ Calif Santa Barbara Dept Elect & Comp Engn Santa Barbara CA 93106 USA

ISBN: (纸本)9781424423538

This paper considers the problem of scalable distributed coding of correlated sources that are communicated to a central unit. The general setting is typically encountered in sensor networks. The conditions of communication channels between the source encoders and fusion center may be time-varying and it is often desirable to guarantee a base layer of coarse information during channel fades. In addition the desired system should be robust to various scenarios of channel failure and should utilize all the available information to attain the best possible compression efficiency. Although a standard 'Lloyd-style' distributed coder design algorithm can be generalized to scalable distributed source coding, the resulting algorithm depends heavily on initialization and will virtually always converge to a poor local minimum on the distortion-cost surface. We propose an efficient initialization scheme for such a system, which employs a properly designed multi-stage distributed coder. In our prior work, we highlighted the fundamental conflict that arises when multi-stage coding is directly combined with distributed quantization. Here we use the multi-stage distributed coding system to initialize a scalable distributed coder and propose an iterative algorithm for joint design of all system components once the structural constraint is removed. Simulation results show considerable gains over randomly initialized scalable distributed coder design.

关键词： distributed coding scalable coding sensor networks

来源：评论

学校读者我要写书评

暂无评论

distributed IMAGE coding BASED ON INTEGRATED MARKOV MODELING AND LDPC DEcoding

DISTRIBUTED IMAGE CODING BASED ON INTEGRATED MARKOV MODELING...

引用

IEEE International Conference on Multimedia and Expo (ICME 2008)

作者： Zhang, Jinrong Li, Houqiang Chen, Chang Wen Univ Sci & Technol China Hefei 230026 Peoples R China

ISBN: (纸本)9781424425709

We present in this paper a novel distributed image coding scheme by exploiting image spatial correlation via Markov modeling at the decoding end. The exploitation of image statistics at the decoding end allows us to design a simple yet efficient encoder suitable for various energy efficient imaging sensor network applications. Existing distributed coding schemes developed for imaging sensor networks mostly attempt to exploit inter-image correlation. We develop in this research an integration of LDPC decoding and Markov model estimation in order to jointly exploit both inter-image and intra-image correlation. Simulations have been carried out to demonstrate that this Markov model-based approach is able to achieve significant gains over the schemes without Markov model. The simulation results also show that the 2D Markov model is able to achieve additional gains over the 1D Markov model.

关键词： distributed coding Markov model image statistics

来源：评论

学校读者我要写书评

暂无评论

Challenges and recent advances in distributed predictive coding

Challenges and recent advances in distributed predictive cod...

引用

IEEE Information Theory Workshop

作者： Saxena, Ankur Rose, Kenneth Univ Calif Santa Barbara Dept Elect & Comp Engn Santa Barbara CA 93106 USA

ISBN: (纸本)9781424415632

distributed coding of correlated sources with memory poses a number of considerable challenges that threaten practical applications, particularly (but not only) in the context of sensor networks. This problem is strongly motivated by the obvious observation that most common sources exhibit temporal correlations that may be at least as important as spatial or inter-source correlations. This paper presents an analysis of the underlying tradeoffs, paradigms for coding systems, and approaches for distributed predictive coder design optimization. Motivated by practical limitations on both complexity and delay (especially for dense sensor networks) the focus here is on predictive coding. From the source coding perspective, the most basic tradeoff (and difficulty) is due to conflicts that arise between distributed coding and prediction, wherein 'standard' distributed quantization of the prediction errors, if coupled with imposition of zero decoder drift, would drastically compromise the predictor performance and hence the ability to exploit temporal correlations. Another challenge arises from instabilities in the design of closed loop predictors, whose impact has been observed in the past, but is greatly exacerbated in the case of distributed coding. The main contribution focuses on the tradeoffs encountered within a more general paradigm where decoder drift is allowable or unavoidable, and must be effectively accounted for and controlled. We briefly review our earlier results on which we build to derive an overall design optimization method that avoids the pitfalls of naive distributed predictive quantization and produces an optimized low complexity and low delay coding system.

关键词： distributed coding prediction coding Sensor networks tradeoffs optimization method Error of prediction coding systems Distribute keylines

来源：评论

学校读者我要写书评

暂无评论

Using distributed source coding to secure fingerprint biometrics

Using distributed source coding to secure fingerprint biomet...

引用

32nd IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Draper, Stark C. Khisti, Ashish Martinian, Emin Vetro, Anthony Yedidia, Jonathan S. MERL 201 Broadway Ave Cambridge MA 02139 USA

ISBN: (纸本)1424407281

We describe a method to encode fingerprint biometrics securely for use, e.g., in encryption or access control. The system is secure because the stored data does not suffice to recreate the original fingerprint biometric. Therefore, a breach in database security does not lead to the loss of biometric data. At the same time the stored data suffices to validate a probe fingerprint. Our approach is based on the use of distributed source coding techniques implemented with graph-based codes. We present a statistical model of the relationship between the enrollment biometric and the (noisy) biometric measurement taking during authentication. We describe how to validate or reject a candidate biometric probe given the probe and the stored encoded data. We report the effectiveness of our method as tested on a database consisting of 579 data sets, each containing roughly 15 measurements of a single finger. We thereby demonstrate a working secure biometric system for fingerprints.

关键词： biometric fingerprint distributed coding Slepian-Wolf coding belief propagation decoding

来源：评论

学校读者我要写书评

暂无评论

distributed AUDIO coding WITH EFFICIENT SOURCE CORRELATION EXTRACTION

DISTRIBUTED AUDIO CODING WITH EFFICIENT SOURCE CORRELATION E...

引用

13th IEEE Digital Signal Processing Workshop/5th IEEE Signal Processing Education Workshop

作者： Matta, Sandeep Creusere, Charles D. New Mexico State Univ Klipsch Sch Elect & Comp Engn Las Cruces NM 88003 USA

ISBN: (纸本)9781424436767

distributed source coding is one of the enabling technologies for efficient bandwidth utilization in wireless sensor networks and is consequently of great current interest. This paper studies its application to audio signals, using a transform weighted interleaved vector quantization (TWIN-VQ) framework and allowing a sensor node to passively receive and use information from neighboring sensors that is being transmitted to the common joint decoder. Specifically, it uses the linear predictor coefficients generated as side information by TWIN-VQ for one source to determine its frame-by-frame correlations with another source and then conditionally encode MDCT coefficients of the second source. Based on conditional entropy calculations, exploitation of this correlation results in potential improvements of 54-58% in coding efficiency. Using a multi-context adaptive arithmetic coder, an actual bitrate reduction of 38% is achieved.

关键词： distributed coding audio processing bitstream processing audio compression TWIN-VQ

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：