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Distributed Array Of Synchronized Sensors And Actuators

Rainer Lienhart, Igor Kozintsev, Igor Chikalov, Dmitry Budnikov
2004 Zenodo  
Publication in the conference proceedings of EUSIPCO, Viena, Austria, 2004
doi:10.5281/zenodo.38453 fatcat:f5mesrqz6zeo3o7a72nxpqd2ua

Probabilistic Semantic Video Indexing

Milind R. Naphade, Igor Kozintsev, Thomas S. Huang
2000 Neural Information Processing Systems  
We propose a novel probabilistic framework for semantic video indexing. We define probabilistic multimedia objects (multijects) to map low-level media features to high-level semantic labels. A graphical network of such multijects (multinet) captures scene context by discovering intra-frame as well as inter-frame dependency relations between the concepts. The main contribution is a novel application of a factor graph framework to model this network. We model relations between semantic concepts
more » ... terms of their co-occurrence as well as the temporal dependencies between these concepts within video shots. Using the sum-product algorithm [1] for approximate or exact inference in these factor graph multinets, we attempt to correct errors made during isolated concept detection by forcing high-level constraints. This results in a significant improvement in the overall detection performance.
dblp:conf/nips/NaphadeKH00 fatcat:pfmpwvjf3zdxtd5tdzlxzouqbm

Wikireality: Augmenting reality with community driven websites

Douglas Gray, Igor Kozintsev, Yi Wu, Horst Haussecker
2009 2009 IEEE International Conference on Multimedia and Expo  
We present a system for making community driven websites easily accessible from the latest mobile devices. Many of these new devices contain an ensemble of sensors such as cameras, GPS and inertial sensors. We demonstrate how these new sensors can be used to bring the information contained in sites like Wikipedia to users in a much more immersive manner than text or maps. We have collected a large database of images and articles from Wikipedia and show how a user can query this database by
more » ... y snapping a photo. Our system uses the location sensors to assist with image matching and the inertial sensors to provide a unique and intuitive user interface for browsing results.
doi:10.1109/icme.2009.5202738 dblp:conf/icmcs/GrayKWH09 fatcat:d6yawfjctfa5tc2k2232cgrr6i

To search or to label?

Lyndon S. Kennedy, Shih-Fu Chang, Igor V. Kozintsev
2006 Proceedings of the 8th ACM international workshop on Multimedia information retrieval - MIR '06  
In this work we explore the trade-offs in acquiring training data for image classification models through automated web search as opposed to human annotation. Automated web search comes at no cost in human labor, but sometimes leads to decreased classification performance, while human annotations come at great expense in human labor but result in better performance. The primary contribution of this work is a system for predicting which visual concepts will show the greatest increase in
more » ... ce from investing human effort in obtaining annotations. We propose to build this system as an estimation of the absolute gain in average precision (AP) experienced from using human annotations instead of web search. To estimate the AP gain, we rely on statistical classifiers built on top of a number of quality prediction features. We employ a feature selection algorithm to compare the quality of each of the predictors and find that cross-domain image similarity and cross-domain model generalization metrics are strong predictors, while concept frequency and within-domain model quality are weak predictors. In a test application, we find that the prediction scheme can result in a savings in annotation effort of up to 75%, while only incurring marginal damage (10% relative decrease in mean average precision) to the overall performance of the concept models.
doi:10.1145/1178677.1178712 dblp:conf/mir/KennedyCK06 fatcat:mhf2dlesgngw3jsqrinl374e2i

Accurate and fast system-level power modeling

Ankush Varma, Eric Debes, Igor Kozintsev, Paul Klein, Bruce Jacob
2008 ACM Transactions on Embedded Computing Systems  
Accurate and fast system modeling is central to the rapid design space exploration needed for embedded-system design. With fast, complex SoCs playing a central role in such systems, system designers have come to require MIPS-range simulation speeds and near-cycle accuracy. The sophisticated simulation frameworks that have been developed for high-speed system performance modeling do not address power consumption, although it is a key design constraint. In this paper, we define a simulation-based
more » ... methodology for extending system performance modeling frameworks to also include power modeling. We demonstrate the use of this methodology with a case study of a real, complex embedded system, comprising the Intel XScale embedded microprocessor, its WMMX SIMD co processor, L1 caches, SDRAM, and the on-board address and data buses. We describe detailed power models for each of these components and validate them against physical measurements from hardware, demonstrating that such frameworks enable designers to model both power and performance at high speeds without sacrificing accuracy. Our results indicate that the power estimates obtained are accurate within 5% of physical measurements from hardware, while simulation speeds consistently exceed a million instructions per second (MIPS).
doi:10.1145/1347375.1347378 fatcat:ej7iedr4cvfodgarpjczbbopsu

Accurate and fast system-level power modeling

Ankush Varma, Bruce Jacob, Eric Debes, Igor Kozintsev, Paul Klein
2007 ACM Transactions on Embedded Computing Systems  
Accurate and fast system modeling is central to the rapid design space exploration needed for embedded-system design. With fast, complex SoCs playing a central role in such systems, system designers have come to require MIPS-range simulation speeds and near-cycle accuracy. The sophisticated simulation frameworks that have been developed for high-speed system performance modeling do not address power consumption, although it is a key design constraint. In this paper, we define a simulation-based
more » ... methodology for extending system performance-modeling frameworks to also include power modeling. We demonstrate the use of this methodology with a case study of a real, complex embedded system, comprising the Intel XScale ® embedded microprocessor, its WMMX TM SIMD coprocessor, L1 caches, SDRAM and the on-board address and data buses. We describe detailed power models for each of these components and validate them against physical measurements from hardware, demonstrating that such frameworks enable designers to model both power and performance at high speeds without sacrificing accuracy. Our results indicate that the power estimates obtained are accurate within 5% of physical measurements from hardware, while simulation speeds consistently exceed a million instructions per second (MIPS).
doi:10.1145/1274858.1274864 fatcat:skgaygptnvfhnazcakn23ujxe4

Sampling Strategies for Active Learning in Personal Photo Retrieval

Yi Wu, Igor Kozintsev, Jean-yves Bouguet, Carole Dulong
2006 2006 IEEE International Conference on Multimedia and Expo  
With the advent and proliferation of digital cameras and computers, the number of digital photos created and stored by consumers has grown extremely large. This created increasing demand for image retrieval systems to ease interaction between consumers and personal media content. Active learning is a widely used user interaction model for retrieval systems, which learns the query concept by asking users to label a number of images at each iteration. In this paper, we study sampling strategies
more » ... r active learning in personal photo retrieval. In order to reduce human annotation efforts in a content-based image retrieval setting, we propose using multiple sampling criteria for active learning: informativeness, diversity and representativeness. Our experimental results show that by combining multiple sampling criteria in active learning, the performance of personal photo retrieval system can be significantly improved. MULTI-CRITERIA SAMPLING STRATEGIES FOR ACTIVE LEARNING Active learning processes training data incrementally, using the model learned "so far" to select particularly useful exam-
doi:10.1109/icme.2006.262442 dblp:conf/icmcs/WuKBD06 fatcat:g5xarifsrzajvckcxk7gj3zixm

Position calibration of audio sensors and actuators in a distributed computing platform

Vikas C. Raykar, Igor Kozintsev, Rainer Lienhart
2003 Proceedings of the eleventh ACM international conference on Multimedia - MULTIMEDIA '03  
In this paper, we present a novel approach to automatically determine the positions of sensors and actuators in an ad-hoc distributed network of heterogeneous general purpose computing platforms. The formulation and solution accounts for the limited precision in temporal synchronization. The theoretical performance limit for the sensor positions is derived via the Cramér-Rao bound. We analyze the sensitivity of localization accuracy with respect to the number of sensors and actuators as well as
more » ... their geometry. Extensive Monte Carlo simulation results are reported together with a discussion of the real-time system. In a distributed test platform consisting of 4 speakers and 4 microphones, the sensors' and actuators' three dimensional locations could be estimated with an average bias of 0.08 cm and average standard deviation of 3 cm. * This author can also be reached at vikas@umiacs.umd.edu.
doi:10.1145/957013.957133 dblp:conf/mm/RaykarKL03 fatcat:abxlpnnbnngcbbktss4nn6chf4

Universal synchronization scheme for distributed audio-video capture on heterogeneous computing platforms

Rainer Lienhart, Igor Kozintsev, Stefan Wehr
2003 Proceedings of the eleventh ACM international conference on Multimedia - MULTIMEDIA '03  
We propose a universal synchronization scheme for distributed audio-video capture on heterogeneous computing devices such as laptops, tablets, PDAs, cellular phones, audio recorders, and camcorders. These devices typically possess sensors such as microphones and possibly cameras. In order to combine them wirelessly into a distributed sensing and computing system, it is necessary to provide relative time synchronization among the distributed sensors. In this work we propose a setup and an
more » ... hm that provide synchronization between sampling times for a network of distributed multi-channel audio sensors connected to general purpose computing (GPC) platforms. Extensive experimental results on distributed acoustic Blind Source Separation (BSS) algorithms validate the performance of our synchronization scheme.
doi:10.1145/957013.957067 dblp:conf/mm/LienhartKW03 fatcat:ik4f434utzhndbs4lyt7qopcw4

Dual diffusion model of spreading activation for content-based image retrieval

Serhiy Kosinov, Stephane Marchand-Maillet, Igor Kozintsev, Carole Dulong, Thierry Pun
2006 Proceedings of the 8th ACM international workshop on Multimedia information retrieval - MIR '06  
This paper introduces a content-based information retrieval method inspired by the ideas of spreading activation models. In response to a given query, the proposed approach computes document ranks as their final activation values obtained upon completion of a diffusion process. This diffusion process, in turn, is dual in the sense that it models the spreading of the query's initial activation simultaneously in two similarity domains: low-level feature-based and highlevel semantic. The
more » ... n of the diffusion process relies on an approximation that makes it possible to compute the final activation as a solution to a linear system of differential equations via a matrix exponential without the need to resort to an iterative simulation. The latter calculation is performed efficiently by adapting a sparse routine based on Krylov subspace projection method. The empirical performance of the described dual diffusion model has been evaluated in terms of precision and recall on the task of content-based digital image retrieval in queryby-example scenario. The obtained experimental results demonstrate that the proposed method achieves better overall performance compared to traditional feature-based approaches. This performance improvement is attained not only when both similarity domains are used, but also when a diffusion model operates only on the feature-based similarities.
doi:10.1145/1178677.1178686 dblp:conf/mir/KosinovMKDP06 fatcat:b24yplat6zaalmr2ox5tgilcti

Position calibration of audio sensors and actuators in a distributed computing platform

Vikas C. Raykar, Igor Kozintsev, Rainer Lienhart
2003 Proceedings of the eleventh ACM international conference on Multimedia - MULTIMEDIA '03  
In this paper, we present a novel approach to automatically determine the positions of sensors and actuators in an ad-hoc distributed network of heterogeneous general purpose computing platforms. The formulation and solution accounts for the limited precision in temporal synchronization. The theoretical performance limit for the sensor positions is derived via the Cramér-Rao bound. We analyze the sensitivity of localization accuracy with respect to the number of sensors and actuators as well as
more » ... their geometry. Extensive Monte Carlo simulation results are reported together with a discussion of the real-time system. In a distributed test platform consisting of 4 speakers and 4 microphones, the sensors' and actuators' three dimensional locations could be estimated with an average bias of 0.08 cm and average standard deviation of 3 cm. * This author can also be reached at vikas@umiacs.umd.edu.
doi:10.1145/957131.957133 fatcat:7qvv7wvmvja6xmzitl6zyibvpq

Instruction-level power dissipation in the Intel XScale embedded microprocessor

Ankush Varma, Eric Debes, Igor Kozintsev, Bruce Jacob, Subramania Sudharsanan, V. Michael Bove, Jr., Sethuraman Panchanathan
2005 Embedded Processors for Multimedia and Communications II  
We present an instruction-level power dissipation model of the Intel XScale R microprocessor. The XScale implements the ARM TM ISA, but uses an aggressive microarchitecture and a SIMD Wireless MMX TM co-processor to speed up execution of multimedia workloads in the embedded domain. Instruction-Level power modelling was first proposed by Tiwari et. al. in 1994 . Adaptations of this model have been found to be applicable to simple ARM processors. Research also shows that instructions can be
more » ... red into groups with similar energy characteristics. We adapt these methodologies to the significantly more complex XScale processor. We characterize the processor in terms of the energy costs of opcode execution, operand values, pipeline stalls etc. through accurate measurements on hardware. This instruction-based (rather than microarchitectural) approach allows us to build a high-speed power-accurate simulator that runs at MIPS-range speeds, while achieving accuracy better than 5%. The processor core accounts only for a portion of overall power consumption, and we move beyond the core to explore the issues involved in building a SystemC simulation framework that models power dissipation of complete systems quickly, flexibly and accurately.
doi:10.1117/12.585564 fatcat:5sqdpl2qrbayxpdrglh3wlowze

A spatiotemporal decomposition strategy for personal home video management

Haoran Yi, Igor Kozintsev, Marzia Polito, Yi Wu, Jean-Yves Bouguet, Ara Nefian, Carole Dulong, Alan Hanjalic, Raimondo Schettini, Nicu Sebe
2007 Multimedia Content Access: Algorithms and Systems  
With the advent and proliferation of low cost and high performance digital video recorder devices, an increasing number of personal home video clips are recorded and stored by the consumers. Compared to image data, video data is lager in size and richer in multimedia content. Efficient access to video content is expected to be more challenging than image mining. Previously, we have developed a content-based image retrieval system and the benchmarking framework for personal images. In this
more » ... we extend our personal image retrieval system to include personal home video clips. A possible initial solution to video mining is to represent video clips by a set of key frames extracted from them thus converting the problem into an image search one. Here we report that a careful selection of key frames may improve the retrieval accuracy. However, because video also has temporal dimension, its key frame representation is inherently limited. The use of temporal information can give us better representation for video content at semantic object and concept levels than image-only based representation. In this paper we propose a bottom-up framework to combine interest point tracking, image segmentation and motion-shape factorization to decompose the video into spatiotemporal regions. We show an example application of activity concept detection using the trajectories extracted from the spatio-temporal regions. The proposed approach shows good potential for concise representation and indexing of objects and their motion in real-life consumer video.
doi:10.1117/12.704599 fatcat:jhybb72dwvhybcxq2uf3ypyzhu

Phase guided sampling for efficient parallel application simulation

Jeffrey Namkung, Dohyung Kim, Rajesh Gupta, Igor Kozintsev, Jean-Yves Bouget, Carole Dulong
2006 Proceedings of the 4th international conference on Hardware/software codesign and system synthesis - CODES+ISSS '06  
Simulating chip-multiprocessor systems (CMP) can take a long time. For single-threaded workloads, earlier work has shown the utility of phase analysis, that is identification of repetitive program behaviors, in reducing overall simulation time while maintaining an acceptable loss in accuracy. To cope with multithreaded workloads, a combination of phases from all executing threads must be taken into consideration since inter-thread interference may distort the homogeneity of each phases' true
more » ... formance. Unfortunately, phase analysis does not work for multithreaded (MT) workloads because the possible phase combinations in an inherently nondeterministic execution model grows exponentially with the number of threads. To this end, we propose a new technique to reduce the number of simulation samples by synthesizing samples from similar phase combinations. We present a simple cost function for measuring the similarity between phase combinations and by using the individual thread samples from the similar phase combinations, a new sample can be constructed. This cost function provides a convenient control knob for exploiting tradeoffs between simulation speed and accuracy. Our experimental results show that in most cases, properly setting the cost function's threshold can yield a reduction in sampling by 90%, while maintaining error to less than 5%.
doi:10.1145/1176254.1176301 dblp:conf/codes/NamkungKGKBD06 fatcat:ml2tbsj2rrh5thpnnhfchad5lm

Universal synchronization scheme for distributed audio-video capture on heterogeneous computing platforms

Rainer Lienhart, Igor Kozintsev, Stefan Wehr
2003 Proceedings of the eleventh ACM international conference on Multimedia - MULTIMEDIA '03  
We propose a universal synchronization scheme for distributed audio-video capture on heterogeneous computing devices such as laptops, tablets, PDAs, cellular phones, audio recorders, and camcorders. These devices typically possess sensors such as microphones and possibly cameras. In order to combine them wirelessly into a distributed sensing and computing system, it is necessary to provide relative time synchronization among the distributed sensors. In this work we propose a setup and an
more » ... hm that provide synchronization between sampling times for a network of distributed multi-channel audio sensors connected to general purpose computing (GPC) platforms. Extensive experimental results on distributed acoustic Blind Source Separation (BSS) algorithms validate the performance of our synchronization scheme.
doi:10.1145/957052.957067 fatcat:ecyo6ew2u5cenfcvx3dfimw7bi
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