检索结果-内蒙古大学图书馆

A distortion-minimizing rate controller for wireless multimedia sensor networks

COMPUTER COMMUNICATIONS 2010年第12期33卷 1380-1390页

作者： Pudlewski, Scott Melodia, Tommaso SUNY Buffalo Dept Elect Engn Wireless Networks & Embedded Syst Lab Buffalo NY 14260 USA

The availability of inexpensive CMOS cameras and microphones that can ubiquitously capture multimedia content from the environment is fostering the development of wireless multimedia sensor networks (WMSNs), i.e., distributed systems of wirelessly networked devices that can retrieve video and audio streams, still images, and scalar sensor data. A new cross-layer rate control scheme for WMSNs is introduced in this paper with a twofold objective: (i) maximize the video quality of each individual video stream;(ii) maintain fairness in the domain of video quality between different video streams. The rate control scheme is based on analytical and empirical models of video distortion and consists of a new cross-layer control algorithm that jointly regulates the end-to-end data rate, the video quality, and the strength of the channel coding at the physical layer. The end-to-end data rate is regulated to avoid congestion while maintaining fairness in the domain of video quality rather than data rate. Once the end-to-end data rate has been determined, the sender adjusts the video encoder rate and the channel encoder rate based on the overall rate and the current channel quality, with the objective of minimizing the distortion of the received video. Simulations show that the proposed algorithm considerably improves the received video quality with respect to state-of-the art rate control algorithms, without sacrificing on fairness. (C) 2010 Elsevier B.V. All rights reserved.

关键词： multimedia sensor networks Cross-layer design Rate control

来源：评论

学校读者我要写书评

暂无评论

A distortion-minimizing rate controller for wireless multimedia sensor networks

A distortion-minimizing rate controller for wireless multime...

引用

作者： Pudlewski, Scott Melodia, Tommaso at Buffalo Buffalo NY United States

关键词： Wireless sensor networks

来源：评论

学校读者我要写书评

暂无评论

Multi-method audio-based retrieval of multimedia information

引用

WSEAS Transactions on Information Science and Applications 2010年第2期7卷 310-319页

作者： Malcangi, Mario DICo - Dipartimento di Informatica e Comunicazione Università Degli Studi di Milano Via Comelico 39 20135 Milano Italy

multimedia information and embedded systems are two major technological advances that have significantly changed the way people interact with systems and information in recent years. In this context, audio proves to be the most advantageous media for interacting with embedded systems and their content. Advantages include: hands-free operation;unattended interaction;and simple, cheap devices for capture and playback. The use of embedded systems to seek information stored locally or on the web points up several difficulties inherent in the nature of multimedia-information signals. These difficulties are especially evident when palmtop or deeply embedded devices are used for such purposes. Developing a set of digital-signal-processing- based algorithms for extracting audio information is a primary step toward providing user-friendly access to multimedia information and developing powerful communication interfaces. The algorithms aim to extract semantic and syntactic information from audio signals, including voice. Extracted audio features are employed to access information in multimedia databases, as well as to index it. More extensive, higher-level information, such as audio-source identification (speaker identification) and genre (in the case of music), must be extracted from the audio signal. One basic task involves transforming audio into symbols (e.g. music transformed into a score, speech transformed into text) and transcribing symbols into audio (e.g. score transformed into musical audio, text transformed into speech). The purpose is to search for and access any kind of multimedia information by means of audio. To attain these results, digital audio-processing, digital speech-processing, and soft-computing methods need to be integrated. Neural networks are used as classifiers and fuzzy logic is used for making smart decisions.

关键词： Music

来源：评论

学校读者我要写书评

暂无评论

Proceedings of SPIE-IS and T Electronic Imaging - multimedia content access: algorithms and systems iiI

Proceedings of SPIE-IS and T Electronic Imaging - Multimedia...

引用

multimedia content access: algorithms and systems iiI

The proceedings contain 15 papers. The topics discussed include: discriminative genre-independent audio-visual scene change detection;a random walk through human behavior;flexible user interface for efficient content-based video surveillance retrieval: design and evaluation;an automated object-level video editing tool;ImageSeeker: a content-based image retrieval system;extraction of salient regions of interest using visual attention models;research on subjective stereoscopic image quality assessment;image quality assessment in multimedia applications;document description: what works for images should also work for text?;an annotation database for multimedia scientific data;a model of multimodal fusion for medical applications;and binary and nonbinary description of hypointensity for search and retrieval of brain MR images.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Image quality assessment in multimedia applications

Image quality assessment in multimedia applications

引用

multimedia content access: algorithms and systems iiI

作者： Ciocca, G. Marini, F. Schettini, R. DISCo Dipartimento di Informatica Sistemistica e Comunicazione Universita Degli Studi di Milano-Bicocca Viale Sarca 336 20126 Milano Italy

In the framework of multimedia applications image quality may have different meanings and interpretations. In this paper, considering the quality of an image as the degree of adequacy to its function/goal within a specific application field, we provide an organized overview of image quality assessment methods by putting in evidence their applicability and limitations in different application domains. Three scenarios have been chosen representing three typical applications with different degree of constraints in their image workflow chains and requiring different image quality assessment methodologies. ©2009 SPIE-IS&T.

关键词： Image quality

来源：评论

学校读者我要写书评

暂无评论

Semantic classification, low level features and relevance feedback for content-based image retrieval

Semantic classification, low level features and relevance fe...

引用

multimedia content access: algorithms and systems iiI

作者： Ciocca, G. Cusano, C. Schettini, R. DISCo Dipartimento di Informática Sistemistica e Comunicazione Universita degli Studi di Milano-Bicocca Viale Sarca 336 20126 Milano Italy

Although traditional content-based retrieval systems have been successfully employed in many multimedia applications, the need for explicit association of higher concepts to images has been a pressing demand from users. Many research works have been conducted focusing on the reduction of the semantic gap between visual features and the semantics of the image content. In this paper we present a mechanism that combines broad high level concepts and low level visual features within the framework of the QuickLook content-based image retrieval system. This system also implements a relevance feedback algorithm to learn users' intended query from positive and negative image examples. With the relevance feedback mechanism, the retrieval process can be efficiently guided toward the semantic or pictorial contents of the images by providing the system with the suitable examples. The qualitative experiments performed on a database of more than 46,000 photos downloaded from the Web show that the combination of semantic and low level features coupled with a relevance feedback algorithm, effectively improve the accuracy of the image retrieval sessions. © 2009 SPIE-IS&T.

关键词： Semantics

来源：评论

学校读者我要写书评

暂无评论

ImageSeeker: A content-based image retrieval system

ImageSeeker: A content-based image retrieval system

引用

multimedia content access: algorithms and systems iiI

作者： Tawfik, Alaa Fouad, HebatAllah Megahed, Reem Mohamed, Samar Hemayed, Elsayed Computer Engineering Dept. Faculty of Engineering Cairo University Giza Egypt

In many areas of commerce, government, academia, and medicine, large collections of digital images are being used. Usually, the only way of searching these collections is by their name, or by browsing which is unpractical for large number of images. ImageSeeker aims at providing an improved technique to enhance image searching. It focuses on extracting visual contents from images and annotating them;it is based on the concept of CBIR (content Based Image Retrieval) to retrieve the contents of the image based on what it has learnt during past trainings. When a user requests an image for a certain object, all images containing the same object will show up. ImageSeeker maintains high accuracy in finding matching results to the user's query. The system was tested on images containing natural scenes, specifically, see, sand, grass, clouds and sky. © 2009 SPIE-IS&T.

关键词： Search engines

来源：评论

学校读者我要写书评

暂无评论

Flexible user interface for efficient content-based video surveillance retrieval: Design and evaluation

Flexible user interface for efficient content-based video su...

引用

multimedia content access: algorithms and systems iiI

作者： Meessen, Jerome Coterot, Mathieu De Vleeschouwer, Christophe Desurmont, Xavier Macq, Benoit Multitel B-7000 Mons Belgium Université Catholique de Louvain Communication and Remote Sensing Lab. Louvain-la-Neuve Belgium

The major drawback of interactive retrieval systems is the potential frustration of the user that is caused by an excessive labelling work. Active learning has proven to help solving this issue, by carefully selecting the examples to present to the user. In this context, the design of the user interface plays a critical role since it should invite the user to label the examples elected by the active learning. This paper presents the design and evaluation of an innovative user interface for image retrieval. It has been validate using real-life IEEE PETS video surveillance data. In particular, we investigated the most appropriate repartition of the display area between the retrieved video frames and the active learning examples, taking both objective and subjective user satisfaction parameters into account. The flexibility of the interface relies on a scalable representation of the video content such as Motion JPEG 2000 in our implementation. © 2009 SPIE-IS&T.

关键词： User interfaces

来源：评论

学校读者我要写书评

暂无评论

QoS-Oriented content Delivery in E-Learning systems

QoS-Oriented Content Delivery in E-Learning Systems

引用

IEEE International Symposium on IT in Medicine and Education

作者： Xu, Shihong Shen, Hong Univ Adelaide Sch Comp Sci Adelaide SA 5005 Australia

ISBN: (纸本)9781424439294

QoS-oriented content delivery is an important component in en-learning systems. In this paper we study the object placement problem in the parallel-access context for QoS-oriented content delivery. The problem is formulated in terms of bandwidth maximization and further proved to be equivalent to the Fault Tolerant Facility Location Problem (FTFL). In this problem the bandwidth that violates the triangle inequality is measured by a cost function which forms a metric when the shortest-path routing is deployed. Though there have been efficient UFL algorithms with good performance guarantees, the challenge of the FTFL Problem arises due to the conflict of its connectivity requirement (multiple distinct connections) and cost minimization (which leads to identical connections with the minimum cost). We investigate possible solutions for addressing this conflict after giving an overview of the existing techniques. Extension of the problem to the context of QoE-aware multimedia delivery which has important applications in e-learning systems is also discussed.

关键词： Bandwidth

来源：评论

学校读者我要写书评

暂无评论

Learning approach for multi content analysis of compound images

Learning approach for multi content analysis of compound ima...

引用

multimedia content access: algorithms and systems iiI

作者： Besnehard, Quentin Marchessoux, Cédric Kimpe, Tom Spalla, Guillaume Joubel, Arnaud Boudet, François Barco n.v. President Kennedypark 35 8500 Kortrijk Belgium IUP Génie Physiologique et Informatique University of Poitiers 40 av du Recteur Pineau 86022 Poitiers France

In the context of the European Cantata project (ITEA project, 2006-2009), within Barco, a complete Multi-content Analysis framework was developed for detection and analysis of compound images. The framework consists of: a dataset, a Multi-content Analysis (MCA) algorithm based on learning approaches, a Ground Truth, an evaluation module based on metrics and a presentation module. The aim of the MCA methodology presented here is to classify image content of computer Screenshots into different categories such as: text;Graphical User Interface;Medical images and other complex images. The AdaBoost meta-algorithm was chosen, implemented and optimized for the classification method as it fitted the constraints (real-time and precision). A large dataset separated in training and testing subsets and their ground truth (with ViPER metadata format) was both collected and generated for the four different categories. The outcome of the MCA is a cascade of strong classifiers trained and tested on the different subsets. The obtained framework and its optimization (binary search, pre-computing of the features, pre-sorting) allow to re-train the classifiers as much as needed. The preliminary results are quite encouraging with a low false positive rate and close true positive rate in comparison with expectations. The re-injection of false negative examples from new testing subsets in the training phase resulted in better performances of the MCA. © 2009 SPIE-IS&T.

关键词： Adaptive boosting

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：