Articles

EM-Based Multiuser Detection in Fast Fading Multipath Environments

We address the problem of multiuser detection in fast fading multipath environments for DS-CDMA systems. In fast fading scenarios, temporal variations of the channel cause significant performance degradation e...

Authors: Mohammad Jaber Borran and Behnaam Aazhang

Joint Transmitter-Receiver Optimization in the Downlink CDMA Systems

To maximize the downlink code-division multiple access (CDMA) system capacity, we propose to minimize the total transmitted power of the system subject to users′ signal-to-interference ratio (SIR) requirements...

Authors: Mohammad Saquib and Habibul Islam

Dual Switched Predictive DIR MLSD Receiver for Dynamic Channels

A linear prefilter can be used to reduce the required complexity of a maximum likelihood sequence detector Viterbi algorithm (MLSD-VA) by shortening the overall channel and prefilter impulse response in dynami...

Authors: Michael Boyle and Anthony D. Fagan

Sequential Parameter Estimation of Time-Varying Non-Gaussian Autoregressive Processes

Parameter estimation of time-varying non-Gaussian autoregressive processes can be a highly nonlinear problem. The problem gets even more difficult if the functional form of the time variation of the process pa...

Authors: Petar M. Djurić, Jayesh H. Kotecha, Fabien Esteve and Etienne Perret

Spatial Block Codes Based on Unitary Transformations Derived from Orthonormal Polynomial Sets

Recent work in the development of diversity transformations for wireless systems has produced a theoretical framework for space-time block codes. Such codes are beneficial in that they may be easily concatenat...

Authors: Giridhar D. Mandyam

Chip-Level Channel Equalization in WCDMA Downlink

The most important third generation (3G) cellular communications standard is based on wideband CDMA (WCDMA). Receivers based on TDMA style channel equalization at the chip level have been proposed for a WCDMA ...

Authors: Kari Hooli, Markku Juntti, Markku J. Heikkilä, Petri Komulainen, Matti Latva-aho and Jorma Lilleberg

Simulation of Specular Surface Imaging Based on Computer Graphics: Application on a Vision Inspection System

This work aims at detecting surface defects on reflecting industrial parts. A machine vision system, performing the detection of geometric aspect surface defects, is completely described. The revealing of defe...

Authors: Ralph Seulin, Frederic Merienne and Patrick Gorria

Wafer Defect Detection Using Directional Morphological Gradient Techniques

Accurate detection and classification of wafer defects constitute an important component of the IC production process because together they can immediately improve the yield and also provide information needed...

Authors: Gongyuan Qu, Sally L. Wood and Cho Teh

Spatial and Spectral Methods for Weed Detection and Localization

This study concerns the detection and localization of weed patches in order to improve the knowledge on weed-crop competition. A remote control aircraft provided with a camera allowed to obtain low cost and re...

Authors: Jean-Baptiste Vioix, Jean-Paul Douzals, Frédéric Truchetet, Louis Assémat and Jean-Philippe Guillemin

A Multiagent System for Edge Detection and Continuity Perception on Fish Otolith Images

We present an algorithm for fish otolith growth ring detection using a multiagent system. Up to now, the identification of growth rings, for age estimation, is routinely achieved by human readers, but this tas...

Authors: Anne Guillaud, Herve Troadec, Abdesslam Benzinou, Jean Le Bihan and Vincent Rodin

Editorial

Authors: Luciano da F. Costa and Fabrice Meriaudeau

Defect Detection on Inclined Textured Planes Using the Shape from Texture Method and the Delaunay Triangulation

We present one method for detecting defects on an inclined textured plane. This method uses a combination of a shape from texture (SFT) method with the Delaunay triangulation technique. The SFT method provides...

Authors: Justin Plantier, Laurent Boutté and Sylvie Lelandais

Visual Inspection of Machined Metallic High-Precision Surfaces

This paper presents a surface inspection prototype of an automatic system for precision ground metallic surfaces, in this case bearing rolls. The surface reflectance properties are modeled and verified with op...

Authors: Franz Pernkopf and Paul O'Leary

Automated Quality Assurance Applied to Mammographic Imaging

Quality control in mammography is based upon subjective interpretation of the image quality of a test phantom. In order to suppress subjectivity due to the human observer, automated computer analysis of the Le...

Authors: Lilian Blot, Anne Davis, Mike Holubinka, Robert Martí and Reyer Zwiggelaar

Detection of Noncircularity and Eccentricity of a Rolling Winder by Artificial Vision

A common objective in the web transport industry is to increase the velocity as much as possible. Some disturbances drastically limit this velocity. Time-varying eccentricity of the rolling winder is one of th...

Authors: Christophe Doignon and Dominique Knittel

A Machine Vision Quality Control System for Industrial Acrylic Fibre Production

This paper describes the implementation of INFIBRA, a machine vision system used in the quality control of acrylic fibre production. The system was developed by INETI under a contract with a leading industrial...

Authors: Paulo Heleno, Roger Davies, Bento A. Brázio Correia and João Dinis

Content-Based Image Retrieval for Semiconductor Process Characterization

Image data management in the semiconductor manufacturing environment is becoming more problematic as the size of silicon wafers continues to increase, while the dimension of critical features continues to shri...

Authors: Kenneth W. Tobin, Thomas P. Karnowski, Lloyd F. Arrowood, Regina K. Ferrell, James S. Goddard and Fred Lakhani

Combined Frequency and Spatial Domain Algorithm for the Removal of Blocking Artifacts

A novel combined frequency and spatial domain method is presented in this paper for blockiness reduction for low bit rate compressed images. The method consists of two stages: in the first, better estimates of...

Authors: George A. Triantafyllidis, Dimitrios Tzovaras, Demetrios Sampson and Michael G. Strintzis

Temporal Segmentation of MPEG Video Streams

Many algorithms for temporal video partitioning rely on the analysis of uncompressed video features. Since the information relevant to the partitioning process can be extracted directly from the MPEG compresse...

Authors: Janko Calic and Ebroul Izquierdo

B-Spline Active Contour with Handling of Topology Changes for Fast Video Segmentation

This paper deals with video segmentation for MPEG-4 and MPEG-7 applications. Region-based active contour is a powerful technique for segmentation. However most of these methods are implemented using level sets...

Authors: Frederic Precioso and Michel Barlaud

A Standard-Compliant Virtual Meeting System with Active Video Object Tracking

This paper presents an H.323 standard compliant virtual video conferencing system. The proposed system not only serves as a multipoint control unit (MCU) for multipoint connection but also provides a gateway f...

Authors: Chia-Wen Lin, Yao-Jen Chang, Chih-Ming Wang, Yung-Chang Chen and Ming-Ting Sun

Tracking of Objects in Video Scenes with Time Varying Content

We propose a method for tracking of objects contained in video sequences. Each video object is represented by a set of polygonal regions. A bottom up approach (spatial segmentation/motion estimation) is applie...

Authors: Amal Mahboubi, Jenny Benois-Pineau and Dominique Barba

A 3-Step Algorithm Using Region-Based Active Contours for Video Objects Detection

We propose a 3-step algorithm for the automatic detection of moving objects in video sequences using region-based active contours. First, we introduce a very full general framework for region-based active cont...

Authors: Stéphanie Jehan-Besson, Michel Barlaud and Gilles Aubert

An Active Model for Facial Feature Tracking

We present a system for finding and tracking a face and extract global and local animation parameters from a video sequence. The system uses an initial colour processing step for finding a rough estimate of th...

Authors: Jörgen Ahlberg

A Novel Hexagonal Search Algorithm for Fast Block Matching Motion Estimation

Based on real-world image sequence characteristics of center-biased motion vector distribution, a Hexagonal (HS) algorithm with center-biased checking point pattern for fast block motion estimation is proposed...

Authors: Anastasios Hamosfakidis and Yakup Paker

Capacity Analysis Based on Using Adaptive Antenna Arrays Jointly Optimized for Trunking and Spatial Efficiency

Cellular systems using adaptive antennas for spatial processing have been shown to provide an increase in capacity. When employing adaptive antennas, the standard approach to achieve capacity gain has been to ...

Authors: Ivan Howitt and Fahed H. Awad

A Survey of Watermarking Algorithms for Image Authentication

Digital image manipulation software is now readily available on personal computers. It is therefore very simple to tamper with any image and make it available to others. Insuring digital image integrity has th...

Authors: Christian Rey and Jean-Luc Dugelay

Editorial

Authors: Moncef Gabbouj, Faouzi Alaya Cheikh, Bogdan Cramariuc and Geoff Morrison

Low-Complexity Iterative Receiver for Space-Time Coded Signals over Frequency Selective Channels

We propose a low-complexity turbo-detector scheme for frequency selective multiple-input multiple-output channels. The detection part of the receiver is based on a List-type MAP equalizer which is a state-redu...

Authors: Noura Sellami, Inbar Fijalkow and Mohamed Siala

Editorial

Authors: Dirk Slock, Vahid Tarokh and Xiang-Gen Xia

Maximum Likelihood Blind Channel Estimation for Space-Time Coding Systems

Sophisticated signal processing techniques have to be developed for capacity enhancement of future wireless communication systems. In recent years, space-time coding is proposed to provide significant capacity...

Authors: Hakan A. Çırpan, Erdal Panayırcı and Erdinc Çekli

Linear Equalization Combined with Multiple Symbol Decision Feedback Detection for Differential Space-Time Modulation

Differential space-time modulation (DSTM) for multiple antenna communication systems has been recently proposed for frequency-nonselective fading channels. In broadband multirate systems, frequency-selective f...

Authors: Genyuan Wang, Aijun Song and Xiang-Gen Xia

Space-Time Trellis Coded 8PSK Schemes for Rapid Rayleigh Fading Channels

This paper presents the design of 8PSK space-time (ST) trellis codes suitable for rapid fading channels. The proposed codes utilize the design criteria of ST codes over rapid fading channels. Two different app...

Authors: Salam A. Zummo and Saud A. Al-Semari

Blind Identification of Convolutive MIMO Systems with 3 Sources and 2 Sensors

We address the problem of blind identification of a convolutive Multiple-Input Multiple-Output (MIMO) system with more inputs than outputs, and in particular, the 3-input 2-output case. We assume that the inpu...

Authors: Binning Chen, Athina P. Petropulu and Lieven De Lathauwer

Pilot-Symbol-Assisted Channel Estimation for Space-Time Coded OFDM Systems

Space-time coded orthogonal frequency division multiplexing (OFDM) transmitter diversity techniques have been shown to provide an efficient means of achieving near optimal diversity gain in frequency-selective...

Authors: King F. Lee and Douglas B. Williams

Space-Time Turbo Trellis Coded Modulation for Wireless Data Communications

This paper presents the design of space-time turbo trellis coded modulation (ST turbo TCM) for improving the bandwidth efficiency and the reliability of future wireless data networks. We present new recursive ...

Authors: Welly Firmanto, Branka Vucetic, Jinhong Yuan and Zhuo Chen

On the Capacity of Certain Space-Time Coding Schemes

We take a capacity view of a number of different space-time coding (STC) schemes. While the Shannon capacity of multiple-input multiple-output (MIMO) channels has been known for a number of years now, the atta...

Authors: Constantinos B. Papadias and Gerard J. Foschini

Deterministic Blind Subspace MIMO Equalization

A subspace based approach for the blind multiple signal separation and recovery for MIMO systems is proposed in this paper. Instead of using the statistics of the received signal, the proposed algorithm exploi...

Authors: Balaji Sampath, K. J. Ray Liu and Ye (Geoffrey) Li

On Some Design Issues of Space-Time Coded Multi-Antenna Systems

This paper concerns some design issues and tradeoffs of communication systems equipped with multiple transmit and receive antennas. The general space-time coding/modulation structure by Tarokh et al. (1999) is...

Authors: Hsuan-Jung Su and Evaggelos Geraniotis

Maximum-Likelihood Sequence Detection of Multiple Antenna Systems over Dispersive Channels via Sphere Decoding

Multiple antenna systems are capable of providing high data rate transmissions over wireless channels. When the channels are dispersive, the signal at each receive antenna is a combination of both the current ...

Authors: Haris Vikalo and Babak Hassibi

Audio Classification in Speech and Music: A Comparison between a Statistical and a Neural Approach

We focus the attention on the problem of audio classification in speech and music for multimedia applications. In particular, we present a comparison between two different techniques for speech/music discrimin...

Authors: Alessandro Bugatti, Alessandra Flammini and Pierangelo Migliorati

SVD-Based Optimal Filtering Technique for Noise Reduction in Hearing Aids Using Two Microphones

We introduce a new SVD-based (Singular value decomposition) strategy for noise reduction in hearing aids. This technique is evaluated for noise reduction in a behind-the-ear (BTE) hearing aid where two omnidir...

Authors: Jean-Baptiste Maj, Marc Moonen and Jan Wouters

Video Segmentation Using Fast Marching and Region Growing Algorithms

The algorithm presented in this paper is comprised of three main stages: (1) classification of the image sequence and, in the case of a moving camera, parametric motion estimation, (2) change detection having ...

Authors: Eftychis Sifakis, Ilias Grinias and Georgios Tziritas

Editorial

Authors: Moncef Gabbouj, Faouzi Alaya Cheikh, Bogdan Cramariuc and Geoff Morrison

Stand-Alone Objective Segmentation Quality Evaluation

The identification of objects in video sequences, that is, video segmentation, plays a major role in emerging interactive multimedia services, such as those enabled by the ISO MPEG- ...

Authors: Paulo Lobato Correia and Fernando Pereira

Overview of the MPEG-7 Standard and of Future Challenges for Visual Information Analysis

This paper presents an overview of the MPEG- standard: the Multimedia Content Description Interface. It focuses on visual information d...

Authors: Philippe Salembier

Objective Evaluation Criteria for 2D-Shape Estimation Results of Moving Objects

The objective evaluation of 2D-shape estimation results for moving objects in a video sequence is still an open problem. First approaches in the literature evaluate the spatial accuracy and the temporal cohere...

Authors: Roland Mech and Ferran Marqués

Using Invariant Image Features for Synchronization in Spread Spectrum Image Watermarking

A watermarking scheme is presented in which the characteristics of both spatial and frequency techniques are combined to achieve robustness against image processing and geometric transformations. The proposed ...

Authors: Ebroul Izquierdo

Using MPEG- at the Consumer Terminal in Broadcasting

The European Union IST research programme SAMBITS (System for Advanced Multimedia Broadcast and IT Services) project is using Digital Video Broadcasting (DVB), the DVB Multimedia Home Platform (MHP) standard, ...

Authors: Alan Pearmain, Mounia Lalmas, Ekaterina Moutogianni, Damien Papworth, Pat Healey and Thomas Rölleke

Ordinal-Measure Based Shape Correspondence

We present a novel approach to shape similarity estimation based on distance transformation and ordinal correlation. The proposed method operates in three steps: object alignment, contour to multilevel image t...

Authors: Faouzi Alaya Cheikh, Bogdan Cramariuc, Mari Partio, Pasi Reijonen and Moncef Gabbouj