Articles

Noncoherent Multiuser Communications: Multistage Detection and Selective Filtering

We consider noncoherent multiuser detection techniques for a system employing nonlinear modulation of nonorthogonal signals. Our aim is to investigate near-optimum noncoherent multiuser-detection techniques th...

Authors: Rajnish Sinha, Aylin Yener and Roy D. Yates

Blind Adaptive Decorrelating RAKE (DRAKE) Downlink Receiver for Space-Time Block Coded Multipath CDMA

A downlink receiver is proposed for space-time block coded CDMA systems operating in multipath channels. By combining the powerful RAKE receiver concept for a frequency selective channel with space-time decodi...

Authors: Sudharman K. Jayaweera and H. Vincent Poor

Simultaneous Principal-Component Extraction with Application to Adaptive Blind Multiuser Detection

SIPEX-G is a fast-converging, robust, gradient-based PCA algorithm that has been recently proposed by the authors. Its superior performance in synthetic and real data compared with its benchmark counterparts m...

Authors: Deniz Erdogmus, Yadunandana N. Rao, Kenneth E. Hild II and Jose C. Principe

Reduced-Rank Adaptive Filtering Using Krylov Subspace

A unified view of several recently introduced reduced-rank adaptive filters is presented. As all considered methods use Krylov subspace for rank reduction, the approach taken in this work is inspired from Kryl...

Authors: Sergueï Burykh and Karim Abed-Meraim

Space-Time Coded MC-CDMA: Blind Channel Estimation, Identifiability, and Receiver Design

Integrating the strengths of multicarrier (MC) modulation and code division multiple access (CDMA), MC-CDMA systems are of great interest for future broadband transmissions. This paper considers the problem of...

Authors: Wei Sun and Hongbin Li

Multiuser Delay-Tracking CDMA Receiver

We propose to integrate delay tracking into a successive interference cancellation (SIC) code division multiple access (CDMA) multiuser detector. Delay-robust SIC was initially proposed for CDMA multiuser dete...

Authors: Wei Zha and Steven D. Blostein

Blind Reduced-Rank MMSE Detector for DS-CDMA Systems

We first develop a reduced-rank minimum mean squared error (MMSE) detector for direct-sequence (DS) code division multiple access (CDMA) by forcing the linear MMSE detector to lie in a signal subspace of a red...

Authors: Xiaodong Cai, Hongya Ge and Ali N. Akansu

Multiuser Channel Estimation from Higher-Order Statistical Matrix Pencil

This paper presents a new statistical approach to the blind estimation of linear multiple-input multiple-output (MIMO) channels with finite impulse response. A matrix pencil is constructed from a set of fourth...

Authors: Jing Liang and Zhi Ding

Loudspeaker Equalization with Post-Processing

Loudspeaker equalization is an essential technique in audio system design. A well-known equalization scheme is based on the deconvolution of the desired equalized response with the measured impulse response of...

Authors: Wee Ser, Peng Wang and Ming Zhang

Dynamic Bayesian Networks for Audio-Visual Speech Recognition

The use of visual features in audio-visual speech recognition (AVSR) is justified by both the speech generation mechanism, which is essentially bimodal in audio and visual representation, and by the need for f...

Authors: Ara V. Nefian, Luhong Liang, Xiaobo Pi, Xiaoxing Liu and Kevin Murphy

Noise Adaptive Stream Weighting in Audio-Visual Speech Recognition

It has been shown that integration of acoustic and visual information especially in noisy conditions yields improved speech recognition results. This raises the question of how to weight the two modalities in ...

Authors: Martin Heckmann, Frédéric Berthommier and Kristian Kroschel

Statistical Lip-Appearance Models Trained Automatically Using Audio Information

We aim at modeling the appearance of the lower face region to assist visual feature extraction for audio-visual speech processing applications. In this paper, we present a neural network based statistical appe...

Authors: Philippe Daubias and Paul Deléglise

On the Relationship between Face Movements, Tongue Movements, and Speech Acoustics

This study examines relationships between external face movements, tongue movements, and speech acoustics for consonant-vowel (CV) syllables and sentences spoken by two male and two female talkers with differe...

Authors: Jintao Jiang, Abeer Alwan, Patricia A. Keating, Edward T. Auer Jr. and Lynne E. Bernstein

Editorial

Authors: Chalapathy Neti, Gerasimos Potamianos, Juergen Luettin and Eric Vatikiotis-Bateson

A Support Vector Machine-Based Dynamic Network for Visual Speech Recognition Applications

Visual speech recognition is an emerging research field. In this paper, we examine the suitability of support vector machines for visual speech recognition. Each word is modeled as a temporal sequence of visem...

Authors: Mihaela Gordan, Constantine Kotropoulos and Ioannis Pitas

Separation of Audio-Visual Speech Sources: A New Approach Exploiting the Audio-Visual Coherence of Speech Stimuli

We present a new approach to the source separation problem in the case of multiple speech signals. The method is based on the use of automatic lipreading, the objective is to extract an acoustic speech signal ...

Authors: David Sodoyer, Jean-Luc Schwartz, Laurent Girin, Jacob Klinkisch and Christian Jutten

Automatic Speechreading with Applications to Human-Computer Interfaces

There has been growing interest in introducing speech as a new modality into the human-computer interface (HCI). Motivated by the multimodal nature of speech, the visual component is considered to yield inform...

Authors: Xiaozheng Zhang, Charles C. Broun, Russell M. Mersereau and Mark A. Clements

Some Results on the Wavelet Packet Decomposition of Nonstationary Processes

Wavelet/wavelet packet decomposition has become a very useful tool in describing nonstationary processes. Important examples of nonstationary processes encountered in practice are cyclostationary processes or ...

Authors: Sami Touati and Jean-Christophe Pesquet

Moving-Talker, Speaker-Independent Feature Study, and Baseline Results Using the CUAVE Multimodal Speech Corpus

Strides in computer technology and the search for deeper, more powerful techniques in signal processing have brought multimodal research to the forefront in recent years. Audio-visual speech processing has bec...

Authors: Eric K. Patterson, Sabri Gurbuz, Zekeriya Tufekci and John N. Gowdy

Joint Audio-Visual Tracking Using Particle Filters

It is often advantageous to track objects in a scene using multimodal information when such information is available. We use audio as a complementary modality to video data, which, in comparison to vision, can...

Authors: Dmitry N. Zotkin, Ramani Duraiswami and Larry S. Davis

Audio-Visual Speech Recognition Using MPEG-4 Compliant Visual Features

We describe an audio-visual automatic continuous speech recognition system, which significantly improves speech recognition performance over a wide range of acoustic noise levels, as well as under clean audio ...

Authors: Petar S. Aleksic, Jay J. Williams, Zhilin Wu and Aggelos K. Katsaggelos

Real-Time Multi-Step View Reconstruction for a Virtual Teleconference System

We propose a real-time multi-step view reconstruction algorithm and we tune its implementation to a virtual teleconference application. Theoretical motivations and practical implementation issues of the algori...

Authors: B. J. Lei and E. A. Hendriks

A Bayesian Approach for Segmentation in Stereo Image Sequences

Stereoscopic image sequence processing has been the focus of considerable attention in recent literature for videoconference applications. A novel Bayesian scheme is proposed in this paper, for the segmentatio...

Authors: George A. Triantafylllidis, Dimitrios Tzovaras and Michael G. Strintzis

Model-Based Real-Time Head Tracking

This paper treats real-time tracking of a human head using an analysis by synthesis approach. The work is based on the Structure from Motion (SfM) algorithm from Azarbayejani and Pentland (1995). We will analy...

Authors: Jacob Ström

Three-Dimensional Facial Adaptation for MPEG-4 Talking Heads

This paper studies a new method for three-dimensional (3D) facial model adaptation and its integration into a text-to-speech (TTS) system. The 3D facial adaptation requires a set of two orthogonal views of the...

Authors: Nikos Grammalidis, Nikos Sarris, Fani Deligianni and Michael G. Strintzis

Image-Based Multiresolution Implicit Object Modeling

We discuss two image-based 3D modeling methods based on a multiresolution evolution of a volumetric function′s level set. In the former method, the role of the level set implosion is to fuse ("sew" and "stitch...

Authors: Augusto Sarti and Stefano Tubaro

Sliding Adjustment for 3D Video Representation

This paper deals with video coding of static scenes viewed by a moving camera. We propose an automatic way to encode such video sequences using several 3D models. Contrary to prior art in model-based coding wh...

Authors: Franck Galpin and Luce Morin

Mesh Simplification Using the Edge Attributes

This paper presents a novel technique for simplifying a triangulated surface at different levels of resolution. While most existing algorithms, based on iterative vertex decimation, employ the distance for err...

Authors: Il Dong Yun, Kyowoong Choo and Sang Uk Lee

Parameterized Facial Expression Synthesis Based on MPEG-4

In the framework of MPEG-4, one can include applications where virtual agents, utilizing both textual and multisensory data, including facial expressions and nonverbal speech help systems become accustomed to ...

Authors: Amaryllis Raouzaiou, Nicolas Tsapatsoulis, Kostas Karpouzis and Stefanos Kollias

Fingerprint Image Enhancement Based on Second Directional Derivative of the Digital Image

This paper presents a novel approach of fingerprint image enhancement that relies on detecting the fingerprint ridges as image regions where the second directional derivative of the digital image is positive. ...

Authors: Marius Tico, Vesa Onnia and Pauli Kuosmanen

Efficient Measurement of Shape Dissimilarity between 3D Models Using Z-Buffer and Surface Roving Method

Estimation of the shape dissimilarity between 3D models is a very important problem in both computer vision and graphics for 3D surface reconstruction, modeling, matching, and compression. In this paper, we pr...

Authors: In Kyu Park, Kyoung Mu Lee and Sang Uk Lee

Editorial

Authors: Michael G. Strintzis, Ferran Marques and Fabio Lavagetto

A Concept of Approximated Densities for Efficient Nonlinear Estimation

This paper presents the theoretical development of a nonlinear adaptive filter based on a concept of filtering by approximated densities (FAD). The most common procedures for nonlinear estimation apply the ext...

Authors: Virginie F. Ruiz

A Reduced-Complexity Fast Algorithm for Software Implementation of the IFFT/FFT in DMT Systems

The discrete multitone (DMT) modulation/demodulation scheme is the standard transmission technique in the application of asymmetric digital subscriber lines (ADSL) and very-high-speed digital subscriber lines (VD...

Authors: Tsun-Shan Chan, Jen-Chih Kuo and An-Yeu (Andy) Wu

High-Level Synthesis of DSP Applications Using Adaptive Negative Cycle Detection

The problem of detecting negative weight cycles in a graph is examined in the context of the dynamic graph structures that arise in the process of high level synthesis (HLS). The concept of adaptive negative cycl...

Authors: Nitin Chandrachoodan, Shuvra S. Bhattacharyya and K. J. Ray Liu

Lightweight Floating-Point Arithmetic: Case Study of Inverse Discrete Cosine Transform

To enable floating-point (FP) signal processing applications in low-power mobile devices, we propose lightweight floating-point arithmetic. It offers a wider range of precision/power/speed/area trade-offs, but...

Authors: Fang Fang, Tsuhan Chen and Rob A. Rutenbar

AVSynDEx: A Rapid Prototyping Process Dedicated to the Implementation of Digital Image Processing Applications on Multi-DSP and FPGA Architectures

We present AVSynDEx (concatenation of AVS SynDEx), a rapid prototyping process aiming to the implementation of digital signal processing...

Authors: Virginie Fresse, Olivier Déforges and Jean-François Nezan

Low-Complexity Versatile Finite Field Multiplier in Normal Basis

A low-complexity VLSI array of versatile multiplier in normal basis over is presented. The finite field parameters can be changed accord...

Authors: Hua Li and Chang Nian Zhang

Editorial

Authors: Yuke Wang and Yu Hen Hu

Design and DSP Implementation of Fixed-Point Systems

This article is an introduction to the FRIDGE design environment which supports the design and DSP implementation of fixed-point digital signal processing systems. We present the tool-supported transformation ...

Authors: Martin Coors, Holger Keding, Olaf Lüthje and Heinrich Meyr

Wavelet Kernels on a DSP: A Comparison between Lifting and Filter Banks for Image Coding

We develop wavelet engines on a digital signal processors (DSP) platform, the target application being image and intraframe video compression by means of the forthcoming JPEG2000 and Motion-JPEG2000 standards....

Authors: Stefano Gnavi, Barbara Penna, Marco Grangetto, Enrico Magli and Gabriella Olmo

A DSP Based POD Implementation for High Speed Multimedia Communications

In the cable network services, the audio/video entertainment contents should be protected from unauthorized copying, intercepting, and tampering. Point-of-deployment (POD) security module, proposed by

Authors: Chang Nian Zhang, Hua Li, Nuannuan Zhang and Jiesheng Xie

Partitioning and Scheduling DSP Applications with Maximal Memory Access Hiding

This paper presents an iteration space partitioning scheme to reduce the CPU idle time due to the long memory access latency. We take into consideration both the data accesses of intermediate and initial data....

Authors: Zhong Wang, Edwin Hsing-Mean Sha and Yuke Wang

Frequency Spectrum Based Low-Area Low-Power Parallel FIR Filter Design

Parallel (or block) FIR digital filters can be used either for high-speed or low-power (with reduced supply voltage) applications. Traditional parallel filter implementations cause linear increase in the hardw...

Authors: Jin-Gyun Chung and Keshab K. Parhi

P-CORDIC: A Precomputation Based Rotation CORDIC Algorithm

This paper presents a CORDIC (coordinate rotation digital computer) algorithm and architecture for the rotation mode in which the directions of all micro-rotations are precomputed while maintaining a constant ...

Authors: Martin Kuhlmann and Keshab K. Parhi

Editorial

Authors: Anand G. Dabak, Erik Dahlman and Giridhar D. Mandyam

On Bandwidth Efficient Modulation for High-Data-Rate Wireless LAN Systems

We address the problem of high-data-rate orthogonal frequency division multiplexed (OFDM) systems under restrictive bandwidth constraints. Based on recent theoretic results, multiple-input multiple-output (MIM...

Authors: John D. Terry, Juha Heiskala, Victor Stolpman and Majid Fozunbal

An Adaptive Channel Estimation Algorithm Using Time-Frequency Polynomial Model for OFDM with Fading Multipath Channels

Orthogonal frequency division multiplexing (OFDM) is an effective technique for the future 3G communications because of its great immunity to impulse noise and intersymbol interference. The channel estimation ...

Authors: Xiaowen Wang and K. J. Ray Liu

Reduced-Rank Chip-Level MMSE Equalization for the 3G CDMA Forward Link with Code-Multiplexed Pilot

This paper deals with synchronous direct-sequence code-division multiple access (CDMA) transmission using orthogonal channel codes in frequency selective multipath, motivated by the forward link in 3G CDMA sys...

Authors: Samina Chowdhury, Michael D. Zoltowski and J. Scott Goldstein

Performance of Reverse-Link Synchronous DS-CDMA System on a Frequency-Selective Multipath Fading Channel with Imperfect Power Control

We analyze the performance for reverse-link synchronous DS-CDMA system in a frequency-selective Rayleigh fading channel with an imperfect power control scheme. The performance degradation due to power control ...

Authors: Seung-Hoon Hwang and Duk Kyung Kim