Now showing items 31-40 of 50
Detection of Target Speakers in Audio Databases
The problem of speaker detection in audio databases is addressed in this paper. Gaussian mixture modeling is used to build target speaker and background models. A detection algorithm based on a likelihood ratio calculation is applied to estimate target speaker segments. Evaluation procedures are defined in detail for this task. Results are given for ...
Noise Reduction Using an Undecimated Discrete Wavelet Transform
A new nonlinear noise reduction method is presented that uses the discrete wavelet transform. Similar to Donoho and Johnstone, we employ thresholding in the wavelet transform domain but, following a suggestion by Coifman, we use an undecimated, shift-invariant, nonorthogonal wavelet transform instead of the usual orthogonal one. This new approach can ...
Toward an Improved Understanding of Network Traffic Dynamics
Since the discovery of long range dependence in Ethernet LAN traces there has been significant progress in developing appropriate mathematical and statistical techniques that provide a physical-based, networking-related understanding of the observed fractal-like or self-similar scaling behavior of measured data traffic over time scales ranging from ...
Wavelet-Based Post-Processing of Low Bit Rate Transform Coded Images
In this paper we propose a novel method based on wavelet thresholding for enhancement of decompressed transform coded images. Transform coding at low bit rates typically introduces artifacts associated witht he basis functions of the transform. In particular, the method works remarkably well in "deblocking" of DCT compressed images. The method is ...
A Simple Scheme for Adapting Time-Frequency Representations
Signal-dependent time-frequency representations, by adapting their functional form to fit the signal being analyzed, offer many performance advantages over conventional representations. In this paper, we propose a simple, efficient technique for continuously adapting time-frequency representations over time. The procedure computes a short-time quality ...
SCAN - Speech Content Based Audio Navigator: A Systems Overview
SCAN (Speech Content based Audio Navigator) is a spoken document retrieval system integrating speaker-independent, large-vocabulary speech recognition with information-retrieval to support query-based retrieval of information from speech archives. Initial development focused on the application of SCAN to the broadcast news domain. This paper provides ...
Effect of Utterance Duration and Phonetic Content on Speaker Identification Usind Second Order Statistical Methods
Second-order statistical methods show very good results for automatic speaker identification in controlled recording conditions. These approaches are generally used on the entire speech material available. In this paper, we study the influence of the content of the test speech material on the performances of such methods, i.e. under a more analytical ...
An Overview of the AT&T Spoken Document Retrieval System
We present an overview of a spoken document retrieval system developed at AT&T Labs-Research for the HUB4 Broadcast News corpus. This overview includes a description of the intonational phrase boundary detection, classification, speech recognition, information retrieval and user interface components of the system, along with updated system assessments ...
An Improved Multifractal Formalism and Self Affine Measures
This document is a six page summary of my Ph.D. thesis in which multifractal formalism based on counting on coarse levels (as opposed to a dimensional approach) is developed. This formalism is then applied to self-affine measures discovering phase transitions which are not present with self-similar measures.
Opitmal Phase Kernels for Time-Frequency Analysis
We consider the design of kernels for time-frequency distributions through the phase, rather than amplitude, response. While phase kernels do not attenuate troublesome cross-components, they can translate them in the time-frequency plane. In contrast to previous work on phase kernels that concentrated on placing the cross- components on top of the ...