An illusion of auditory space can be generated by the appropriate filtering of sounds presented over headphones: the so-called virtual auditory space (VAS). This book provides a bridge between many of the different disciplines that are involved in developing and exploiting this technology. The first part is fairly introductory in nature, while the second examines a number of issues relating to the generation of high fidelity virtual auditory space. The last two chapters review current research applications of VAS.

An illusion of auditory space can be generated by the appropriate filtering of sounds presented over headphones: the so-called virtual auditory space (VAS). This book provides a bridge between many of the different disciplines that are involved in developing and exploiting this technology. The first part is fairly introductory in nature, while the second examines a number of issues relating to the generation of high fidelity virtual auditory space. The last two chapters review current research applications of VAS.

Table of Contents --Auditory space -- The physcial and psychological basis of sound localization -- Digital signal processing for the auditory scientist: a tutorial introduction.

This three volume set provides the complete proceedings of the Ninth International Conference on Human-Computer Interaction held August, 2001 in New Orleans. A total of 2,738 individuals from industry, academia, research institutes, and governmental agencies from 37 countries submitted their work for presentation at the conference. The papers address the latest research and application in the human aspects of design and use of computing systems. Those accepted for presentation thoroughly cover the entire field of human-computer interaction, including the cognitive, social, ergonomic, and health aspects of work with computers. The papers also address major advances in knowledge and effective use of computers in a variety of diversified application areas, including offices, financial institutions, manufacturing, electronic publishing, construction, and health care.

158 2. Wiener Filtering 159 3. Speech Enhancement by Short-Time Spectral Modification 3. 1 Short-Time Fourier Analysis and Synthesis 159 160 3. 2 Short-Time Wiener Filter 161 3. 3 Power Subtraction 3. 4 Magnitude Subtraction 162 3. 5 Parametric Wiener Filtering 163 164 3. 6 Review and Discussion Averaging Techniques for Envelope Estimation 169 4. 169 4. 1 Moving Average 170 4. 2 Single-Pole Recursion 170 4. 3 Two-Sided Single-Pole Recursion 4. 4 Nonlinear Data Processing 171 5. Example Implementation 172 5. 1 Subband Filter Bank Architecture 172 173 5. 2 A-Posteriori-SNR Voice Activity Detector 5. 3 Example 175 6. Conclusion 175 Part IV Microphone Arrays 10 Superdirectional Microphone Arrays 181 Gary W. Elko 1. Introduction 181 2. Differential Microphone Arrays 182 3. Array Directional Gain 192 4. Optimal Arrays for Spherically Isotropic Fields 193 4. 1 Maximum Gain for Omnidirectional Microphones 193 4. 2 Maximum Directivity Index for Differential Microphones 195 4. 3 Maximimum Front-to-Back Ratio 197 4. 4 Minimum Peak Directional Response 200 4. 5 Beamwidth 201 5. Design Examples 201 5. 1 First-Order Designs 202 5. 2 Second-Order Designs 207 5. 3 Third-Order Designs 216 5. 4 Higher-Order designs 221 6. Optimal Arrays for Cylindrically Isotropic Fields 222 6. 1 Maximum Gain for Omnidirectional Microphones 222 6. 2 Optimal Weights for Maximum Directional Gain 224 6. 3 Solution for Optimal Weights for Maximum Front-to-Back Ratio for Cylindrical Noise 225 7. Sensitivity to Microphone Mismatch and Noise 230 8.

The two-volume set LNCS 8525-8526 constitutes the refereed proceedings of the 6th International Conference on Virtual, Augmented and Mixed Reality, VAMR 2014, held as part of the 16th International Conference on Human-Computer Interaction, HCI 2014, in Heraklion, Crete, Greece, in June 2014, jointly with 13 other thematically similar conferences. The total of 1476 papers and 220 posters presented at the HCII 2014 conferences were carefully reviewed and selected from 4766 submissions. These papers address the latest research and development efforts and highlight the human aspects of design and use of computing systems. The papers thoroughly cover the entire field of human-computer interaction, addressing major advances in knowledge and effective use of computers in a variety of application areas. The total of 82 contributions included in the VAMR proceedings were carefully reviewed and selected for inclusion in this two-volume set. The 43 papers included in this volume are organized in the following topical sections: VAMR in education and cultural heritage; games and entertainment; medical, health and rehabilitation applications; industrial, safety and military applications.

All natural auditory signals, including human speech and animal communication signals, are spectrally and temporally complex, that is, they contain multiple frequencies and their frequency composition, or spectrum, varies over time. The ability of hearers to identify and localize these signals depends on analysis of their spectral composition. For the overwhelming majority of human listeners spoken language is the major means of social communication, and this communication therefore depends on spectral analysis. Spectral analysis begins in the cochlea, but is then elaborated at various stages along the auditory pathways in the brain that lead from the cochlea to the cerebral cortex. The broad purpose of Auditory Spectral Processing is to provide a comprehensive account of the way in which spectral information is processed in the brain and the way in which this information is used by listeners to identify and localize sounds. Examines spectral processing mechanisms at different levels along the auditory neuraxis, from the cochlear nucleus to the cortex Reviews in detail psychophysical and neurophysiological evidence on the way in which spectral information is processed within and across frequency channels Presents information on the nature of the spectral information required for speech and music perception Examines a series of issues that relate to the role of spectral analysis in higher order/cognitive aspects of hearing and in clinical and applied contexts