Brian Katz - Academia.edu (original) (raw)
Papers by Brian Katz
international conference on auditory display, Jul 1, 2015
In the absence of a well suited measure for quantifying binaural data variations, this study pres... more In the absence of a well suited measure for quantifying binaural data variations, this study presents the use of a global perceptual distance metric which can describe both HRTF as well as listener similarities. The metric is derived based on subjective evaluations of binaural renderings of a sound moving along predefined trajectories in the horizontal and median planes. Its characteristics and advantages in describing data distributions based on perceptually relevant attributes are discussed. In addition, the use of 24 HRTFs from two different databases of origin allows for an evaluation of the perceptual impact of some database-dependent characteristics on spatialization. The effectiveness of the experimental design as well as the correlation between the HRTF evaluations of the two plane trajectories are also discussed. This work was funded in part by the French FUI project BiLi ("Binaural Listening", www.bili-project.org, FUI-AAP14)
Proceedings of the 12th International Audio Mostly Conference on Augmented and Participatory Sound and Music Experiences, 2017
Our demonstration presents recent developments of the EVERTims project, an auralization framework... more Our demonstration presents recent developments of the EVERTims project, an auralization framework for virtual acoustics and real-time room acoustic simulation. The developments presented here concern the complete re-design of the scene graph editor unit, and the C++ implementation of a new spatial renderer based on the JUCE framework. EVERTims now functions as a Blender add-on to support real-time auralization of any 3D room model, both for its creation in Blender and its exploration in the Blender Game Engine. The EVERTims framework is published as open source software.
Virtual Reality (VR) reconstructions of architectural acoustics situations are used in the contex... more Virtual Reality (VR) reconstructions of architectural acoustics situations are used in the context of design and renovation projects for acoustically sensitive spaces and historical studies. In such studies, it is important to understand the impact of the visual rendering on auditory perceptions of the spaces concerned. For such a study, a virtual scenario was created, comprising the rendering of a theatrical performance, staged in a 3D visual model of an actual theater. The theater’s acoustics were numerically simulated using a geometrical acoustics model which was calibrated to in-situ measurements. The virtual scene was rendered on both a CAVE-light system and a Head Mounted Display (HMD) for various seating positions. Auralization, the audio rendering of the architectural acoustic simulation, was achieved using dynamic binaural processing of Ambisonic streams over headphones. Positionally matched and mismatched audio-visual configurations were presented in order to study the imp...
Proceedings of the …, Jun 24, 2008
This study presents an exploration task using interactive sonification to compare different son... more This study presents an exploration task using interactive sonification to compare different sonification mapping concepts. Based on the real application of protein-protein docking within the CoRSAIRe project («Combinaisons de Rendus Sensori-moteurs pour l'Analyse Immersive de Résultats», or Combination of sensori-motor rendering for the immersive analysis of results), an abstraction of the task was developed which simulates the basic concepts involved. Two conditions were evaluated, the inclusion or absence of spatialized ...
The Journal of the Acoustical Society of America, 2021
The Journal of the Acoustical Society of America, 2017
The Inter-aural Time Difference (ITD) is a fundamental cue for human sound localization. Over the... more The Inter-aural Time Difference (ITD) is a fundamental cue for human sound localization. Over the past decades, several methods have been proposed for its estimation from measured Head-Related Impulse Response (HRIR) data. Nevertheless, inter-method variations in ITD calculation have been found to exceed the known Just Noticeable Differences (JNDs), hence leading to possible perceptible artifacts in virtual binaural auditory scenes, even for cases when personalized HRIRs are being used. In the absence of an objective means for validating ITD estimations, this paper evaluates which methods lead to the most perceptually relevant results. A subjective lateralization study compared objective ITDs to perceptually driven inter-aural pure delay offsets. Results clearly indicate the first-onset Threshold detection method, using a low relative threshold of -30 dB, applied on 3 kHz low-pass filtered HRIRs as the most perceptually relevant procedure across various metrics. Alternative threshold values and methods ba...
The Journal of the Acoustical Society of America, 2017
As part of the 850-year anniversary of Notre-Dame cathedral, Paris, there was a special performan... more As part of the 850-year anniversary of Notre-Dame cathedral, Paris, there was a special performance of “La Vierge.” A close-mic recording of the concert was made by the Conservatoire de Paris. In an attempt to provide a new type of experience, a virtual recreation of the performance using these roughly 45 audio channels was made via auralization. A computational acoustic model was created and calibrated based on in-situ measurements for reverberation and clarity parameters. A perceptual study with omnidirectional source and binaural receiver validated the calibrated simulation for the tested subjective attributes of reverberation, clarity, source distance, tonal balance, coloration, plausibility, ASW, and LEV when compared to measured responses. Instrument directivity was included for each track's representative orchestral section based on published data. Higher-Order Ambisonic (3rd order) RIRs were generated for all source and receiver combinations using the CATT-Acoustic TUCT software. Virtual navigatio...
The Journal of the Acoustical Society of America, 2015
American Journal of Engineering and Applied Sciences, 2021
The main aim of the work is to assess physical parameters of forest woodchips and their impact on... more The main aim of the work is to assess physical parameters of forest woodchips and their impact on the prices achieved by the supplier in transactions with a power plant. During fragmentation of logging residue, high content of green matter and contaminants negatively impacts the quality parameters that serve as basis for settlements. The analysis concerns data on the main parameters-water content, fuel value, sulphur and ash content-from 252 days of deliveries of forest chips to a power plant. The deliveries were realised from forested areas on an average about 340 km from the plant. Average water content and the resultant fuel value of forest chips was within 27-47% and 8.7-12.9 GJ×Mg −1 (appropriately), respectively. They depend on the month in which they are delivered to the power plant. The threshold values for the above-mentioned parameters are set by the plant at a real level and the suppliers have no problems with meeting them. The parameter that is most frequently exceeded is ash content (11.5% of cases). The settlement system does not differentiate on the basis of the transport distance but gives possibility to lower the settlement price when the quality parameters are not met but provides no reward for deliveries with parameters better than the average ones. On the basis of results obtained, it was calculated that average annual settlement price is lower than the contract price by about 0.20 PLN×GJ −1 , which in case of the analysed company may translate into an average daily loss of about 700 PLN.
The Cathedrale Notre-Dame de Paris is amongst the most well-known worship spaces in the world. It... more The Cathedrale Notre-Dame de Paris is amongst the most well-known worship spaces in the world. Its large volume, in combination with a relatively bare stone construction and marble floor, leads to rather long reverberation times. The cathedral suffered from a significant fire in 2019, resulting in damage primarily to the roof and vaulted ceiling. Despite the notoriety of this space, there are few examples of published data on the acoustical parameters of this space, and these data do not agree. Archived measurement recordings from 1987 were recovered and found to include several balloon bursts. In 2015, a measurement session was carried out for a virtual reality project. Comparisons between results from these two sessions show a slight but significant decrease in reverberation time (8%) in the pre-fire state. Measurements were recently carried out on the construction site, 1 year since the fire. Compared to 2015 data, the reverberation time significantly decreased (20%). This paper ...
This article presents a case study of higher-order Ambisonics (HOA) for real-time sound field rep... more This article presents a case study of higher-order Ambisonics (HOA) for real-time sound field reproduction in a small room with a 157-loudspeaker array. It addresses a number of specific questions and practical issues on the system design and implementation, such as the reproduction room's acoustic, loudspeaker positioning and radiation patterns, distributed computing and audio channel synchronization, and in more general the achievable accuracy of sound field reproduction. In the current configuration of the system Ambisonics up to order n = 6 is applied and the decoders are rendered in parallel on a cluster of four computers. For this reason, synchronization and communication between the different computers becomes a challenging task for achieving a good system performance. The overall system latency and the inter-channel synchronicity have been measured using time-stretched pulse (TSP) signals. The measurement results have shown a maximum (unsigned) latency of 51 samples, which corresponds to t = 1.1 ms. It is obvious that the acoustic of the reproduction room has a strong effect on the accuracy of the Ambisonics sound field reproduction. To achieve semi-anechoic conditions sound absorption materials have been installed in the room. Finally, spatial filters have been applied to each individual loudspeaker to correct for different orientations with reference to the sweet spot. These filters have been derived from radiation pattern measurements in an anechoic chamber.
Considerations in characterising an almost anechoic room for interactive spatial audio reproducti... more Considerations in characterising an almost anechoic room for interactive spatial audio reproduction Densil Cabrera (1), Takuma Okamoto (2), Brian F.G. Katz (3), Markus Noisternig (4), Yukio Iwaya (2) and Yo-iti Suzuki (2)
The Journal of the Acoustical Society of America
This presentation will provide an overview of recent and ongoing studies regarding evaluations of... more This presentation will provide an overview of recent and ongoing studies regarding evaluations of sound fields using virtual loudspeaker binaural synthesis. Of specific interest is an identification of perceptual attributes affected by Head-Related Transfer Function (HRTF) choice beyond basic localization error and the sensitivity of listeners to head tracking with regards to latency and externalization judgments. A list of perceptual attributes, created using a Consensus Vocabulary Protocol elicitation method, and validated through listening tests, resulted in eight valid perceptual attributes for describing the perceptual dimensions affected by HRTF set variations. Employing prescribed head movements, sensitivity to head tracker latency showed small but significant differences between single and multichannel audio source scenes. A similar protocol was employed to comparing the sense of externalization as a function of head rotation with and without head tracking. In contrast to several previous studies,...
Notre-Dame de Paris is amongst the most well-known worship spaces in the world. Its large volume,... more Notre-Dame de Paris is amongst the most well-known worship spaces in the world. Its large volume, in combination with a relatively bare stone construction and marble floor, leads to rather long reverberation times. Despite the notoriety of this space, there are few examples of published data on the acoustical parameters of this space, and these data are often not in agreement. Archived measurement recordings from 1987 were recovered and found to include several balloon bursts. In 2015, a measurement session was carried out which included similar source-receiver pairs using both balloon bursts and swept sine stimuli. Comparisons between results from these two sessions show a significant decrease in reverberation time in the modern state. This change is attributed to the addition of carpet in several areas of the cathedral. A geometrical acoustics model of the cathedral was constructed and calibrated from the 2015 measurements. The effect of carpeting was investigated through simulati...
3D User Interfaces ( …, Mar 20, 2010
This paper presents the use of audio and haptic feedbacks to reduce the load of the visual channe... more This paper presents the use of audio and haptic feedbacks to reduce the load of the visual channel in interaction tasks within virtual environments. An examination is made regarding the exploitation of audio and/or haptic cues for the acquisition of a desired target in an environment containing multiple and obscured distractors. This study compares different ways of identifying and locating a specified target among others by the mean of either audio, haptic, or both feedbacks rendered simultaneously. The analysis of results ...
international conference on auditory display, Jul 1, 2015
In the absence of a well suited measure for quantifying binaural data variations, this study pres... more In the absence of a well suited measure for quantifying binaural data variations, this study presents the use of a global perceptual distance metric which can describe both HRTF as well as listener similarities. The metric is derived based on subjective evaluations of binaural renderings of a sound moving along predefined trajectories in the horizontal and median planes. Its characteristics and advantages in describing data distributions based on perceptually relevant attributes are discussed. In addition, the use of 24 HRTFs from two different databases of origin allows for an evaluation of the perceptual impact of some database-dependent characteristics on spatialization. The effectiveness of the experimental design as well as the correlation between the HRTF evaluations of the two plane trajectories are also discussed. This work was funded in part by the French FUI project BiLi ("Binaural Listening", www.bili-project.org, FUI-AAP14)
Proceedings of the 12th International Audio Mostly Conference on Augmented and Participatory Sound and Music Experiences, 2017
Our demonstration presents recent developments of the EVERTims project, an auralization framework... more Our demonstration presents recent developments of the EVERTims project, an auralization framework for virtual acoustics and real-time room acoustic simulation. The developments presented here concern the complete re-design of the scene graph editor unit, and the C++ implementation of a new spatial renderer based on the JUCE framework. EVERTims now functions as a Blender add-on to support real-time auralization of any 3D room model, both for its creation in Blender and its exploration in the Blender Game Engine. The EVERTims framework is published as open source software.
Virtual Reality (VR) reconstructions of architectural acoustics situations are used in the contex... more Virtual Reality (VR) reconstructions of architectural acoustics situations are used in the context of design and renovation projects for acoustically sensitive spaces and historical studies. In such studies, it is important to understand the impact of the visual rendering on auditory perceptions of the spaces concerned. For such a study, a virtual scenario was created, comprising the rendering of a theatrical performance, staged in a 3D visual model of an actual theater. The theater’s acoustics were numerically simulated using a geometrical acoustics model which was calibrated to in-situ measurements. The virtual scene was rendered on both a CAVE-light system and a Head Mounted Display (HMD) for various seating positions. Auralization, the audio rendering of the architectural acoustic simulation, was achieved using dynamic binaural processing of Ambisonic streams over headphones. Positionally matched and mismatched audio-visual configurations were presented in order to study the imp...
Proceedings of the …, Jun 24, 2008
This study presents an exploration task using interactive sonification to compare different son... more This study presents an exploration task using interactive sonification to compare different sonification mapping concepts. Based on the real application of protein-protein docking within the CoRSAIRe project («Combinaisons de Rendus Sensori-moteurs pour l'Analyse Immersive de Résultats», or Combination of sensori-motor rendering for the immersive analysis of results), an abstraction of the task was developed which simulates the basic concepts involved. Two conditions were evaluated, the inclusion or absence of spatialized ...
The Journal of the Acoustical Society of America, 2021
The Journal of the Acoustical Society of America, 2017
The Inter-aural Time Difference (ITD) is a fundamental cue for human sound localization. Over the... more The Inter-aural Time Difference (ITD) is a fundamental cue for human sound localization. Over the past decades, several methods have been proposed for its estimation from measured Head-Related Impulse Response (HRIR) data. Nevertheless, inter-method variations in ITD calculation have been found to exceed the known Just Noticeable Differences (JNDs), hence leading to possible perceptible artifacts in virtual binaural auditory scenes, even for cases when personalized HRIRs are being used. In the absence of an objective means for validating ITD estimations, this paper evaluates which methods lead to the most perceptually relevant results. A subjective lateralization study compared objective ITDs to perceptually driven inter-aural pure delay offsets. Results clearly indicate the first-onset Threshold detection method, using a low relative threshold of -30 dB, applied on 3 kHz low-pass filtered HRIRs as the most perceptually relevant procedure across various metrics. Alternative threshold values and methods ba...
The Journal of the Acoustical Society of America, 2017
As part of the 850-year anniversary of Notre-Dame cathedral, Paris, there was a special performan... more As part of the 850-year anniversary of Notre-Dame cathedral, Paris, there was a special performance of “La Vierge.” A close-mic recording of the concert was made by the Conservatoire de Paris. In an attempt to provide a new type of experience, a virtual recreation of the performance using these roughly 45 audio channels was made via auralization. A computational acoustic model was created and calibrated based on in-situ measurements for reverberation and clarity parameters. A perceptual study with omnidirectional source and binaural receiver validated the calibrated simulation for the tested subjective attributes of reverberation, clarity, source distance, tonal balance, coloration, plausibility, ASW, and LEV when compared to measured responses. Instrument directivity was included for each track's representative orchestral section based on published data. Higher-Order Ambisonic (3rd order) RIRs were generated for all source and receiver combinations using the CATT-Acoustic TUCT software. Virtual navigatio...
The Journal of the Acoustical Society of America, 2015
American Journal of Engineering and Applied Sciences, 2021
The main aim of the work is to assess physical parameters of forest woodchips and their impact on... more The main aim of the work is to assess physical parameters of forest woodchips and their impact on the prices achieved by the supplier in transactions with a power plant. During fragmentation of logging residue, high content of green matter and contaminants negatively impacts the quality parameters that serve as basis for settlements. The analysis concerns data on the main parameters-water content, fuel value, sulphur and ash content-from 252 days of deliveries of forest chips to a power plant. The deliveries were realised from forested areas on an average about 340 km from the plant. Average water content and the resultant fuel value of forest chips was within 27-47% and 8.7-12.9 GJ×Mg −1 (appropriately), respectively. They depend on the month in which they are delivered to the power plant. The threshold values for the above-mentioned parameters are set by the plant at a real level and the suppliers have no problems with meeting them. The parameter that is most frequently exceeded is ash content (11.5% of cases). The settlement system does not differentiate on the basis of the transport distance but gives possibility to lower the settlement price when the quality parameters are not met but provides no reward for deliveries with parameters better than the average ones. On the basis of results obtained, it was calculated that average annual settlement price is lower than the contract price by about 0.20 PLN×GJ −1 , which in case of the analysed company may translate into an average daily loss of about 700 PLN.
The Cathedrale Notre-Dame de Paris is amongst the most well-known worship spaces in the world. It... more The Cathedrale Notre-Dame de Paris is amongst the most well-known worship spaces in the world. Its large volume, in combination with a relatively bare stone construction and marble floor, leads to rather long reverberation times. The cathedral suffered from a significant fire in 2019, resulting in damage primarily to the roof and vaulted ceiling. Despite the notoriety of this space, there are few examples of published data on the acoustical parameters of this space, and these data do not agree. Archived measurement recordings from 1987 were recovered and found to include several balloon bursts. In 2015, a measurement session was carried out for a virtual reality project. Comparisons between results from these two sessions show a slight but significant decrease in reverberation time (8%) in the pre-fire state. Measurements were recently carried out on the construction site, 1 year since the fire. Compared to 2015 data, the reverberation time significantly decreased (20%). This paper ...
This article presents a case study of higher-order Ambisonics (HOA) for real-time sound field rep... more This article presents a case study of higher-order Ambisonics (HOA) for real-time sound field reproduction in a small room with a 157-loudspeaker array. It addresses a number of specific questions and practical issues on the system design and implementation, such as the reproduction room's acoustic, loudspeaker positioning and radiation patterns, distributed computing and audio channel synchronization, and in more general the achievable accuracy of sound field reproduction. In the current configuration of the system Ambisonics up to order n = 6 is applied and the decoders are rendered in parallel on a cluster of four computers. For this reason, synchronization and communication between the different computers becomes a challenging task for achieving a good system performance. The overall system latency and the inter-channel synchronicity have been measured using time-stretched pulse (TSP) signals. The measurement results have shown a maximum (unsigned) latency of 51 samples, which corresponds to t = 1.1 ms. It is obvious that the acoustic of the reproduction room has a strong effect on the accuracy of the Ambisonics sound field reproduction. To achieve semi-anechoic conditions sound absorption materials have been installed in the room. Finally, spatial filters have been applied to each individual loudspeaker to correct for different orientations with reference to the sweet spot. These filters have been derived from radiation pattern measurements in an anechoic chamber.
Considerations in characterising an almost anechoic room for interactive spatial audio reproducti... more Considerations in characterising an almost anechoic room for interactive spatial audio reproduction Densil Cabrera (1), Takuma Okamoto (2), Brian F.G. Katz (3), Markus Noisternig (4), Yukio Iwaya (2) and Yo-iti Suzuki (2)
The Journal of the Acoustical Society of America
This presentation will provide an overview of recent and ongoing studies regarding evaluations of... more This presentation will provide an overview of recent and ongoing studies regarding evaluations of sound fields using virtual loudspeaker binaural synthesis. Of specific interest is an identification of perceptual attributes affected by Head-Related Transfer Function (HRTF) choice beyond basic localization error and the sensitivity of listeners to head tracking with regards to latency and externalization judgments. A list of perceptual attributes, created using a Consensus Vocabulary Protocol elicitation method, and validated through listening tests, resulted in eight valid perceptual attributes for describing the perceptual dimensions affected by HRTF set variations. Employing prescribed head movements, sensitivity to head tracker latency showed small but significant differences between single and multichannel audio source scenes. A similar protocol was employed to comparing the sense of externalization as a function of head rotation with and without head tracking. In contrast to several previous studies,...
Notre-Dame de Paris is amongst the most well-known worship spaces in the world. Its large volume,... more Notre-Dame de Paris is amongst the most well-known worship spaces in the world. Its large volume, in combination with a relatively bare stone construction and marble floor, leads to rather long reverberation times. Despite the notoriety of this space, there are few examples of published data on the acoustical parameters of this space, and these data are often not in agreement. Archived measurement recordings from 1987 were recovered and found to include several balloon bursts. In 2015, a measurement session was carried out which included similar source-receiver pairs using both balloon bursts and swept sine stimuli. Comparisons between results from these two sessions show a significant decrease in reverberation time in the modern state. This change is attributed to the addition of carpet in several areas of the cathedral. A geometrical acoustics model of the cathedral was constructed and calibrated from the 2015 measurements. The effect of carpeting was investigated through simulati...
3D User Interfaces ( …, Mar 20, 2010
This paper presents the use of audio and haptic feedbacks to reduce the load of the visual channe... more This paper presents the use of audio and haptic feedbacks to reduce the load of the visual channel in interaction tasks within virtual environments. An examination is made regarding the exploitation of audio and/or haptic cues for the acquisition of a desired target in an environment containing multiple and obscured distractors. This study compares different ways of identifying and locating a specified target among others by the mean of either audio, haptic, or both feedbacks rendered simultaneously. The analysis of results ...