Publications

2024

1. AES

   

   Evaluation of Own Voice Perception while Using In-ear Headsets

   M. Takeuchi, J. Marozeau, R. F. Fela, and 2 more authors

   The AES 4th International Conference on Audio and Music Induced Hearing Disorders, Ålborg, Denmark. More Information can be found here , May 2024

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   Singing or speaking while using a headset or hearing aid can present significant challenges due to the occlusion effect, alongside variances in processing latency and auditory distortions inherent to these devices. Such challenges are particularly pronounced in activities like singing, where precise control over one’s vocal quality is paramount for performance. This study investigates the factors detrimental to the perceptual quality of one’s own voice when using in-ear headsets and how each factor influences one’s perception of self-voice. Prior literature reviews lead to occlusion, sidetone filters, latency, and distortion as the main factors. Twenty-three assessors participated in a subjective evaluation, which was followed by statistical data analysis. Further investigation was carried out through an assessor screening procedure and text analysis was performed on responses to collected open-ended questions. The study found that occlusion and distortion are the influential factors for the changes in self-voice perception, whereas latency is a determinant. Sidetone filtering becomes a significant factor when occlusion effects are minimized.

2023

1. JAES

   

   Comparison of Full Factorial and Optimal Experimental Design for Perceptual Evaluation of Audiovisual Quality

   R. F. Fela, N. Zacharov, and S. Forchhammer

   Journal of the Audio Engineering Society. More Information can be found here , Jan 2023

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   Perceptual evaluation of immersive audiovisual quality is often very labor-intensive and costly because numerous factors and factor levels are included in the experimental design. Therefore, the present study aims to reduce the required experimental effort by investigating the effectiveness of optimal experimental design (OED) compared to classical full factorial design (FFD) in the study using compressed omnidirectional video and ambisonic audio as examples. An FFD experiment was conducted and the results were used to simulate 12 OEDs consisting of D-optimal and I-optimal designs varying with replication and additional data points. The fraction of design space plot and the effect test based on the ordinary least-squares model were evaluated, and four OEDs were selected for a series of laboratory experiments. After demonstrating an insignificant difference between the simulation and experimental data, this study also showed that the differences in model performance between the experimental OEDs and FFD were insignificant, except for some interacting factors in the effect test. Finally, the performance of the I-optimal design with replicated points was shown to outperform that of the other designs. The results presented in this study open new possibilities for assessing perceptual quality in a much more efficient way.

2022

1. ICMEW

   

   Perceptual Evaluation on Audio-visual Dataset of 360 Content

   R. F. Fela, A. Pastor, P. Le Callet, and 3 more authors

   In 2022 IEEE International Conference on Multimedia and Expo Workshops (ICMEW). More Information can be found here , Jul 2022

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   To open up new possibilities to assess the multimodal perceptual quality of omnidirectional media formats, we proposed a novel open source 360 audiovisual (AV) quality dataset. The dataset consists of high-quality 360 video clips in equirectangular (ERP) format and higher-order ambisonic (4th order) along with the subjective scores. Three subjective quality experiments were conducted for audio, video, and AV with the procedures detailed in this paper. Using the data from subjective tests, we demonstrated that this dataset can be used to quantify perceived audio, video, and audiovisual quality. The diversity and discriminability of subjective scores were also analyzed. Finally, we investigated how our dataset correlates with various objective quality metrics of audio and video. Evidence from the results of this study implies that the proposed dataset can benefit future studies on multimodal quality evaluation of 360 content.

2. JAES

   

   Assessor Selection Process for Perceptual Quality Evaluation of 360 Audiovisual Content

   R. F. Fela, N. Zacharov, and S. Forchhammer

   Journal of Audio Engineering Society. More Information can be found here , Oct 2022

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   For accurate and detailed perceptual evaluation of compressed omnidirectional multimedia content, it is imperative for assessor panels to be qualified to obtain consistent and high-quality data. This work extends existing procedures for assessor selection in terms of scope (360? videos with high-order ambisonic), time efficiency, and analytical approach, as described in detail. The main selection procedures consisted of a basic audiovisual screening and three successive discrimination experiments for audio (listening), video (viewing), and audiovisual using a triangle test. Additionally, four factors influencing quality of experience, including the simulator sickness questionnaire, were evaluated and are discussed. After the selection process, a confirmatory study was conducted using three experiments (audio, video, and audiovisual) and based on a rating scale methodology to compare performance between rejected and selected assessors. The studies showed that (i) perceptual discriminations are influenced by the samples, the encoding parameters, and some quality of experience factors; (ii) the probability of symptom occurrence is considerably low, indicating that the proposed procedure is feasible; and (iii) the selected assessors performed better in discrimination than the rejected assessors, indicating the effectiveness of the proposed procedure.

2021

1. MMSP

   

   Perceptual Evaluation of 360 Audiovisual Quality and Machine Learning Predictions

   R. F. Fela, N. Zacharov, and S. Forchhammer

   In 2021 IEEE 23rd International Workshop on Multimedia Signal Processing (MMSP). More Information can be found here , Oct 2021

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   In an earlier study, we gathered perceptual evaluations of the audio, video, and audiovisual quality for 360 audiovisual content. This paper investigates perceived audiovisual quality prediction based on objective quality metrics and subjective scores of 360 video and spatial audio content. Thirteen objective video quality metrics and three objective audio quality metrics were evaluated for five stimuli for each coding parameter. Four regression-based machine learning models were trained and tested here, i.e., multiple linear regression, decision tree, random forest, and support vector machine. Each model was constructed using a combination of audio and video quality metrics and two cross-validation methods (k-Fold and Leave-One-Out) were investigated and produced 312 predictive models. The results indicate that the model based on the evaluation of VMAF and AMBIQUAL is better than other combinations of audio-video quality metric. In this study, support vector machine provides higher performance using k-Fold (PCC = 0.909, SROCC = 0.914, and RMSE = 0.416). These results can provide insights for the design of multimedia quality metrics and the development of predictive models for audiovisual omnidirectional media.

2020

1. QoMEX

   

   Towards a Perceived Audiovisual Quality Model for Immersive Content

   R. F. Fela, N. Zacharov, and S. Forchhammer

   In 2020 Twelfth International Conference on Quality of Multimedia Experience (QoMEX). More Information can be found here , May 2020

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   This paper studies the quality of multimedia content focusing on 360 video and ambisonic spatial audio reproduced using a head-mounted display and a multichannel loudspeaker setup. Encoding parameters following basic video quality test conditions for 360 videos were selected and a low-bitrate codec was used for the audio encoder. Three subjective experiments were performed for the audio, video, and audiovisual respectively. Peak signal-to-noise ratio and its variants for 360 videos were computed to obtain objective quality metrics and subsequently correlated with the subjective video scores. This study shows that a Cross-Format SPSNR-NN has a slightly higher linear and monotonic correlation over all video sequences. Based on the audiovisual model, a power model shows a highest correlation between test data and predicted scores. We concluded that to enable the development of superior predictive model, a high quality, critical, synchronized audiovisual database is required. Furthermore, comprehensive assessor training may be beneficial prior to the testing to improve the assessors’ discrimination ability particularly with respect to multichannel audio reproduction.

2019

1. BuildSim

   

   CFD Simulation in Naturally Ventilated Multi-Purpose Sports Hall: Effects to the Basketball and Badminton Matches

   M. Z. Afif, S. S. Utami, R. F. Fela, and 3 more authors

   In Building Simulation 2019, May 2019

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   This study investigates the thermal and ventilation performance of a naturally ventilated sports hall for basketball and badminton using computational fluid dynamics simulations. The focus is on achieving appropriate indoor air velocity conditions that satisfy thermal comfort requirements while not interfering with gameplay, particularly for badminton where air movement can affect shuttlecock trajectory.

2. BuildSim

   

   Effect of Façade Thickness on Daylight Performance in a Reference Office Building

   R. A. Mangkuto, R. F. Fela, and S. S. Utami

   Building Simulation, May 2019

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   This paper investigates how façade thickness affects daylight performance in office buildings. The study examines the relationship between window depth, solar shading, and indoor illumination levels using simulation and field measurements. Results show that façade thickness significantly impacts daylight distribution and glare control in tropical climates.

3. BuildSim

   

   The Effects of Orientation, Window Size, and Lighting Control to Climate-Based Daylight Performance and Lighting Energy Demand on Buildings in Tropical Area

   R. F. Fela, S. S. Utami, R. A. Mangkuto, and 2 more authors

   Building Simulation, May 2019

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   This study examines the combined effects of building orientation, window-to-wall ratio, and lighting control strategies on daylight performance and energy consumption in tropical climate buildings. Climate-based daylight modeling was used to evaluate multiple design configurations and their impact on visual comfort and energy efficiency.

4. AIP

   

   Study of Partition Walls to Minimize Leaking Sound in Counselling Rooms

   S. S. Utami, R. F. Fela, J. Sarwono, and 1 more author

   In AIP Conference Proceedings, May 2019

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   This study investigates the acoustic performance of different partition wall configurations to minimize sound leakage in counselling rooms, where speech privacy is critical. Various wall constructions and materials were tested using acoustic measurements and simulations to determine optimal sound insulation ratings.

5. AIP

   

   Prediction of Sound Insulation for Middle Class Apartment Based on Noise Site Analysis

   H. A. G. Barabah, S. S. Utami, H. R. Hapsari, and 3 more authors

   In AIP Conference Proceedings, May 2019

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   This paper presents a method for predicting sound insulation requirements in middle-class apartments based on site noise analysis. The study examines outdoor noise sources and proposes appropriate façade and partition constructions to achieve acceptable indoor acoustic comfort levels.

6. AIP

   

   Soundscape Study of an Urban Campus Park

   D. A. Puspagarini, S. S. Utami, A. S. Sudarsono, and 1 more author

   In AIP Conference Proceedings, May 2019

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   This study investigates the soundscape quality of an urban campus park through acoustic measurements and perceptual surveys. The research identifies key sound sources, their characteristics, and their contribution to overall acoustic comfort and user experience in the outdoor learning environment.

7. AIP

   

   Evaluation of Sonic Environment in Prospective Middle-class Apartment Building in Demak Regency

   H. R. Hapsari, S. S. Utami, H. A. G. Barabah, and 2 more authors

   In AIP Conference Proceedings, May 2019

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   This paper evaluates the acoustic environment of a proposed middle-class apartment building in Demak Regency, Indonesia. The study assesses potential noise sources, sound propagation, and recommends acoustic design strategies to ensure resident comfort and compliance with building acoustics standards.

2018

1. Book

   

   Menelusur Jejak Implementasi Konsep Bangunan Hijau dan Pintar di Kampus Biru

   S. S. Utami, R. F. Fela, R. J. Yanti, and 1 more author

   In Menelusur Jejak Implementasi Konsep Bangunan Hijau dan Pintar di Kampus Biru, May 2018

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   This book chapter traces the implementation of green and smart building concepts at the "Blue Campus" (Kampus Biru) of Universitas Gadjah Mada. It documents sustainable design strategies, energy efficiency measures, and intelligent building systems deployed across the campus.

2. ICSV

   

   Acoustics Survey to Predict Occupants Preferences of A Library

   S. S. Utami, R. F. Fela, J. Sarwono, and 1 more author

   In 25th International Congress on Sound and Vibration 2018, ICSV 2018, May 2018

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   This study conducts an acoustic survey to understand and predict user preferences in library spaces. The research examines background noise levels, speech intelligibility, and acoustic comfort through measurements and user surveys to inform acoustic design recommendations for library environments.

3. ICSV

   

   Hospital Soundscapes: Soundscapes Interventions in Intensive Care Unit

   S. S. Azzahra, I. R. N. Prasetiyo, J. Prasetiyo, and 2 more authors

   In 25th International Congress on Sound and Vibration 2018, May 2018

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   This paper investigates soundscape interventions in intensive care units to improve patient healing environments. The study examines current acoustic conditions, identifies disturbing sound sources, and proposes soundscape design strategies to reduce stress and support patient recovery.

4. ICSV

   

   A Pilot Study: How to Develop Auditory Virtual Reality for Pre-registered Nurses Education?

   Y. W. Fela, R. F. Fela, J. Sarwono, and 2 more authors

   In 25th International Congress on Sound and Vibration 2018, May 2018

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   This pilot study explores the development of auditory virtual reality systems for nursing education. The research investigates how spatial audio can enhance immersive training scenarios for pre-registered nurses, particularly for practicing clinical communication and emergency response in realistic soundscapes.

2017

1. INTER-NOISE

   

   Hospital Soundscape: Perception Analysis of Acoustics Environment in Intensive Care Unit

   I. R. N. Azzahra, R. F. Fela, J. Sarwono, and 2 more authors

   In INTER-NOISE and NOISE-CON Congress and Conference Proceedings, May 2017

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   This study analyzes perceptions of the acoustic environment in intensive care units through surveys and acoustic measurements. The research identifies key sound sources affecting patient and staff comfort, and examines the relationship between acoustic parameters and perceived soundscape quality.

2. INTER-NOISE

   

   Data Recording of Audio Stimulus for Continuing Nurse Training Using Auditory Virtual Environment

   R. F. Fela, J. Sarwono, S. S. Utami, and 2 more authors

   In INTER-NOISE and NOISE-CON Congress and Conference Proceedings, May 2017

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   This paper describes the methodology for recording audio stimuli used in auditory virtual environments for continuing nurse training. The study details the process of capturing realistic clinical soundscapes, including equipment alarms, patient sounds, and ambient hospital noise for immersive training applications.

3. INTER-NOISE

   

   Design Considerations for Improvement of Speech Intelligibility and Privacy in A Hospital Intensive Care Unit

   S. S. Utami, R. J. Yanti, J. Sarwono, and 2 more authors

   In INTER-NOISE and NOISE-CON Congress and Conference Proceedings, May 2017

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   This study presents design considerations for balancing speech intelligibility and privacy in hospital intensive care units. The research examines acoustic treatments and spatial configurations that enable clear communication among medical staff while protecting patient confidentiality.

2016

1. JNTETI

   

   Sinkronisasi Sensasi Pendengaran dan Visual di Dalam Dunia Simulasi Komputer

   S. Utami, M. Navvab, and R. Fela

   Jurnal Nasional Teknik Elektro dan Teknologi Informasi, May 2016

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   This paper discusses the synchronization of auditory and visual sensations in computer simulation environments. The study examines technical and perceptual aspects of audiovisual integration in virtual reality, focusing on latency, spatial consistency, and cross-modal interaction effects.

2014

1. Conference

   

   Analysis of Dome Geometry Effect on Acoustic Conditions of AR Fachruddin Mosque UMM Using CATT-Acoustic

   R. Ikhwanuddin, S. S. Utami, and R. F. Fela

   In Conference paper, May 2014

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   This study analyzes the effect of dome geometry on acoustic conditions in AR Fachruddin Mosque using CATT-Acoustic simulation software. The research examines reverberation time, sound distribution, and speech intelligibility under different dome configurations to optimize worship space acoustics.