Bibliography links: [Google scholar] [dblp]
2025
Zhou, X., Alexiou, E., Viola, I., and Cesar, P., 2025. PointPCA+: A full-reference Point Cloud Quality Assessment metric with PCA-based features. Signal Processing: Image Communication, 117262.
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Zhou, X.., Viola, I., Rossi, S., and Cesar, P., 2025. Comparison of Visual Saliency for Dynamic Point Cloud: Task-free vs. Task-dependent. IEEE Transactions on Visualization and Computer Graphics.
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Lee, S., Ahsan, M., Viola, I., and Cesar, P. 2025, March. User centric Requirements for Enhancing XR Use Cases with Machine Learning Capabilities. In IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VRW).
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Wylężek, K., Viola, I., Cesar, P., Jansen, J., Mulder, S., Eno, D., Koppelman, W., Franceschini, M., Rendina, M., and Bloemberg, N., 2025, March. Fashion Beneath the Skin - a Fashion Exhibition Experience in Social Virtual Reality. In IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VRW).
2024
Rossi, S., Viola, I., Toni, L., and Cesar, P., 2024. A Clustering Approach to Unveil User Similarities in 6-DoF Extended Reality Applications. ACM Transactions on Multimedia Computing, Communications and Applications.
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Alexiou, E., Zhou, X., Viola, I., and Cesar, P., 2024. PointPCA: Point cloud objective quality assessment using PCA-based descriptors. EURASIP Journal on Image and Video Processing.
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Cortés, C., Viola, I., Gutiérrez, J., Jansen, J., Subramanyam, S., Alexiou, E., Pérez, P., García, N., and César, P., 2024. Delay threshold for social interaction in volumetric eXtended Reality communication. ACM Transactions in Multimedia Computing, Communications, and Applications.
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Lee, S., Viola, I., Rossi, S., Guo, Z., Reimat, I., Lawicka, K., Striner, A., and Cesar, P., 2024. Designing and Evaluating a VR Lobby for a Socially Enriching Remote Opera Watching Experience. IEEE Transactions on Visualization and Computer Graphics.
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Zhou, X., Viola, I., Chen, Y., Pei, J., and Cesar, P. 2024, October. Deciphering Perceptual Quality in Colored Point Cloud: Prioritizing Geometry or Texture Distortion? In Proceedings of the 32nd ACM International Conference on Multimedia (MM’24). Association for Computing Machinery, New York, NY, USA.
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Jansen, J., Röggla, T., Rossi, S., Viola, I., and Cesar, P., 2024, October. Open-Sourcing VR2Gather: A Collaborative Social VR System for Adaptive Multi-Party Real Time Communication. In Proceedings of the 32nd ACM International Conference on Multimedia (ACM MM’24). Association for Computing Machinery, New York, NY, USA.
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Zhou, X., Viola, I., Yin, R., and Cesar, P. 2024, October. Visual-Saliency Guided Multi-modal Learning for No Reference Point Cloud Quality Assessment. In Proceedings of the 3rd International Workshop on Quality of Experience in Visual Multimedia Applications (QoEVMA ’24). Association for Computing Machinery, New York, NY, USA.
Pei, J., Viola, I., Huang, H., Wang, J., Ahsan, M., Ye, F., Yiming, J., Sai, Y., Wang, D., Chen, Z., Ren, P., and Cesar, P. 2024, August. Autonomous Workflow for Multimodal Fine-Grained Training Assistants Towards Mixed Reality. In The 62nd Annual Meeting of the Association for Computational Linguistics (ACL 2024).
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Lee, S., Viola, I., Singla, A., and Cesar, P., 2024, June. Communication Challenges between Clients and Producers of Immersive Media Applications: can Social XR help? In Proceedings of the 2024 ACM International Conference on Interactive Media Experiences (IMX ’24). Association for Computing Machinery, New York, NY, USA.
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Tliba, M., Zhou, X., Viola, I., Cesar, P., Chetouani, A., Valenzise, G., and Dufaux, F., 2024, June. Enhancing Immersive Experiences through 3D Point Cloud Analysis: A Novel Framework for Applying 2D Visual Saliency Models to 3D Point Clouds. In 2024 Sixteenth International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-6). IEEE.
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Nguyen, M., Vats, S., Zhou, X., Viola, I., Cesar, P., Timmerer, C., and Hellwagner, H., 2024, April. ComPEQ–MR: Compressed Point Cloud Dataset with Eye Tracking and Quality Assessment in Mixed Reality. In ACM Multimedia Systems Conference 2024 (MMSys ’24). Association for Computing Machinery, New York, NY, USA.
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Röggla, T., Shamma, D. A., Williamson, J. R., Viola, I., Rossi, S., and Cesar, P., 2024, April. A Platform for Collecting User Behaviour Data during Social VR Experiments Using Mozilla Hubs. In 16th International Workshop on Immersive Mixed and Virtual Environment Systems (MMVE ’24). Association for Computing Machinery, New York, NY, USA.
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2023
Viola, I., Jansen, J., Subramanyam, S., Reimat, I. and Cesar, P., 2023. VR2Gather: A collaborative social VR system for adaptive multi-party real-time communication. IEEE MultiMedia. [2023 IEEE Multimedia Best Paper Award]
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Singla, A., Wang, S., Göring, S., Rao, R.R.R., Viola, I., Cesar, P., and Raake, A, 2023, October. Subjective Quality Evaluation of Point Clouds using Remote Testing. In Proceedings of the 2nd International Workshop on Interactive eXtended Reality (IXR ’23). Association for Computing Machinery, New York, NY, USA.
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Zhou, X., Viola, I., Alexiou, E., Jansen, J., and Cesar, P., 2023, October. QAVA-DPC: Eye-Tracking Based Quality Assessment and Visual Attention Dataset for Dynamic Point Cloud in 6 DoF. In Proceedings of the IEEE International Symposium on Mixed and Augmented Reality (ISMAR). IEEE
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Zhou, X., Alexiou, E., Viola, I., and Cesar, P., 2023, October. PointPCA+: Extending PointPCA objective quality assessment metric. In 2023 IEEE International Conference on Image Processing (ICIP). IEEE
Rossi, S., Viola, I., Toni, L., and Cesar, P. 2023, June. Extending 3-DoF Metrics to Model User Behaviour Similarity in 6-DoF Immersive Applications. In Proceedings of the 14th ACM Multimedia Systems Conference (MMSys ’23). Association for Computing Machinery, New York, NY, USA.
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Smitskamp, S., Viola, I., and Cesar, P.. 2023, June. Evaluation of point cloud features for no-reference visual quality assessment. In 2023 Fifteenth International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-6). IEEE.
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2022
Viola, I., and Cesar, P., 2022. Volumetric video streaming. Current approaches and implementations. In Immersive Video Technologies, Giuseppe Valenzise, Martin Alain, Emin Zerman & Cagri Ozcinar (Eds.). Elsevier, 2022
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Alexiou, E., Nehmé, Y., Zerman, E., Viola, I., Lavoué, G., Ak, A., Smolic, A., Le Callet, P., and Cesar, P., 2022. Subjective and Objective Quality Assessment for Volumetric Video. In Immersive Video Technologies, Giuseppe Valenzise, Martin Alain, Emin Zerman & Cagri Ozcinar (Eds.). Elsevier, 2022
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Viola, I., Subramanyam, S., Li, J. and Cesar, P., 2022. On the impact of VR assessment on the Quality of Experience of Highly Realistic Digital Humans. Quality and User Experience, 7(1), pp.1-32.
Subramanyam, S., Viola, I., Jansen, J., Alexiou, E., Hanjalic, A. and Cesar, P., 2022, October. Evaluating the Impact of Tiled User-Adaptive Real-Time Point Cloud Streaming on VR Remote Communication. In Proceedings of the 30th ACM International Conference on Multimedia (MM ’22). Association for Computing Machinery, New York, NY, USA.
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Reimat, I., Mei, Y., Alexiou, E., Jansen, J., Li, J., Subramanyam, S., Viola, I., Oomen, J., and Cesar, P. 2022, October. Mediascape XR: A cultural heritage experience in Social VR. In Proceedings of the 30th ACM International Conference on Multimedia (MM ’22). Association for Computing Machinery, New York, NY, USA. [Best demo award]
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Rossi, S., Viola, I., and Cesar, P. 2022, October. Behavioural Analysis in a 6-DoF VR System: Influence of Content, Quality and User Disposition. In Proceedings of the 1st Workshop on Interactive eXtended Reality (IXR ’22). Association for Computing Machinery, New York, NY, USA.
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Cortés, C., Gutiérrez, J., Pérez, P., Viola, I., Cesar, P., and García, N. 2022, October. Impact of self-view latency on Quality of Experience: analysis of natural interaction in XR environments. In 2022 IEEE International Conference on Image Processing (ICIP). IEEE
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Subramanyam, S., Viola, I., Jansen, J., Alexiou, E., Hanjalic, A., and Cesar, P.. 2022, September. Subjective QoE Evaluation of User-Centered Adaptive Streaming of Dynamic Point Clouds. In 2022 Fourteenth International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-6). IEEE.
Xue, T., El Ali, A., Viola, I., Ding, G., and Cesar, P.. 2022, September. Designing Real-time, Continuous QoE Score Acquisition Techniques for HMD-based 360° VR Video Watching. In 2022 Fourteenth International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-6). IEEE.
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2021
Gutiérrez, J., et al. 2021. Subjective evaluation of visual quality and simulator sickness of short 360º videos: ITU-T Rec. P.919. In IEEE Transactions on Multimedia.
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Rossi, S., Viola, I., Toni, L., and Cesar, P.. 2021. A new Challenge: Behavioural analysis of 6-DoF user when consuming immersive media. In In 2021 IEEE International Conference on Image Processing (ICIP). IEEE
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Rossi, S., Viola, I., Jansen, J., Subramanyam, S., Toni, L., and Cesar, P.. 2021. Influence of Narrative Elements on User Behaviour in Photorealistic Social VR. In Proceedings of the International Workshop on Immersive Mixed and Virtual Environment Systems (MMVE '21). Association for Computing Machinery, New York, NY, USA.
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Reimat, I., Alexiou, E., Jansen, J., Viola, I., Subramanyam, S., and Cesar, P., 2021. CWIPC-SXR: Point Cloud dynamic human dataset for Social XR. In Proceedings of the 12th ACM Multimedia Systems Conference (pp. 300-306).
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2020
Viola, I. and Cesar, P., 2020. A reduced reference metric for visual quality evaluation of point cloud contents. In IEEE Signal Processing Letters.
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Subramanyam, S., Viola, I., Hanjalic, A. and Cesar, P., 2020. User-centered Adaptive Streaming of Dynamic Point Clouds with Low Complexity Tiling. In Proceedings of the 28th ACM international conference on Multimedia (MM ’20). Association for Computing Machinery, New York, NY, USA.
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Viola, I., Subramanyam, S. and Cesar, P., 2020, May. A color-based objective quality metric for point cloud contents. In 2020 Twelfth International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-6). IEEE.
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Subramanyam, S., Li, J., Viola, I. and Cesar, P., 2020, March. Comparing the quality of highly realistic digital humans in 3DoF and 6DoF: A volumetric video case study. In 2020 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) (pp. 127-136). IEEE.
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2019
Alexiou, E., Viola, I., Borges, T.M., Fonseca, T.A., de Queiroz, R.L. and Ebrahimi, T., 2019. A comprehensive study of the rate-distortion performance in MPEG point cloud compression. APSIPA Transactions on Signal and Information Processing, 8. [APSIPA Sadaoki Furui Prize Paper Award]
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Viola, I., Mulder, J., Simone, F. and Cesar, P., 2019, December. Temporal Interpolation of Dynamic Digital Humans using Convolutional Neural Networks. In 2019 IEEE International Conference on Artificial Intelligence and Virtual Reality (AIVR) (pp. 90-907). IEEE.
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Hériard-Dubreuil, B., Viola, I. and Ebrahimi, T., 2019, November. Light field compression using translation-assisted view estimation. In 2019 Picture Coding Symposium (PCS) (pp. 1-5). IEEE.
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Viola, I., Takahashi, K., Fujii, T. and Ebrahimi, T., 2019, September. Rendering-dependent compression and quality evaluation for light field contents. In Applications of Digital Image Processing XLII (Vol. 11137, p. 111371I). International Society for Optics and Photonics.
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Viola, I. and Ebrahimi, T., 2019, June. An in-depth analysis of single-image subjective quality assessment of light field contents. In 2019 Eleventh International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-6). IEEE.
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Viola, I., Takahashi, K., Fujii, T. and Ebrahimi, T., 2019, January. A comprehensive framework for visual quality assessment of light field tensor displays. Electronic Imaging, 2019(10), pp.310-1.
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2018
Viola, I., Maretic, H.P., Frossard, P. and Ebrahimi, T., 2018, September. A graph learning approach for light field image compression. In Applications of Digital Image Processing XLI (Vol. 10752, p. 107520E). International Society for Optics and Photonics.
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Willème, A., Mahmoudpour, S., Viola, I., Fliegel, K., Pospíšil, J., Ebrahimi, T., Schelkens, P., Descampe, A. and Macq, B., 2018, September. Overview of the JPEG XS core coding system subjective evaluations. In Applications of Digital Image Processing XLI (Vol. 10752, p. 107521M). International Society for Optics and Photonics.
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Upenik, E., Viola, I. and Ebrahimi, T., 2018, September. A rendering solution to display light field in virtual reality. In 2018 26th European Signal Processing Conference (EUSIPCO) (pp. 246-250). IEEE.
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Viola, I. and Ebrahimi, T., 2018, September. Comparison of Interactive Subjective Methodologies for Light Field Quality Evaluation. In 2018 26th European Signal Processing Conference (EUSIPCO) (pp. 1865-1869). IEEE.
Viola, I. and Ebrahimi, T., 2018, July. Quality assessment of compression solutions for ICIP 2017 Grand Challenge on light field image coding. In 2018 IEEE International Conference on Multimedia & Expo Workshops (ICMEW) (pp. 1-6). IEEE.
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Viola, I. and Ebrahimi, T., 2018, May. VALID: Visual quality assessment for light field images dataset. In 2018 Tenth International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-3). IEEE.
2017
Viola, I., ŘeÅ™ábek, M. and Ebrahimi, T., 2017. Comparison and evaluation of light field image coding approaches. IEEE Journal of selected topics in signal processing, 11(7), pp.1092-1106.
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Viola, I. and Ebrahimi, T., 2017, September. A new framework for interactive quality assessment with application to light field coding. In Applications of Digital Image Processing XL (Vol. 10396, p. 103961F). International Society for Optics and Photonics.
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Viola, I., ŘeÅ™ábek, M. and Ebrahimi, T., 2017, May. Impact of interactivity on the assessment of quality of experience for light field content. In 2017 Ninth International Conference on Quality of Multimedia Experience (QoMEX) (pp. 1-6). IEEE.
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2016
Viola, I., ŘeÅ™ábek, M., Bruylants, T., Schelkens, P., Pereira, F. and Ebrahimi, T., 2016, December. Objective and subjective evaluation of light field image compression algorithms. In 2016 Picture Coding Symposium (PCS) (pp. 1-5). IEEE.
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Viola, I., ŘeÅ™ábek, M. and Ebrahimi, T., 2016, September. A new approach to subjectively assess quality of plenoptic content. In Applications of Digital Image Processing XXXIX (Vol. 9971, p. 99710X). International Society for Optics and Photonics.
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