Nikolaos Stefanakis, PhD

About me:

Since March 2018 I am an Assistant professor at the Department of Music Technology and Acoustics, at Hellenic Mediterranean University (HMU).

In February 2014 I joined the Institute of Computer Science of the Foundation for Research and Development – Hellas (FORTH) as a postdoc researcher.

In 2012 and 2013 I have served as a research fellow at the Institute of Mathematics in University of Potsdam, Germany. My project was concerned with the use of nonlinear dynamical models for the analysis and synthesis of percussive instruments.

From November 2010 till the end of 2011 I was a research fellow at the research centre of INRIA in Rennes, France.

The academic year 2009 – 2010 I worked at the Technical Educational Institute of Crete (TEI) where I was mainly occupied as a lecturer at the Department of Music Technology and Acoustics.

I finished my PhD at the School of Electrical and Computer Engineering in the National Technical University of Athens (NTUA) in 2008. During my PhD, I spent nine months as a Marie-Curie Fellow at the Center of Acoustic Technology in Technical University of Denmark.

I received my diploma degree in Mechanical Engineering from the School of Mechanical Engineering

of NTUA in 2002.

My research interests are in the fields of acoustics and audio signal processing. I am also active as a music composer and song writer (you can listen to some of my songs at www.soundcloud.com/asteritik).

Click here for a link to my full CV

Journal publications

Stefanakis Ν., Sarris J., Cambourakis G. and Jacobsen F., “Power output regularization in global sound equalization,” J. Acoust. Soc. Am. 123, pp 33-36 (2008).

http://orbit.dtu.dk/getResource?recordId=208788&objectId=1&versionId=1

Stefanakis Ν., Sarris J. and Cambourakis G., “Source placement for equalization in small enclosures,” J. Audio Eng. Soc. 56 (5), 357-371 (2008).

http://www.aes.org/e-lib/browse.cfm?elib=12632

Stefanakis Ν., Sarris J. and Jacobsen F., “Regularization in global sound equalization based on effort variation,” J. Acoust. Soc. Am. 126(2), 666-675 (2009).

http://orbit.dtu.dk/getResource?recordId=248311&objectId=1&versionId=1

Stefanakis Ν., Jacobsen F. and Sarris J., “Effort variation regularization in sound field reproduction,” J. Acoust. Soc. Am, 128(2), 740-750 (2010).

http://link.aip.org/link/?JASMAN/128/740/1

Stefanakis Ν., Abel M. and Bergner A., “Sound synthesis based on Ordinary Differential Equations,” J. Computer Music, 39(3), 46-58 (2015).

Stefanakis Ν., Pavlidi D. and Mouchtaris A., “Perpendicular cross-spectra fusion for sound source localization with a planar microphone array,” in IEEE Trans. on Audio, Speech and Language Processing, 25(9), 1517-1531 (2017).

Stefanakis Ν., Mastorakis Y., Alexandridis A. and Mouchtaris A., “Automating mixing of user-generated audio recordings from the same event,” accepted for publication in Journal of Audio Engineering Society (2019).

Stefanakis Ν., “Efficient implementation of superdirective beamforming in a half-space environment,” Journal of Acoustical Society of America, 145(3), (2019).

Perez-Lopez A. and Stefanakis N., “Analysis of spherical isotropic noise fields with an A-format tetrahedral microphone,” Journal of Acoustical Society of America, 146(4), (2019).

conference PUBLICATIONS

Stefanakis Ν. and Sarris J., “Sound field reproduction using the boundary element method,” in Proc. of 13th Int. Congress Sound Vib. (ICSV), Vienna, 2006.

Sarris J. C., Stefanakis N. J. and Cambourakis G. E., “Signal processing techniques for robust multichannel sound equalization,” 116th Convention of the Audio Engineering Society, Berlin, Germany, 2004, preprint 6087. http://www.aes.org/e-lib/browse.cfm?elib=12632

Sarris J., Stefanakis N. and Cambourakis G., “Sound equalization in a large region of a rectangular room” Acoustics 2004, Hellenic Institute of Acoustics, National Conference, Thessaloniki, September 2004.

Stefanakis Ν., Dalianis S., Karatzas T. and Cambourakis G., “Power output regularization in the active reproduction of sound fields in rooms,” in Proceedings of Acoustics’ 08, Paris, France.

http://intellagence.eu.com/acoustics2008/acoustics2008/cd1/data/articles/001704.pdf

Stefanakis N. and Zervas P., “A method for broad-band sound field reproduction in a large spatial region of a closed space,” Hellenic Institute of Acoustics, National Conference, Athens, October 2010.

Stefanakis. N., Marchal J., Emiya V., Bertin N., Gribonval. R. and Cervenka P., “Sparse underwater acoustic imaging: A case study,” in Proceedings of ICASSP 2012, Kyoto, Japan.

http://hal.inria.fr/hal-00661526

Stefanakis. N., Marchal J., Emiya V., Bertin N., Gribonval. R. and Cervenka P., “Sparse reconstruction techniques for near-field underwater acoustic imaging,” presented in Acoustics 2012, Nantes, France.

Stefanakis. N., Mastorakis Y. and Mouchtaris A., “Instantaneous detection and classification of impact sound: Turning simple objects into powerful musical control interfaces,” joint ICMC-SMC conference 2014, Athens, Greece.

Stefanakis. N. and Mouchtaris A., “Foreground suppression in capturing and reproduction of crowded acoustic environments,” in proceedings of ICASSP 2015, Brisbane, Australia.

Stefanakis. N. and Mouchtaris A., “A multi-sensor approach for real-time detection and classification of impact sounds” to be presented in EUSIPCO 2015, Nice, France.

Stefanakis. N., Chonianakis S. and Mouchtaris A., “Automatic matching and synchronization of user generated videos from a large scale sport event”, in proceedings of ICASSP, 2017.

Alexandridis A., Stefanakis N. and Mouchtaris A., “Towards wireless acoustic sensor networks for location estimation and counting of multiple speakers in real life conditions,” in proceedings of ICASSP, 2017.

Stefanakis. N., Viskadouros M. and Mouchtaris A., “A subjective evaluation on mixtures of crowdsourced audio recordings”, in proceedings of EUSIPCO, 2017.

Stefanakis. N. and Mouchtaris A., “Maximum Component Elimination in Mixing of User Generated Audio Recordings”, in proceedings of MMSP, 2017.

Stefanakis. N. and Mouchtaris A., “Normalization of partly overlapping recordings from the same event based on relative signal power”, in proceedings of ICASSP, 2018.

Stefanakis. N., Delikiaris-Manias S. and Mouchtaris A., “Acoustic beamforming in front of a reflective plane”, in proceedings of EUSIPCO, 2018.

Zervas P., Kouzoupis S. and Stefanakis. N., “Evaluating a low-cost acoustic sensor for smart environments applications”, Hellenic Institute of Acoustics, National Conference, Patra, October 2018.

Tzagkarakis C., Stefanakis N. and Tzagkarakis G., “Impact Sounds Classification for Interactive Applications via Discriminative Dictionary Learning”, in proceedings of EUSIPCO, 2019.

BOOK CHAPTERS

Alexandridis A., Pavlidi D., Stefanakis N. and Mouchtaris A., “Applications of TF-domain parametric spatial audio techniques in teleconferencing and remote presence,” in Parametric time-frequency-domain spatial audio, Pulkki V., Delikaris-Manias S. and Politis A., Eds, Wiley (in press).

PATENTS

Abel M., Bergner A., Stefanakis N. and Ahnert K., “Method and system for synthetic modeling of a sound signal,” European Patent Office, EP 3012832 A1, 2016.

http://google.com/patents/EP3012832A1?cl=zh

Stefanakis N. and Mouchtaris A., “Direction of arrival estimation and sound source enhancement in the presence of a reflective surface, apparatuses, methods, and systems”, USPTO Non-Provisional Application No. 15/276,785, filed September 26, 2016 (accepted).

Stefanakis N. and Mouchtaris A., “Capturing and reproducing spatial sound apparatuses, methods and systems”, USPTO Non-Provisional Application No. 15/183,554, filed June 15, 2016 (accepted).

Stefanakis N. and Mouchtaris A., “Foreground signal suppression apparatuses, Methods, and Systems”, USPTO Non-Provisional Application No. 15/183,573, filed June 15, 2016 (accepted).

Stefanakis N. and Mouchtaris A., “Direction of arrival (DOA) estimation apparatuses, methods and systems”, USPTO Non-Provisional Application No. 15/183,538, filed June 15, 2016 (accepted).

PHD Thesis

Stefanakis N, “Improvements in the multiple-point method during equalization and sound field reproduction in closed spaces”, PhD Thesis, School of Electrical and Computer Engineering, National Technical University of Athens, 2008.