Director and Research Scientist

Mathematics and Signal Processing in Acoustics

Machine Learning

Tel. +43 1 51581-2510

Email: peter.balazs(at)oeaw.ac.at

**Scientific IDs:**

orcid.org/0000-0003-4939-0831

Scopus Author ID: 8211873600

ResearcherID: E-3020-2010

https://scholar.google.at/

https://www.researchgate.net/

#### Academic background

Peter Balazs studied mathematics and physics at the University of Vienna. In 2001, he graduated with honors in mathematics and an M.Sc. thesis on "Polynomials over Groups" ("Polynome über Gruppen"). He successfully defended his PhD thesis and graduated (with distinction) in June 2005. His PhD thesis is titled, "Regular and Irregular Gabor Multiplier with Application to Psychoacoustic Masking," and can be downloaded here.

Peter Balazs has been part of the Institute since 1999. His PhD thesis was written at NuHaG, Faculty of Mathematics, University of Vienna. The cooperation formed during his thesis also resulted in him becoming a fellow of the HASSIP EU network. He joined the LATP, CMI and LMA, CNRS Marseille from November 2003 - April 2004 and in March, May and June of 2006. He also worked with the FYMA, UCL, Louvain-La-Neuve in August 2005.

In 2011 he has won the START prize, the national equivalent of the ERC starting grant in Austria, and therefore the most prestiguos award for youg scientists in Austria. In the same year he wrote his habilitation thesis "*New Concepts in Frame Theory Motivated by Acoustical Applications*".

In 2012 he was appointed as director of ARI.

#### Current research

Peter Balazs is interested in Time Frequency Analysis, Gabor Analysis, Numerics, Frame Theory, Signal Processing, Acoustics and Psychoacoustics.

He is now working on the START project '*Frames and Linear Operators for Acoustical Modeling and Parameter Estimation*', which aims at establishing frame theory as the mathematical backbone for acoustical modelling. For more details see here.

In particular, he currently works on the topic of frame multipliers, he has introduced in 2007, as well as on general frames theory and adaptive and adapted time-frequency transforms. For all those topics he works on the mathematicalö theory, but also poossible implementations and applications in acoustics.

### Projects

### Publications

## Publications

- Speckbacher M.; Bayer D.; Dahlke S.; Balazs P. (2017) The $alpha$-modulation transform: admissibility, coorbit theory and frames of compactly supported functions. Monatshefte fÜr Mathematik, Bd. 184, S. 133-169.
- Speckbacher M.; Balazs P. (2017) Reproducing pairs and Gabor systems at critical density. Journal of Mathematical Analysis and Applications, Bd. 455, S. 1072-1087.
- Stoeva D. T.; Balazs P. (2017) Commutative properties of invertible multipliers in relation to representation of their inverses. Proceedings of SampTA (2017). Tallinn S. 288-293.
- Zala S. M.; Reitschmidt D.; Noll A.; Balazs P.; Penn D. (2017) Sex-Dependent Modulation of Ultrasonic Vocalizations in House Mice (Mus musculus musculus). PLOS ONE, Bd. 12(12), S. e0188647.
- Zala S. M.; Reitschmidt D.; Noll A.; Balazs P.; Penn D. (2017) Automatic mouse ultrasound detector (A-MUD): A new tool for processing rodent vocalizations. PLOS ONE, Bd. 12(7), S. e0181200.
- Huang F.; Balazs P. (2017) Dictionary learning for pitch estimation in speech signals. 2017 IEEE 27th International Workshop on Machine Learning for Signal Processing (MLSP). S. 1-6.
- Pruša Z.; Rajmic P. (2017) Toward high-quality real-time signal reconstruction from STFT magnitude. IEEE Signal Processing Letters, Bd. 26, S. 892-896.
- Speckbacher M. (2017) Reproducing Pairs and Flexible Time-Frequency Representations. . Universität Wien, .
- Tabuchi H.; Laback B. (2017) Psychophysical and modeling approaches towards determining the cochlear phase response based on interaural time differences. . Bd. 141(6) S. 4314 ff.
- Necciari T.; Laback B.; Savel S.; Ystad S. l.; Balazs P.; Meunier S.; et al. (2016) Auditory Time-Frequency Masking for Spectrally and Temporally Maximally-Compact Stimuli. PLOS ONE, Bd. 11, S. 1-23.
- Balazs P.; Bayer D.; Jaillet F.; Sondergaard P. (2016) The Pole Behaviour of the Phase Derivative of the Short-Time Fourier Transform. Applied and Computational Harmonic Analysis, Bd. 30, S. 610-621.
- Stoeva D. T.; Balazs P. (2016) On the dual frame induced by an invertible frame multiplier. Sampling Theory in Signal and Image Processing, Bd. 15, S. 119-130.
- Balazs P.; Stoeva D. T. (2015) Representation of the inverse of a frame multiplier. J. Math. Anal. Appl., Bd. 422, S. 981-994.
- Holighaus N.; Wiesmeyr C.; Balazs P. (2015) Time-frequency representations for nonlinear frequency scales - Coorbit spaces and discretization. Inproceedings of SampTA 2015.
- Derrien O.; Necciari T.; Balazs P. (2015) A quasi-orthogonal, invertible, and perceptually relevant time-frequency transform for audio coding. Proceedings of the 23rd European Signal Processing Conference (EUSIPCO 2015). Nice, France S. 804-808.
- Stoeva D. T.; Balazs P. (2015) The dual frame induced by an invertible frame multiplier. Sampling Theory and Applications SampTA 2015. IEEE, S. 101-104.
- Speckbacher M.; Balazs P. (2015) Reproducing pairs and the continuous nonstationary Gabor transform on LCA groups. Journal of Physcis A: Mathematical and Theoretical, Bd. 48, S. 395201.
- Abreu L. D.; Balazs P.; de Gosson M.; Mouayn Z. (2015) Discrete coherent states for higher Landau levels. Annals of Physics, Bd. 363, S. 337 -353.
- Chardon G.; Necciari Th.; Balazs P. (2014) Perceptual matching pursuit with Gabor dictionaries and time-frequency masking. Proceedings of the 39th International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2014). Florence, Italy S. 3126-3130.
- Stoeva D. T.; Balazs P. (2014) Riesz Bases Multipliers. In: Concrete Operators, Spectral Theory, Operators in Harmonic Analysis and Approximation.. Birkhäuser, Heidelberg, New York, Dordrecht Bd. 236 S. 475-482.

### Additional information

## Additional information

#### Professional societies and activities

He is a student IEEE member since 2002, a regular member since 2005, a senior member since 2012. He is also a member of the AES, ÖMG and EMS .

#### Hobbies etc.

His hobbies are: music (playing the drums), baseball, games (especially role-playing games), and using the computer. You can view Peter Balazs's personal homepage here.

#### Past Research

He was the leader of the WWTF project Frame Multiplier: Theory and Application in Acoustics from 2008 - 2011. This project aimed to establish new results in the mathematic theory of frame multipliers - to integrate them into efficient digital signal processing algorithms, and to make them available for use in "real world" acoustic applications. This international, multi-disciplinary and team-oriented project has allowed P. Balazs to form the group 'Mathematics and Acoustical Signal Processing’ at the Acoustics Research Institute, in cooperation with NuHaG Vienna (Hans G. Feichtinger),* the group *Laboratoire PRISM of the LMA / CRNS Marseille (Richard Kronland-Martinet) and the Signal Processing Group of the LATP, CNRS Marseilles (Bruno Torrésani) as well as the FYMA, UCL, Louvain-La-Neuve (Jean-Pierre Antoine).

*Regular and irregular Gabor multiplier with application to psychoacoustic masking* was a focus of Balazs, even after finishing his PhD. and has developed into other projects like MulAc. With the Laboratoire PRISM, the Acoustics Research Institute has successfully implemented a WTZ-funded exchange project on "**Time-Frequency Representation and Perception**" for 2006 and 2007.

Balazs has also worked as a software developer at our Institute. When starting at the Institute in 1999, he was working on implementations in S_TOOLS-ST^{x} Macro & C++, documentation, user interface development, database structure concepts, and more. After finishing his studies, he has been delving deeper into the mathematical and theoretical background of signal processing.

His other projects include investigating the phase in acoustics, helping with the mathematical background in other projects, and some programming. He has also worked (and co-managed) in the project, "Vibrations in soils and liquids - Transform method for layers with random properties", a project of Dr. Ing. habil. Waubke funded by the FWF. Since June 2005 P. Balazs has been a permanent staff member of the Acoustics Research Institute.

His interests include discrete Gabor analysis and Gabor theory in the finite discrete setting, which is an area of high interest for any application. In 2006 he publshed a numerically efficient way to find an approximate dual window (a window that gives perfect reconstruction). He is using a special structure of Gabor analysis and synthesis via "Double Preconditioning for Gabor Frames".