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

- Stoeva, D. T.; Balazs, P. (2020) A survey on the unconditional convergence and the invertibility of multipliers with implementation. In: Casey, S. D.; Okoudjou, K.; Robinson, M.; Sadler, B. (Hrsg.), Sampling - Theory and Applications. Applied and Numerical Harmonic Analysis; Cham: Birkhäuser, S. 169 - 192.
- Balazs, P.; Holighaus, N. (2020) LTFAT - Die Zeit-Frequenz Toolbox., Jubiläumstagungsband DAGA 2020.
- Shamsabadi, M.; Arefijamaal, A.; Balazs, P. (2020) The invertibility of U-fusion cross Gram matrices of operators. Mediterranean Journal of Mathematics.
- Speckbacher, M.; Balazs, P. (2020) Frames, their relatives and reproducing kernel Hilbert spaces. J. Phys. A: Math. Theor., Bd. 53, S. 015204.
- Rajbamshi, S.; Tauboeck, G.; Balazs, P.; Abreu, L. D. (2020) Method for Signal Processing.
- Balazs, P.; Harbrecht, H. (2019) Frames for the solution of operator in Hilbert spaces with fixed dual pairing. Numerical Functional Analysis and Optimization, Bd. 40, S. 65-84.
- Balazs, P.; Heineken.; S. (2019) An Operator Based Approach to Irregular Frames of Translates. Mathematics as part of the Special Issue Harmonic Analysis, Bd. 7, S. 449.
- Balazs, P.; Shamsabadi, M.; Arefijamaal, A.; Rahimi, A. (2019) U-cross Gram matrices and their invertibility. Journal of Mathematical Analysis and Applications, Bd. 476, S. 367-390.
- Abbasi, R.; Balazs, P.; Noll, A. Nicolakis, D.; Adelaide Marconi, M.; Zala, S. M. et al. [..] (2019) Applying Convolutional Neural Networks to the Analysis of Mouse Ultrasonic Vocalizations., Proceedings of ICA 2019.
- Balazs, P.; Gröchenig, K.; Speckbacher, M. (2019) Kernel Theorems in Coorbit Theory. Transactions of the American Mathematical Society.
- Tauböck, G.; Rajbamshi, S.; Balazs, P.; Abreu, D. (2019) Random Gabor Multipliers and Compressive Sensing., Proceedings of SampTA 2019 (13th International conference on Sampling Theory and Applications).
- Haider, D.; Balazs, P. (2019) Extraction of Rhythmical Features with the Gabor Scattering Transform., Proceedings of the 14th International Symposium on Computer Music Multidisciplinary Research (CMMR), Marseille, France, Oct. 14-18, S. 916-923.
- Huang, F.; Balazs, P. (2019) Harmonic-aligned Frame Mask Based on Non-stationary Gabor Transform with Application to Content-dependent Speaker Comparison., Interspeech 2019.
- Rajbamshi, S.; Balazs, P.; Holighaus, N. (2019) Adhoc method to Invert the Reassigned Time-Frequency Representation., Proceedings of the 23rd International Congress on Acoustics, S. 2789 - 2796.
- Rajbamshi, S., Tauböck, G., Balazs, P., Abreu, L. D. (2019) Random Gabor Multipliers for Compressive Sensing: A Simulation Study., Proceedings of the EUSIPCO 2019.
- Necciari, T, Holighaus, N.; Balazs, P.; Pruša, Z.; Majdak, P.; Derrien, O. (2018) Audlet Filter Banks: A Versatile Analysis/Synthesis Framework using Auditory Frequency Scales. Applied Sciences, Bd. 8, S. 96-117.
- Perraudin, N.; Holighaus, N.; Majdak, P.; Balazs, P. (2018) Inpainting of Long Audio Segments with Similarity Graphs. IEEE/ACM Transactions on Audio, Speech, and Language Processing, Bd. 26, S. 1079-1090.
- Perraudin, N.; Holighaus, N.; Sondergaard, P. L.; Balazs, P. (2018) Designing Gabor windows using convex optimization. Applied Mathematics and Computation, Bd. 330, S. 266 - 287.
- Balazs, P. (2018) Frame Multipliers - a mathematical background for time-variant filters and auditory scene analysis., Fortschritte in der Akustik (DAGA 2018).
- Holighaus, N.; Wiesmeyr, C.; Balazs, P. (2018) Continuous warped time-frequency representations - Coorbit spaces and discretization. Applied and Computational Harmonic Analysis.

### 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".