Leader: Ing. Jiří Schimmel, Ph.D.

Acoustic signal processing

About group

The group has achieved the greatest success in the design and implementation of digital sound effects, real-time signal processors and personal computers on Windows and MacOS. In this area there is an extensive cooperation with foreign companies. The lessons learned are now being used to develop algorithms and software for analyzing audio signals and acoustic fields in real time. The group is also developing a new method for suppressing musical noise in audio signals.

In cooperation with industry a hardware platform and software of a modular multi-channel digital sound system were created allowing the configuration, implementation and management of algorithms for digital processing of audio signals in real time via the Internet. This system is modified for use in embedded devices, and its own audio interface with high-quality sound parameters is currently being developed.

In the field of sound analysis, we focus on measuring and evaluating the noise of equipment and environment, identification of noise sources, visualization of sound fields, measurement of electroacoustic transducers, measurement of acoustic spaces, measuring audio and telecommunication equipment, etc. An anechoic chamber and a special laboratory with modified acoustic reverberation are available for these measurements.

Companies and universities we are cooperating with

Relation to the study subjects

  • Signals and systems analysis (BASS)
  • Electroacoustics (BELA)
  • Studioengineering (BSHE)
  • Digital filters (BCIF)
  • Digital signal processing (MCSI)
  • Computers and peripheral devices (MNAV)
  • Graphic and multimedia processors (MGMP)
  • Digital audio signal processing (MCAS)

Information for potential applicants

The group admits new members from among potential applicants and requires experience in computer modeling, working with Matlab or similar, at least a basic knowledge of object-oriented programming and programming in Windows, MacOS or Linux, a good knowledge of the theory of signals and systems, a basic knowledge in the field of acoustics and sound perception by humans. Cooperation is possible in the areas of processing audio signals in real time on personal computers, digital sound effects, and the analysis and synthesis of sound fields.

Important publications

MAČÁK, J., SCHIMMEL, J.: Real-Time Guitar Preamp Simulation Using Modified Block-wise Method and Approximations. EURASIP Journal on Advances in Signal Processing. 2011. ISSN 1687-6172.

SCHIMMEL, J.: Subjective Evaluation of Latency in Real-Time Audio Signal Processing Systems. In Proceedings of 33rd International Conference on Telecommunications and Signal Processing – TSP 2010. Budapest, Asszisztencia Szervezo Kft. 2010. pp. 74-77. ISBN 978-963-88981-0-4.

SCHIMMEL, J.: Performance Analysis of Parallel Signal Processing Algorithms in Audio Mixing Systems. In Proceedings of The Ninth International Conference on Networks ICN 2010. IEEE Computer Society. 2010. p. 61 – 64. ISBN 978-0-7695-3979-9.

SCHIMMEL, J., MIŠUREC, J.: Characteristics of Broken-Line Approximation and Its Use in Distortion Audio Effects. In Proceedings of the 10th International Conference on Digital Audio Effects Proceedings. Bordeaux, France: LaBRI-University of Bordeaux, 2007. pp. 161-164. ISBN 978-88-901479-1-3.

SCHIMMEL, J.: Using Parallel Signal Processing in Real-Time Audio Matrix Systems. WSEAS Transactions on Computers. 2010. 9(2). pp.174-176. ISSN 1109-2750.

SCHIMMEL, J., TRZOS, M.: Digitální zvukové efekty pro Surround Sound. Elektrorevue – Internetový časopis (http://www.elektrorevue.cz). 2010(2). pp. 1-10. ISSN 1213-1539.

RÁŠO, O., BALÍK, M., KOUŘIL, J.: Origin and Suppression of Musical Tonal Noise in Thresholding Methods. In Proceedings of the 33rd International Conference on Telecommunications and Signal Processing. 2010. pp. 84-89. ISBN 978-963-88981-0-4.

BALÍK, M.: Optimized Structure for Multichannel Digital Reverberation. WSEAS Transactions on Acoustics and Music. 2004(1). pp. 62-68. ISSN 1109-9577.

RÁŠO, O., BALÍK, M.: Method for Suppression of Musical Tonal Noise in Audio Signals. Elektrorevue – Internetový časopis (http://www.elektrorevue.cz). 2010. 2010(11). pp. 1 – 6. ISSN 1213-1539.

SYSEL, P., MIŠUREC, J.: Estimation of Power Spectral Density using Wavelet Thresholding. In WSEAS Applied Informatics & Communications. 2008(1). pp. 207 – 211. ISBN 978-960-474-035-2.

SMÉKAL, Z., SYSEL, P.: Enhanced estimation of power spectral density of noise. Personal Wireless Communications. Springer, 2007. Vol. 245, pp. 521-531. ISSN 1571-5736.

SMÉKAL, Z., SYSEL, P.: Single-Channel Noise Suppression by Wavelets in Spectral Domain. Lecture Notes in Computer Science (IF 0,513). 2007. No 4775. pp. 150-164. ISSN 0302-9743.

SYSEL, P.: Statistical Based Voice Activity Detector. In Proceedings of International Conference on Signals and Electronic Systems. Lodz, Poland, Lodz. 2006. pp. 687-689. ISBN 83-921172-5-5.