Simple spectral subtraction method enhances speech intelligibility in noise for cochlear implant listeners

  • Matthias Leimeister Fraunhofer Institute for Digital Media Technology IDMT, Ilmenau, Germany Institute for Media Technology, Faculty of Electrical Engineering and Information Technology, Ilmenau University of Technology, Ilmenau, Germany
  • Csanád Egervári Fraunhofer Institute for Digital Media Technology IDMT, Ilmenau, Germany Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
  • Felix Kuhnke Fraunhofer Institute for Digital Media Technology IDMT, Ilmenau, Germany Institute for Media Technology, Faculty of Electrical Engineering and Information Technology, Ilmenau University of Technology, Ilmenau, Germany
  • Anja Chilian Fraunhofer Institute for Digital Media Technology IDMT, Ilmenau, Germany Institute of Biomedical Engineering and Informatics, Faculty of Computer Science and Automation, Ilmenau University of Technology, Ilmenau, Germany Cochlear-Implant Rehabilitationszentrum Thüringen, Erfurt, Germany
  • Charlott Voigt Fraunhofer Institute for Digital Media Technology IDMT, Ilmenau, Germany
  • Tamás Harczos Fraunhofer Institute for Digital Media Technology IDMT, Ilmenau, Germany Institute for Media Technology, Faculty of Electrical Engineering and Information Technology, Ilmenau University of Technology, Ilmenau, Germany Cochlear-Implant Rehabilitationszentrum Thüringen, Erfurt, Germany

Abstract

It has been demonstrated that while clean speech is well intelligible by most cochlear implant (CI) listeners, noise quickly degrades speech intelligibility. To remedy the situation, CI manufacturers integrate noise reduction (NR) algorithms (often using multiple microphones) in their CI processors, and they report that CI users benefit from this measure. We have implemented a single-microphone NR scheme based on spectral subtraction with minimum statistics to see if such a simple algorithm can also effectively increase speech intelligibility in noise. We measured speech reception thresholds using both speech-shaped and car noise in 5 CI users and 23 normal-hearing listeners. For the latter group, CI hearing was acoustically simulated. In case of the CI users, the performance of the proposed NR algorithm was also compared to that of the CI processor’s built-in one. Our NR algorithm enhances intelligibility greatly in combination with the acoustic simulation regardless of the noise type; these effects are highly significant. For the CI users, trends agree with the above finding (for both the proposed and the built-in NR algorithms), however, due to low sample number, these differences did not reach statistical significance. We conclude that simple spectral subtraction can enhance speech intelligibility in noise for CI listeners and may even keep up with proprietary NR algorithms.

References

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Published
2015-12-15
How to Cite
LEIMEISTER, Matthias et al. Simple spectral subtraction method enhances speech intelligibility in noise for cochlear implant listeners. Proceedings of the International Symposium on Auditory and Audiological Research, [S.l.], v. 5, p. 325-332, dec. 2015. Available at: <https://proceedings.isaar.eu/index.php/isaarproc/article/view/2015-38>. Date accessed: 20 nov. 2017.
Section
2015/5. Compensation strategies for rehabilitation with cochlear implants