Psychoacoustically Motivated Filter Bank Design for Real Time Audio Systems | Asger Hansen, Jonas Dahl
| | Abstract | DFT modulated filter banks are widely used in real time audio systems. Different prototype filter design methods have been proposed in literature. None of the methods use knowledge from psychoacoustic research to reduce the audibility of artefacts introduced by the filter bank. This thesis focus on the design of prototype filters for the DFT modulated filter bank with reduced audibility of artefacts by utilising a frequency domain masking model.
To obtain the masking model the artefacts introduced by the filter bank are quantified by a set of error functions and the psychoacoustic concepts to asses the audibility of the artefacts are discussed.
A quadratic optimisation method for prototype filter designs with and without the masking model is proposed and evaluated. The designs without the masking model shows good performance compared to classical methods while being more flexible. The designs with the masking model have poor performance compared to the designs without when evaluated by PESQ with a spectral subtraction algorithm applied in the filter bank.
The artefacts introduced by the designs with the masking model are analysed and it is concluded that the simplifications in the masking model imposed by the DFT modulated filter bank structure are too severe. Furthermore, the masking model do not account for artefacts in the modulation domain which are enhanced by applying the masking model. | | Type | Master's thesis [Academic thesis] | | Year | 2014 | | Publisher | Technical University of Denmark, Department of Applied Mathematics and Computer Science | | Address | Richard Petersens Plads, Building 324, DK-2800 Kgs. Lyngby, Denmark, compute@compute.dtu.dk | | Series | DTU Compute M.Sc.-2014 | | Note | DTU supervisors: Jan Larsen, Associate Professor, janla@dtu.dk, Department of Applied Mathematics and Computer Science, Technical University of Denmark, and Bastian Epp, Assistant Professor, Department of Electrical Engineering, Technical University of Denmark | | Electronic version(s) | [pdf] | | Publication link | http://www.compute.dtu.dk/English.aspx | | BibTeX data | [bibtex] | | IMM Group(s) | Intelligent Signal Processing |
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