last update: February 2014

MPEG-4

Papers

• icmc00.ps.gz (94Kbyte)
• Title: Streaming Structured Audio
• Authors: Marek Claussen and Ludger Solbach
• Abstract: Structured Audio (SA) is an algorithmic low-bitrate coding standard for high-quality audio. Being a part of the MPEG-4 standard, it is expected to play an increasing role in multimedia applications such as computer games and interactive internet presentations. While first implementations have been developed for standard PCs using file-I/O, this paper is concerned with issues arising when the design goal is a streaming decoder running on an embedded multimedia processor with comparatively small external memory.
• Note: Paper presented at the ICMC 2000, Berlin

Multicomponent Acoustic Signal Separation

Dissertation

• Title: An Architecture for Robust Partial Tracking and Onset Localization in Single Channel Audio Signal Mixes

Papers

• aes99.ps.gz
  • Title: Partial Tone Tracking and Onset Localization in Single Channel Audio Signal Mixes
  • Author: Ludger Solbach
  • Abstract: A novel architecture for robust partial tracking and sound onset localization in audio signals is presented. Two time-frequency resolutions are evaluated in parallel, a broadband one for onset localization and a narrowband one for partial tracking. The fusion of the two, together with noise floor estimation and adaptive feedback cancellation, yields a robust and precise tool for audio signal analysis.
  • Note: Paper presented at the 106th AES convention, Munich, 1999
• icmc96.ps.gz (157 Kbyte)
  
• Title: Sound Onset Localization and Partial Tracking in Gaussian White Noise
• Authors: Ludger Solbach and Rolf Wöhrmann
• Abstract: In auditory scene analysis the detection of common partial onsets is an important clue for event formation. Our wavelet based approach for onset localization does not suffer from either smearing effects caused by windowing in the time domain nor from consistency problems caused by multiband level thresholding. Furthermore the method makes use of the beneficial effect of partial removal by adaptive signal cancelling. The results presented indicate that our approach is a promising basis for multicomponent acoustic signal separation.
• Note: Paper presented at the ICMC-96 in Hong Kong.
• Example: The original sound and its residual related to figures 3 and 4 (NeXT sound format).
• original sound (13.2 kByte)
• residual (14.8 kByte)
• ijcai95-casa_rev1.ps.gz (2.1 Mbyte)
• Title: The complex-valued continuous wavelet transform as a preprocessor for auditory scene analysis
• Authors: Ludger Solbach, Rolf Wöhrmann and Jörg Kliewer
• Abstract: In this paper we draw links between the widely used gammatone filter auditory model and wavelet theory. From the viewpoint of wavelet theory the benefit from linking these research fields is a fast method for the computation of a time-scale representation. From the viewpoint of auditory filtering the benefits are the existence of methods for the detection of signal singularities and for resynthesis. Our method has proved to be useful for the analysis of music pieces with a limited spectral overlap of the different signal components. It has been implemented for further research in automated music transcription and auditory source separation, but might also be of interest for sound synthesis systems based on the analysis and transformation of acoustic signals.
• Note: Revised reprint of the paper presented at the IJCAI-95 workshop on Computational Auditory Scene Analysis, Montral; to be published by Erlbaum Publishers in "Readings in Computational Auditory Scene Analysis", edited by Hiroshi Okuno and David Rosenthal; the authors wish to thank Erlbaum Publishers for their kind permission of reproduction.
• icmc95_rev1.ps.gz (1.4 Mbyte)
• Title: Preprocessing for the automated transcription of polyphonic music: linking wavelet theory and auditory filtering
• Authors: Rolf Wöhrmann and Ludger Solbach
• Abstract: In this paper a fast method for the calculation of a linear time-frequency distribution based on the gammatone filter auditory model is introduced as a preprocessing step for the automated transcription of music and auditory source separation. Examples show that this method has a promising potential for the analysis of music pieces with a limited spectral overlap of the different signal components.
• Note: Revised reprint of the paper presented at the ICMC95 in Banff, Canada.

Characterization of nonlinear systems by Volterra series

Papers

• volterra.ps.gz (46Kbyte)
• Title: The convergence of Volterra series for arbitrary nonlinear networks with two-terminal elements
• Authors: Tilo Ehlen, Karin Stamm and Ludger Solbach
• Abstract: The radius of convergence of the Volterra series representation of nonlinear networks with an arbitrary number of linear and nonlinear two-terminal elements is considered. By using a general system description via linear multiport theory and the method of nonlinear sources the Picard iteration is applied to calculate the Volterra series. The Banach fixpoint theorem is applied to a derived memoryless matrix equation which serves as a majorant to the iteration. The analysis of the resulting structure yields a simple expression for a secure estimation of the radius of convergence. An example is given for demonstration.
• Note: Karin Stamm and Tilo Ehlen are with RWTH Aachen. This is a preprint of a paper sent to IEEE transactions on circuits and systems, which is in the process of being reviewed.