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Walter Kellermann

33 accepted papers

2023

Exploiting Spatial Information with the Informed Complex-Valued Spatial Autoencoder for Target Speaker Extraction

ICASSP 2023accepted

In conventional multichannel audio signal enhancement, spatial and spectral filtering are often performed sequentially. In contrast, it has been shown that for neural spatial filtering a joint approach of spectro-spatial filtering is more beneficial. In this contribution, we investigate the spatial…

Cited by 0SourceScholar
2023

Spatially Informed Independent vector analysis for Source Extraction based on the convolutive Transfer Function Model

ICASSP 2023accepted

Spatial information can help improve source separation performance. Numerous spatially informed source extraction methods based on the independent vector analysis (IVA) have been developed, which can achieve reasonably good performance in non- or weakly reverberant environments. However, the perform…

Cited by 0SourceScholar
2023

Switching Kronecker Product Linear Filtering for Multispeaker Adaptive Speech Dereverberation

ICASSP 2023accepted

Dereverberation, a process to mitigate or eliminate the reverberation effect, plays an important role in hands-free speech communication and human-machine interfaces. Tremendous efforts have been devoted to this problem and various methods have been developed over the last three decades. Those metho…

Cited by 0SourceScholar
2022

End-To-End Deep Learning-Based Adaptation Control for Frequency-Domain Adaptive System Identification

ICASSP 2022accepted

We present a novel end-to-end deep learning-based adaptation control algorithm for frequency-domain adaptive system identification. The proposed method exploits a deep neural network to map observed signal features to corresponding step-sizes which control the filter adaptation. The parameters of th…

Cited by 0SourceScholar
2022

Manifold Learning-Supported Estimation of Relative Transfer Functions For Spatial Filtering

ICASSP 2022accepted

Many spatial filtering algorithms used for voice capture in, e.g., teleconferencing applications, can benefit from or even rely on knowledge of Relative Transfer Functions (RTFs). Accordingly, many RTF estimators have been proposed which, however, suffer from performance degradation under acoustical…

Cited by 0SourceScholar
2021

Combining Adaptive Filtering And Complex-Valued Deep Postfiltering For Acoustic Echo Cancellation

ICASSP 2021accepted

In this contribution, we introduce a novel approach to noise-robust acoustic echo cancellation employing a complex-valued Deep Neural Network (DNN) for postfiltering. In a first step, early linear echo components are removed using a double-talk robust adaptive filter. The residual signal is subseque…

Cited by 0SourceScholar
2021

Effective Rank-Based Estimation of the Coherent-to-Diffuse Power Ratio

ICASSP 2021accepted

Many algorithms for speech dereverberation and noise reduction rely on an estimate of the coherent-to-diffuse power ratio (CDR). Such systems typically operate in very diverse acoustic conditions, and CDR estimators relying on very weak model assumptions about the acoustic sound field of the desired…

Cited by 0SourceScholar
2021

Misalignment Recognition in Acoustic Sensor Networks Using a Semi-Supervised Source Estimation Method and Markov Random Fields

ICASSP 2021accepted

In this paper, we consider the problem of acoustic source localization by acoustic sensor networks (ASNs) using a promising, learning-based technique that adapts to the acoustic environment. In particular, we look at the scenario when a node in the ASN is displaced from its position during training.…

Cited by 0SourceScholar
2021

Network-Aware Optimal Microphone Channel Selection in Wireless Acoustic Sensor Networks

ICASSP 2021accepted

To address the vital problem of selecting the most useful microphones in wireless acoustic sensor networks, this paper proposes a novel, general-purpose approach that accounts for both acoustic and network aspects and remains application-agnostic for broad applicability. The inter-channel correlatio…

Cited by 0SourceScholar
2021

Noise-Robust Adaptation Control for Supervised Acoustic System Identification Exploiting a Noise Dictionary

ICASSP 2021accepted

We present a noise-robust adaptation control strategy for block-online supervised acoustic system identification by exploiting a noise dictionary. The proposed algorithm takes advantage of the pronounced spectral structure which characterizes many types of interfering noise signals. We model the noi…

Cited by 0SourceScholar
2020

Efficient Multichannel Nonlinear Acoustic Echo Cancellation Based on a Cooperative Strategy

ICASSP 2020accepted

While a common approach to address nonlinear distortions, emitted by multiple loudspeakers and observed by multiple microphones, is to use post-filtering techniques, this paper proposes a cooperative strategy to rather model and then cancel such distortions. In this approach, the overall problem of…

Cited by 0SourceScholar
2019

Localization of an Unknown Number of Speakers in Adverse Acoustic Conditions Using Reliability Information and Diarization

ICASSP 2019accepted

This paper investigates localization of an arbitrary number of simultaneously active speakers in an acoustic enclosure. We propose an algorithm capable of estimating the number of speakers, using reliability information to obtain robust estimation results in adverse acoustic scenarios and estimating…

Cited by 0SourceScholar
2019

Neural Networks Sequential Training Using Variational Gaussian Particle Filter

ICASSP 2019accepted

In this paper, we propose a sequential training algorithm for feed-forward neural networks based on particle filtering. The proposed algorithm uses variational learning to tailor a proposal density by minimizing the variational energy. This density is then incorporated into the Gaussian particle fil…

Cited by 0SourceScholar
2018

A Novel Ego-Noise Suppression Algorithm for Acoustic Signal Enhancement in Autonomous Systems

ICASSP 2018accepted

The use of autonomous systems (ASs), such as humanoid robots, drones or self-driving vehicles, has expanded significantly in recent years. For such systems, acoustic scene analysis can provide useful information about the environment and supports the AS to react appropriately. However, compared to m…

Cited by 0SourceScholar
2018

Learning-Based Acoustic Source-Microphone Distance Estimation Using the Coherent-to-Diffuse Power Ratio

ICASSP 2018accepted

We propose a method for estimating the distance between a sound source and a pair of recording microphones. The developed algorithm operates in the short-time Fourier transform domain and is based on estimates of the coherent-to-diffuse power ratio, which provides a measure for the amount of reverbe…

Cited by 0SourceScholar
2018

Nonlinear Acoustic Echo Cancellation Using Elitist Resampling Particle Filter

ICASSP 2018accepted

This paper considers an effective method for nonlinear acoustic echo cancellation (NL-AEC). More specifically, we model the nonlinear echo path by a latent state vector capturing the coefficients of a memoryless processor and a linear finite impulse response filter. To estimate the posterior probabi…

Cited by 0SourceScholar
2017

Online environmental adaptation of CNN-based acoustic models using spatial diffuseness features

ICASSP 2017accepted

We propose a new concept for adapting CNN-based acoustic models using spatial diffuseness features as auxiliary information about the acoustic environment: the spatial diffuseness features are simultaneously employed as acoustic-model input features and to estimate environmental cues for context ada…

Cited by 0SourceScholar
2017

Online secondary path modelling in wave-domain active noise control

ICASSP 2017accepted

The performance of an ANC system largely depends on the availability of an accurate secondary path model. This is however a major challenge in multichannel ANC where the computational complexity increases significantly with the number of secondary sources and error sensors. This paper proposes wave-…

Cited by 0SourceScholar
2016

A new uncertainty decoding scheme for DNN-HMM hybrid systems with multichannel speech enhancement

ICASSP 2016accepted

Uncertainty decoding combines a probabilistic feature description with the acoustic model of a speech recognition system. For DNN-HMM hybrid systems, this can be realized by averaging the DNN outputs produced by a finite set of feature samples (drawn from an estimated probability distribution). In t…

Cited by 0SourceScholar
2016

Ego-noise reduction using a motor data-guided multichannel dictionary

IROS 2016poster

We address the problem of ego-noise reduction, i.e., suppressing the noise a robot causes by its own motions. Such noise degrades the recorded microphone signal massively such that the robot's auditory capabilities suffer. To suppress it, it is intuitive to use also motor data, since it provides add…

Cited by 21SourceScholar
2016

Generalized wave-domain transforms for listening room equalization with azimuthally irregularly spaced loudspeaker arrays

ICASSP 2016accepted

In reverberant environments, Listening Room Equalization (LRE) by pre-filtering of loudspeaker signals is highly desirable for premium sound reproduction systems with a high number of loudspeakers. In this contribution, the efficient concept of LRE by wave-domain adaptive filtering is extended by de…

Cited by 0SourceScholar
2016

Higher-order listening room compensation with additive compensation signals

ICASSP 2016accepted

The performance of sound reproduction systems for spatial audio is impaired by time-variant, reverberant listening environments. To tackle this issue, the Loudspeaker-Enclosure-Microphone System (LEMS) between the loudspeakers and reference microphones in the listening environment can be identified…

Cited by 0SourceScholar
2015

Enhanced robot audition by dynamic acoustic sensing in moving humanoids

ICASSP 2015accepted

Auditory systems of humanoid robots usually acquire the surrounding sound field by means of microphone arrays. These arrays can undergo motion related to the robot's activity. The conventional approach to dealing with this motion is to stop the robot during sound acquisition. This approach avoids ch…

Cited by 0SourceScholar
2015

Phase-optimized K-SVD for signal extraction from underdetermined multichannel sparse mixtures

ICASSP 2015accepted

We propose a novel sparse representation for heavily underdetermined multichannel sound mixtures, i.e., with much more sources than microphones. The proposed approach operates in the complex Fourier domain, thus preserving spatial characteristics carried by phase differences. We derive a generalizat…

Cited by 0SourceScholar
2015

Spatial diffuseness features for DNN-based speech recognition in noisy and reverberant environments

ICASSP 2015accepted

We propose a spatial diffuseness feature for deep neural network (DNN)-based automatic speech recognition to improve recognition accuracy in reverberant and noisy environments. The feature is computed in real-time from multiple microphone signals without requiring knowledge or estimation of the dire…

Cited by 0SourceScholar
2015

Trinicon-BSS system incorporating robust dual beamformers for noise reduction

ICASSP 2015accepted

In this paper, a method of adaptive noise suppression combining spatially robust fixed beamforming and the TRINICON blind source separation algorithm is presented. A multichannel sensor array is first processed using complementary fixed beamformers into maximum and minimum SINR channels. The channel…

Cited by 0SourceScholar