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Signal Processing Commons

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Full-Text Articles in Signal Processing

Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin Jun 2020

Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin

Conference papers

Commercially recorded music since the 1950s has been mixed down from many input sound sources to a two-channel reproduction of these sources. The effect of this approach is to assign sources to locations in a stereo field using a pan-position for each source. The Adress algorithm is a popular way of extracting individual music sound sources from a stereo mixture. A drawback of the Adress algorithm is that when time-frequency components in the stereo mixture are shared between two or more sources, calculating the inter-aural intensity scaling parameter for each source for that time-frequency component is challenging. We show how …


Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin Jun 2020

Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin

Conference papers

Commercially recorded music since the 1950s has been mixed down from many input sound sources to a two- channel reproduction of these sources. The effect of this approach is to assign sources to locations in a stereo field using a pan- position for each source. The Adress algorithm is a popular way of extracting individual music sound sources from a stereo mixture. A drawback of the Adress algorithm is that when time- frequency components in the stereo mixture are shared between two or more sources, calculating the inter-aural intensity scaling parameter for each source for that time-frequency component is challenging. …


On Inpainting The Adress Algorithm, Derry Fitzgerald, Dan Barry Jan 2012

On Inpainting The Adress Algorithm, Derry Fitzgerald, Dan Barry

Conference papers

The Adress algorithm has been demonstrated to be capable of separating sound sources from instantaneous linear mixtures, provided that the sources have a unique pan position in the stereo field. However, a shortcoming of the Adress algorithm is that all time-frequency bins outside of the chosen azimuth range are set to zero, resulting in audible artifacts in the resynthesised sound. Here we show that an inpainting algorithm based on NMF is capable of estimating these missing values and improves on the results obtained using Adress only.


Vocal Separation Using Nearest Neighbours And Median Filtering, Derry Fitzgerald Jan 2012

Vocal Separation Using Nearest Neighbours And Median Filtering, Derry Fitzgerald

Conference papers

Recently, single channel vocal separation algorithms have been proposed which exploit the fact that most popular music can be regarded as a repeating musical background over which a locally non-repeating vocal signal is superimposed. In this paper we describe a novel vocal separator inspired by these approaches which finds the k nearest neighbours to each frame of a spectrogram of the mixture signal. The median value of these frames is then used as the estimate of the background music at the current frame. This is then used to generate a mask on the original complex-valued spectrogram before inversion to the …


User Assisted Separation Using Tensor Factorisations, Derry Fitzgerald Jan 2012

User Assisted Separation Using Tensor Factorisations, Derry Fitzgerald

Conference papers

Recent research has demonstrated that user assisted techniques, where the user provides a ”guide” version of the source to be separated, are capable of giving good sound source separation. Here the user sings or plays along with the target source, and the user input is used to guide the separation towards the source of interest. This is typically done in a factorisation framework, such as non-negative matrix factorisation. Here we extend such approaches to a tensor factorisation framework to deal with multichannel signals. Further, we demonstrate how this framework can be used to improve the output from other user assisted …


On The Use Of Masking Filters In Sound Source Separation, Derry Fitzgerald, Rajesh Jaiswal Jan 2012

On The Use Of Masking Filters In Sound Source Separation, Derry Fitzgerald, Rajesh Jaiswal

Conference papers

Many sound source separation algorithms, such as NMF and related approaches, disregard phase information and operate only on magnitude or power spectrograms. In this context, generalised Wiener filters have been widely used to generate masks which are applied to the original complex-valued spectrogram before inversion to the time domain, as these masks have been shown to give good results. However, these masks may not be optimal from a perceptual point of view. To this end, we propose new families of masks and compare their performance to generalised Wiener filter masks using three different factorisation-based separation algorithms. Further, to-date no analysis …


Harmonic/Percussive Separation Using Median Filtering, Derry Fitzgerald Jan 2010

Harmonic/Percussive Separation Using Median Filtering, Derry Fitzgerald

Conference papers

In this paper, we present a fast, simple and effective method to separate the harmonic and percussive parts of a monaural audio signal.The technique involves the use of median filtering on a spectrogram of the audio signal, with median filtering performed across successive frames to suppress percussive events and enhance harmonic components, while median filtering is also performed across frequency bins to enhance percussive events and supress harmonic components. The two resulting median filtered spectrograms are then used to generate masks which are then applied to the original spectrogram to separate the harmonic and percussive parts of the signal. We …


Using Tensor Factorisation Models To Separate Drums From Polyphonic Music, Derry Fitzgerald, Matt Cranitch, Eugene Coyle Jan 2009

Using Tensor Factorisation Models To Separate Drums From Polyphonic Music, Derry Fitzgerald, Matt Cranitch, Eugene Coyle

Conference papers

This paper describes the use of Non-negative Tensor Factorisation models for the separation of drums from polyphonic audio. Improved separation of the drums is achieved through the incorporation of Gamma Chain priors into the Non-negative Tensor Factorisation framework. In contrast to many previous approaches, the method used in this paper requires little or no pre-training or use of drum templates. The utility of the technique is shown on real-world audio examples.


Drum Transcription In The Presence Of Pitched Instruments Using Prior Subspace Analysis, Derry Fitzgerald, Robert Lawlor, Eugene Coyle Jan 2003

Drum Transcription In The Presence Of Pitched Instruments Using Prior Subspace Analysis, Derry Fitzgerald, Robert Lawlor, Eugene Coyle

Conference papers

This paper demonstrates the use of Prior Subspace Analysis (PSA) as a method for transcribing drums in the presence of pitched instruments. PSA uses prior subspaces that represent the sources to be transcribed to overcome some of the problems associated with other subspace methods such as Independent Subspace Analysis (ISA) or sub-band ISA. The use of prior knowledge results in improved robustness for transcription purposes and enables the method to work more readily in the presence of pitched instruments than other subspace methods. The system presented in this paper attempts to extend the use of PSA to transcribe drum sounds …


Sub-Band Independent Subspace Analysis For Drum Transcription, Derry Fitzgerald, Robert Lawlor, Eugene Coyle Jan 2002

Sub-Band Independent Subspace Analysis For Drum Transcription, Derry Fitzgerald, Robert Lawlor, Eugene Coyle

Conference papers

While Independent Subspace Analysis provides a means of separating sound sources from a single channel signal, making it an effective tool for drum transcription, it does have a number of problems. Not least of these is that the amount of information required to allow separation of sound sources varies from signal to signal. To overcome this indeterminacy and improve the robustness of transcription an extension of Independent Subspace Analysis to include sub-band processing is proposed. The use of this approach is demonstrated by its application in a simple drum transcription algorithm.