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1

Usefulness of the matching pursuit method in phonocardiographic signal analysis

Damps Natalia, Kłaczyński Maciej

Vibrations in Physical Systems

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2021

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Vol. 32, nr 1

art. no. 2021102

EN

This paper presents a phonocardiographic signal analysis with special emphasis on the Matching Pursuit method. To the knowledge of the authors, this method has not been used before to analyze PCG (phonocardiogram) signals. For this reason, its usefulness for this signal type was tested and a dictionary of Gabor atoms was created. Based on these findings, PCG signal analysis was performed as a Wigner-Ville distribution and compared with a spectrogram. Observing the obtained graphs, it was found that the Wigner-Ville map gives more detailed information about the frequencies which make up the given signal and the time of their occurrence. This method can be used to detect anomalies and pathologies of the heart.

2

Enhancing the resolution of time–frequency spectrum using directional multichannel matching pursuit

Xu Lu, Yin Xingyao, Li Kun

Acta Geophysica

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2020

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Vol. 68, no. 6

1643--1652

EN

Matching pursuit is able to decompose signals adaptively into a series of wavelets and has been widely applied in signal processing of the geophysical felds. Single-channel matching pursuit could not take into account the lateral continuity of seismic traces, and the recent multichannel matching pursuit exploits the lateral coherence as a constraint, which helps to improve the stability of decomposition results. However, atoms searched by multichannel matching pursuit currently are just shared by lateral seismic traces at the same time slicers. The lack of directionality in multichannel search strategies leads to irrationality in dealing with large dip angle seismic traces. Considering that the waveforms of refection events are relatively continuous and similar, an improved multichannel matching pursuit is proposed to realize the directional decomposition of adjacent signals. Based on the principle of seismic refection events tracking and identifcation, directional multichan nel decomposition of seismic traces is realized. The seismic channel to be decomposed is correlated with the time shift of the optimal atom determined by the previous seismic channel. The time position of the maximum correlation indicates the center time of the optimal atom. Optimal atoms identifed by one iteration of multichannel decomposition have the same frequency and phase parameters, diferent center time and amplitude parameters. The center time of the optimal atoms is consistent with seismic refection events. Tests illustrate that the algorithm can successfully reconstruct 2D seismic data without reducing accuracy. Besides, the application of feld data is of great signifcance for reservoir exploration and hydro-carbon interpretation.

3

Normalization effects in matching pursuit algorithm with gabor dictionaries

Różański P. T.

Journal of Applied Computer Science

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2018

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Vol. 26, nr 2

187--199

EN

The matching pursuit (MP) algorithm is a greedy method for signal decomposition used in video coding, data compression, and, particularly, analysis of EEG signals in various paradigms, including P300 and ER(D)S (motor imagery). An important issue for MP implementation is a correct treatment of normalization of atoms (functions) used in computations. Failing to account for normalization-related effects may affect both the numerical stability and the reliability of the algorithm. This paper describes these normalization effects, evaluates their impact on the algorithm’s performance, and describe the proper approach together with a ready-to-use implementation, available under a General Public Licence (GPL). Several performance optimizations used as a part of this implementation are also described.

4

Matching Pursuit Algorithm in Assessing the State of Rolling Bearings

Jonak K., Krukow P.

Applied Computer Science

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2017

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Vol. 13, no 2

61--71

EN

In this paper the results of Matching Pursuit (MP) Octave algorithm applied to noise, vibration and harness (NVH) diagnosis of rolling bearings are presented. For this purpose two bearings in different condition state were examined. The object of the analysis was to calculate and present which energy error values of MP algorithm give the most accuracy results for different changes in bearing structures and also how energy values spread in time-frequency domain for chosen energy error value.

5

Dictionary Based Intra Prediction for Image Compression

Sahoo Arabinda, Das Pranati

Annals of Computer Science and Information Systems

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2017

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Vol. 10

73--76

EN

Recently image coding has been importantand in many field it is necessary. Recently varioussparse algorithms have been developed for imagecompression. This paper presents a dictionary basedblock intra prediction for image compression withconstruction of an adaptive trained dictionary. Theadaptive trained dictionary is prepared using K-SVDalgorithm. K-SVD algorithm update the dictionarybased on the sparse algorithms and given image. Theprediction residuals selected from different image areused for dictionary training. The orthogonal matchingpursuit (OMP) algorithm have employed for selectionof dictionary elements and encoding. The proposedmethod is then integrated into 9 mode H.264 intracoding. Performance of proposed method comparedwith existing methods. Simulation result shows thatproposed scheme has improved efficiency as comparedto existing schemes.

6

Zastosowanie adaptacyjnej dekompozycji sygnału do identyfikacji źródeł wolnozmiennego pola magnetycznego

Pałczyńska B.

Przegląd Elektrotechniczny

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2015

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R. 91, nr 8

42--45

PL

Przedstawiono metodę analizy i klasyfikacji sygnałów zmiennych w czasie na podstawie adaptacyjnej dekompozycji sygnału opartej na metodzie „pogoni za dopasowaniem” (ang. Matching Pursuit). Rozważono czynniki określające dokładność adaptacyjnego rozwinięcia sygnału pomiarowego, reprezentującego przebieg czasowy indukcji pola magnetycznego. Zaproponowano sposób identyfikacji źródeł małoczęstotliwościowego pola magnetycznego na podstawie analizy struktur czasowo-częstotliwościowych, występujących w spektrogramie.

EN

The method of analysis and classification of time-vary signals based on the adaptive signal decomposition, using the matching pursuit algorithm was presented. Determinants of the accuracy of the adaptive approximation of measuring signal, representing the magnetic field induction waveform were considered. The way of identification of the sources of the low-frequency magnetic field on the basis of an analysis of time-frequency structures, occurring in the adaptive spectrogram was proposed.

7

Network anomaly detection based on signal processing techniques

Andrysiak T., Saganowski Ł., Maszewski M.

Image Processing & Communications

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2013

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Vol. 18, no. 1

15--21

EN

The article depicts possibility of using Matching Pursuit decomposition in order to recognize unspecified hazards in network traffic. Furthermore, the work aims to present feasible enhancements to the anomaly detection method, as well as their efficiency on the basis of a wide collection of pattern test traces.

8

Anomaly Detection Framework Based on Matching Pursuit for Network Security Enhancement

Renk R., Hołubowicz W.

Journal of Telecommunications and Information Technology

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2011

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nr 1

32-36

EN

In this paper, a framework for recognizing network traffic in order to detect anomalies is proposed. We propose to combine and correlate parameters from different layers in order to detect 0-day attacks and reduce false positives. Moreover, we propose to combine statistical and signal-based features. The major contribution of this paper are: novel framework for network security based on the correlation approach as well as new signal based algorithm for intrusion detection using matching pursuit.

9

Zastosowanie opóźnień milisekundowych do minimalizacji oddziaływania robót strzałowych na obiekty budowlane

Pyra J.

Górnictwo i Geoinżynieria

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2010

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R. 34, z. 2

527-536

PL

W artykule omówiono systemy zadawania opóźnień milisekundowych podczas detonacji ładunków materiału wybuchowego umieszczonego w caliźnie skalnej. Przedstawiono również przykłady analizy drgań wzbudzanych detonacją MW. Na tle dotychczasowych analiz i ich wyników zaprezentowano metodę pogoni za dopasowaniem uzupełnioną spektrum odpowiedzi. Podane przykłady potwierdzają zasadność zastosowania tej metody oraz informacji uzyskanych w wyniku takiego sposobu analizy rejestrowanych drgań.

EN

The systems of milisecond delays during detonation of explosive (or charge) placed in the rock mass are presented in this paper there. The examples analysis of vibrations induced with explosions MW are also shown. On the background of analysis and their results there was presented a method so-called Matching Pursuit completed spectrum response. The examples confirm the validity of this method and information obtained as a result of this analysis registered vibrations.

10

An attempt of the application of matching pursuit mp with Gabor dictionary for evaluation of ride comfort disturbance level

Grzegożek W., Szczygieł J.

Journal of KONES

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2009

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Vol. 16, No. 2

149-158

EN

Ride comfort has always been considered to be essentialfor vehicle development. Nowadays it is one of aspects of wehicle industry that is getting more and more important. Disturbances in vehicle motion, for example drive across an obstacle or drive of a rail vehicle across the transition curve may be the reason for ride comfort disturbances. These excitation values may define the subjective negative comfort assessment by a passenger or a driver. Sudden changes of acceleration with low frequencies are particularly perceptible. That is why the attempts of evaluation of these disturbances are included in standards as PCT and PDE indexes for rail vehicles. In order to designate these indexes filtration of the recorded lateral acceleration runs is done. The values of changes of lateral acceleration, of lateral jerk and roll rate in time intervals are defined. This kind of analysis in which only the amplitudes of values measured were taken into account and in which 2 Hz filter was used may cause discrepancy between subjective assessment and evaluated level of vibration. Wavelet transform that is the tool of time-frequency analysis makes non-stationary signals such as acceleration signals in case of comfort disturbances possible. The problem of evaluation of vibration level that is basedon wavelet transform analysis appears. In order to evaluate this vibration level algorithm of matching pursuit MP may be used to match the mother wavelet to the recorded signal in the best way possible. The article presents an attempt of matching pursuit algorithm with Gabor dictionary for evaluation of the discomfort level that was based on the run recorded in the tram.

11

On tuning redundant dictionary parameters in signal-based anomaly detection system

Saganowski Ł., Choraś M., Renk R., Hołubowicz W.

Image Processing & Communications

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2009

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Vol. 14, no 4

29-34

EN

In our previous work innovative recognition algorithm applied to Anomaly Detection System has been presented. We proposed to use Matching Pursuit Mean Projection (MP-MP) of the reconstructed network signal to recognize anomalies in network traffic. In this paper we focus on evaluation of parameters of the redundant dictionary used in our methodology. In the experimental section we present the results of tuning the parameters of the redundant dictionary used in our system.

12

Correction of satellite images deformations using tropospheric aerosols

Khireddine A., Salvestrini J. P.

Image Processing & Communications

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2008

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Vol. 13, no 3-4

31-39

EN

Modern digital technology has made it possible to manipulate multi-dimensional signals with systems that range from simple digital circuits to advanced parallel computers [1, 2]. The theory of Wiener gives the filter which minimizes the residual error (difference between the real exit and the desired exit), thus, the 2D Wiener filter gives a solution to many problems of two-dimensional signal processing such as the restoration of degraded images. However, since the determination of this filter implies the solution of a linear equations system with great dimension, fast algorithms are necessary. The effort of calculation for the determination of the coefficients of this filter depends primarily on the statistical nature of the input signal. The images provided by sensors are intended for various applications, however the geometrical deformations which accompanies them make them not easily exploitable. The goal of the geometrical correction is to generate an image presented according to one of the forms of projections cartographic of everyday usage; an image whose geometry is superposable to another is already corrected image. The method proposed in this paper is the analytical approach. And the optimal filter is the bicubic filter. Our survey concern in working out a sequential algorithm of numeric synthesis filter. To realize an Infinite Impulse Response (IIR) according to a model we need to apply the new concept of the parallelism; so to conceive an intended parallel algorithm to be executed on a map multiprocessors.

13

Matching pursuit algorithm with frame-based auditory optimized WP-dictionary for audio transient modeling

Petrovsky A., Petrovsky A.

Elektronika : konstrukcje, technologie, zastosowania

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2008

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Vol. 49, nr 4

74-79

EN

This paper presents the method of matching pursuit (MP) with frame based psychoacoustic optimized wavelet packet (WP) dictionary for selecting most relevant components to be used in compact representation transient part of signal. The wavelet dictionary for matching pursuit is composed of functions that are bounded by frame based psychoacoustic adaptive wavelet packet. Psychoacoustic motivated entropy based cost functions allow us to minimize perceptual relevance and adapt wavelet packet structure with reducing dictionary size. The proposed methodology for selecting most relevant components is based on maximizing the matching between the auditory excitation scalograms associated with original and modeled signal correspondingly. This technique allows to significant reduce the number of MP atoms in compare with well known techniques based on damped sinusoids and over-complete WP -dictionary.

PL

Artykuł prezentuje algorytm poszukiwania dopasowującego (ang. Matching Persuit) z percepcyjnie zoptymalizowanym słownikiem opartym na pakietowej transformacji falkowej. Algorytm zastosowano do jak najbardziej trafnego wyboru komponentów użytych do zwartego przedstawienia przejść w sygnale audio. Poszukiwanie dopasowujące wykorzystuje słownik złożony z funkcji określonych pakietową transformacją falkową, która percepcyjnie adaptuje się do ramek sygnału. Oparta na entropii i ocenie psychoakustycznej funkcja kosztu pozwala zminimalizować zależności percepcyjne i przystosować pakietową transformację falkową do ograniczonego rozmiaru słownika. Zaproponowana metodologia wyboru najbardziej istotnych komponentów opiera się na maksymalizacji dopasowania pomiędzy skalogramami percepcyjnego wzbudzenia skojarzonymi odpowiednio z sygnałem oryginalnym i modelowanym. Technika ta pozwala istotnie zredukować liczbę funkcji atomowych poszukiwania dopasowującego w stosunku do znanych technik, które wykorzystują tłumione sinusoidy i nadkompletne słowniki pakietowej transformacji falkowej.

14

Topographic Matching Pursuit of spatio-temporal bioelectromagnetic data

Gratkowski M., Haueisen J., Arendt-Nielsen L., Zanow F.

Przegląd Elektrotechniczny

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2007

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R. 83, nr 11

138-141

EN

A method for multichannel biomedical signal analysis was developed and is presented in this paper. The method is based on the Matching Pursuit algorithm. It creates approximations of spatiotemporal distributions of multichannel data using a relatively small number of components chosen from a very big and redundant set. The components are distributed both in time and space and their amplitude and phase parameters are independent for all channels. The method was validated on both artificial and bioelectromagnetic data (EEG, MEG).

PL

Artykuł prezentuje metodę analizy wielokanałowych sygnałów biomedycznych bazującą na algorytmie Dopasowania Kroczącego. Tworzy ona approksymacje rozkładów wielokanałowych sygnałów za pomocą relatywnie małej liczby komponentów wybranych z bardzo dużego i redundantnego zbioru. Metoda została przetestowana zarówno na danych symulowanych, jak i bioelektromagnetycznych, EEG, MEG.

15

High compression rate image coder based on dictionary of base functions

Saganowski Ł.

Image Processing & Communications

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2007

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Vol. 12, no 2

27-33

EN

This paper presents high compression rate image coder based on Dictionary of Base Functions. Dictionary of Base Functions - BFB is a main part of proposed image compression. Proposed BFD has a ability to capture the characteristic of input images especially in high compression rates. Proposed image coder will be compared to the existing still image compression standard.

16

Analiza akustycznych obrazów falowych w oparciu o parametryzację sygnału za pomocą metody "pogoń za dopasowaniem" (Matching Pursuit)

Wawrzyniak K.

Prace Instytutu Nafty i Gazu

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2006

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nr 137

427-436

PL

Technika "pogoń za dopasowaniem" (ang. Matching Pusuit, MP) jest metodą analizy sygnałów o wysokiej rozdzielczości w przestrzeni czas - częstotliwość. Metoda ta opiera się na adaptacyjnych przybliżeniach sygnału za pomocą niewielu funkcji zwanych atomami, wybieranych z dużego i redundantnego słownika (zbioru atomów). Atomy Gabora (funkcja Gaussa modulowana sinusem) zapewniają optymalną lokalizację w przestrzeni czas - częstotliwość elementów składowych sygnału. Prezentowana praca omawia zastosowanie algorytmu MP do analizy akustycznych obrazów falowych. Przedstawia metodykę usuwania fali propagującej w płuczce oraz dekompozycję pola falowego w celu wydzielenia z akustycznych obrazów falowych fal użytecznych: P, S i Stoneleya. Spośród atomów Gabora najlepiej dopasowanych do przetwarzanego obrazu falowego wybierane są te, które reprezentują fale użyteczne. Na podstawie parametrów wyselekcjonowanych atomów Gabora, (położenia, częstotliwości i szerokości w domenie czasu), określane są własności czasowo-częstotliwościowe fal akustycznych.

EN

Matching Pursuit (MP) algorithm is high-resolution signal analysis in time-frequency space. The method relies on an adaptive approximation of a signal by means of Gabor atoms chosen from a very large and redundant dictionary of function. This paper presents application of MP algorithm to analyses of Acoustic Full Waveforms. Methodology of extraction of fluid wave and decomposition of AFW into separate P, S and Stoneley waves is shown. Gabor atoms that fit best to the signal structure were analyzed in order to select the ones that represent the acoustic waves. On the basis of the parameters of these atoms (position, width in time and frequency) time-frequency properties of waves are presented.

17

Scalable image coder using base functions dictionary

Saganowski Ł.

Image Processing & Communications

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2006

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Vol. 11, no 1

107-113

EN

This paper presents scalable image coder based on Matching Pursuit image decomposition and wavelet transformation. Matching Pursuit algorithm uses dictionaries to decompose image on elementary base functions (atoms). Bi-orthogonal Daubechies wavelet 9/7 filterbank is used to obtain coarse and filtered subimage which can be considered as base layer of coded image.

18

Multiplicative waveforms decomposition

Serir A.

Machine Graphics and Vision

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2000

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Vol. 9, No. 1/2

389-396

EN

This paper introduces a nonel nonlinear low-level representation of an image with signal-dependent noise. For multiplicative noisy image, we introduce an algorithm called multiplicative matching pursuit decomposition MMPD, that decomposes the signal containing the intrinsic variation into a nonlinear expansion of waveforms that are selected from redundant dictionary of functions to best match the signal local structures. The convergence of this new multiplicative decoposition has been proved and tested in practice. An application to speckle reduction in SAR images is described.