Carotid Sound Signal Artifact Detection based on Discrete Wavelet Transform Decomposition

Abstract Auscultation methods allow a non-invasive diagnosis of cardiovascular diseases like atherosclerosis based on blood flow sounds of the carotid arteries. Since this process is highly dependent on the clinician’s experience, it is of great interest to develop automated data processing techniques for objective assessment. We have recently proposed a computerassisted auscultation system that we use to acquire carotid blood flow sounds. In this work, we present an approach for detecting artifacts within the blood flow sound caused by swallowing or coughing events. For this purpose, we first decompose the signal using a discrete wavelet transform (DTW). Then, we compute an energy ratio between the DWT scales associated with the signal information with and without artifacts using a sliding window of 1 s length. Evaluation based on Kruskal-Wallis and Wilcoxon rank-sum tests shows a statistically significant difference (p-value<.0001) between the signal with and without artifact. Therefore, the proposed method allows the identification of the studied signal artifacts.

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Noise Suppression in ECG Signals through Efficient One-Step Wavelet Processing Techniques

Journal of Applied Mathematics ◽

10.1155/2013/763903 ◽

2013 ◽

Vol 2013 ◽

pp. 1-13 ◽

Cited By ~ 20

Author(s):

E. Castillo ◽

D. P. Morales ◽

A. García ◽

F. Martínez-Martí ◽

L. Parrilla ◽

...

Keyword(s):

Wavelet Transform ◽

Pregnant Women ◽

Discrete Wavelet Transform ◽

Noise Suppression ◽

Wavelet Denoising ◽

Discrete Wavelet ◽

Ecg Signals ◽

One Step ◽

Exhaustive Study ◽

Processing Techniques

This paper illustrates the application of the discrete wavelet transform (DWT) for wandering and noise suppression in electrocardiographic (ECG) signals. A novel one-step implementation is presented, which allows improving the overall denoising process. In addition an exhaustive study is carried out, defining threshold limits and thresholding rules for optimal wavelet denoising using this presented technique. The system has been tested using synthetic ECG signals, which allow accurately measuring the effect of the proposed processing. Moreover, results from real abdominal ECG signals acquired from pregnant women are presented in order to validate the presented approach.

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Resolution enrichment of side scan sonar image using wavelet based interpolation methods

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.21.12445 ◽

2018 ◽

Vol 7 (2.21) ◽

pp. 375

Author(s):

R Kumudham ◽

S Tarun ◽

R Avinash ◽

V Rajendran

Keyword(s):

Image Processing ◽

Wavelet Transform ◽

Discrete Wavelet Transform ◽

Discrete Wavelet ◽

Stationary Wavelet Transform ◽

Side Scan Sonar ◽

Image Processing Techniques ◽

Sonar Image ◽

Processing Techniques

The resolution of the side scan sonar image which is used to detect on seabed such as mines, ship wrecks, etc is low. This paper helps to utilizes image processing techniques to enhance the resolution and thereby it makes detection and classification of underwater objects accurately. The proposed methods discussed in this paper are Discrete wavelet transform and stationary wavelet transform for enhancing the resolution.

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Comparison of RootMUSIC and Discrete Wavelet Transform Analysis of Doppler Ultrasound Blood Flow Waveforms to Detect Microvascular Abnormalities in Type I Diabetes

IEEE Transactions on Biomedical Engineering ◽

10.1109/tbme.2010.2097263 ◽

2011 ◽

Vol 58 (4) ◽

pp. 861-867 ◽

Cited By ~ 5

Author(s):

Christina Elizabeth Agnew ◽

A J McCann ◽

C J Lockhart ◽

P K Hamilton ◽

G E McVeigh ◽

...

Keyword(s):

Blood Flow ◽

Wavelet Transform ◽

Discrete Wavelet Transform ◽

Doppler Ultrasound ◽

Type I Diabetes ◽

Discrete Wavelet ◽

Type I ◽

Wavelet Transform Analysis ◽

Flow Waveforms

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ENCRYPTION AND DECRYPTION USING IMAGE PROCESSING TECHNIQUES

International Journal of Engineering Applied Sciences and Technology ◽

10.33564/ijeast.2021.v05i12.037 ◽

2021 ◽

Vol 5 (12) ◽

Author(s):

R.Uma Maheshwari

Keyword(s):

Image Processing ◽

Wavelet Transform ◽

Discrete Wavelet Transform ◽

Binary Operation ◽

Speckle Noise ◽

Discrete Wavelet ◽

Arnold Transform ◽

Image Processing Techniques ◽

Encryption And Decryption ◽

Processing Techniques

Images consists various kinds of information which can be used for encryption and decryption of messages through them. This paper proposes a photograph encryption and decryption method to encrypt a covert snapshot with the aid of combining the Arnold transform system within the area and decrypting the duvet photograph through combining inverse Arnold become. First, grow to be a cover snapshot into subparts which consists of eight binary pictures with the aid of decimal value to eight-digit binary operation. Then, change into eight binary snap shots into sub-blocks of eight binary scrambled pixel by means of the Arnold change into, respectively. And then, recombine the sequence of the eight binary scrambled matrices right into a scrambled matrix with 256 grey phases in keeping with the special membership. Discrete Wavelet Transform (DWT) is used to perform picture compression on the input picture and secretly hidden photograph which is finished making use of alpha mixing. Sooner or later, derive an encrypted image from the scrambled photograph with the aid of the Hartley turn out to be. Second, decode the encrypted picture making use of inverse Arnold develop. Inverse DWT is performed to regain the compressed pictures. Simulations indicate that the proposed approach has a bigger photograph scrambling measure, more protection and has the robustness against occlusion and speckle noise attacks.

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