One of the advantages of the Discrete Wavelet Transform (DWT) compared to Fourier Transform (e.g. Discrete Cosine Transform DCT) is its ability to provide both spatial and frequency localization of image energy. However, WT coefficients, like DCT coefficients, are defined by magnitude as well as sign. While algorithms exist for the coding of wavelet coefficients magnitude, there are no efficien...

BACKGROUND Since the electrocardiogram (ECG) signal has a low frequency and a weak amplitude, it is sensitive to miscellaneous mixed noises, which may reduce the diagnostic accuracy and hinder the physician's correct decision on patients. METHODS The dual tree wavelet transform (DT-WT) is one of the most recent enhanced versions of discrete wavelet transform. However, threshold tuning on this...

Maximum nongaussianity principle for ultrasonic flaw detection Hua-ming LEI, Wei LIANG, Pei-wen QUE Department of Instrument Science and Engineering, Shanghai Jiaotong University, Shanghai, 200240, P.R.China E-mail: [email protected] Abstract: The noise suppression techniques with wavelet transform (WT) are widely used in non-destructive testing and evaluation (NDT&E). In this paper, we have an...

This paper presents the combination of advanced signal processing techniques and the machine intelligence approach to classify the power quality events. The Wavelet Transform (WT) and the S – Transform (ST) are utilized to extract the important useful features of the disturbance signal. The features extracted by using the above approaches are used to train a PNN classifier for automatic classif...

Introduction: One of the major problems in the development of nuclear medicine images is the presence of noise. The noise level in nuclear medicine images is usually reduced by the analysis of imaging data in a Fourier transform environment. The main drawback of this environment belongs to low signal to noise ratio in high frequencies because removing noise frequencies may remove data and times...

Transform (WT) has been proved to be a very useful tool for image processing in the recent years. However, WT is very computationally rigorous process requiring novel and computationally competent method to achieve image compression. The concurrent transformation of the image might be one of the solutions to this problem. In this paper, we investigate and analyze the concurrency in communicatin...

One of the advantages of the Discrete Wavelet Transform (DWT) compared to Fourier Transform (e.g. Discrete Cosine Transform DCT) is its ability to provide both spatial and frequency localization of image energy. However, WT coefficients, like DCT coefficients, are defined by magnitude as well as sign. While algorithms exist for the coding of wavelet coefficients magnitude, there are no efficien...

Introduction: A major problem facing the patients with chronic liver diseases is the diagnostic procedure.  The conventional diagnostic method depends mainly on needle biopsy which is an invasive method. There  are  some  approaches  to  develop  a  reliable  noninvasive  method  of  evaluating  histological  changes  in  sonograms. The main characteristic used to distinguish between the normal...

Dielectric insulation is mostly affected due to Partial discharge (PD) pulses, which are resultants of various stress parameters. Normal acquired signal from any insulating material has two components namely actual partial discharge (PD) pulses and noise. Noise suppression is crucial before any (PD) data analysis. PD pulses are short transient, randomly occurred and non-stationary signals. Rece...

We present a new method for adaptive surface meshing and triangulation which controls the local level–of–detail of the surface approximation by local spectral estimates. These estimates are determined by a wavelet representation of the surface data. The basic idea is to decompose the initial data set by means of an orthogonal or semi–orthogonal tensor product wavelet transform (WT) and to analy...