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Wave atom transform is a new multi-resolution technique, which has the ability to adapt to arbitrary local directions of a pattern, and to sparsely represent anisotropic patterns aligned with the axes. In this paper, a de-noising technique is proposed to remove the rician noise from Magnetic Resonance Images using wave atom shrinkage. It is well known that the noise in magnetic resonance imaging has...
This paper presents aircraft target recognition (ATR) system using Inverse Synthetic Aperture Radar (ISAR) images. Knowing the pose of the target can improve the ATR performance (recognition rate and computational complexity). So, we propose in this paper a new pose estimator from ISAR images, based on the axis of symmetry and the similarity measure. The method proposed is compared with several approaches...
This paper presents a new over complete ICAMM to make decomposition the basis for low-bit high-speed image compression on image sub-blocks. Although the over complete independent component analysis basic number is much larger than the original data dimension, most of the coefficients will be zero after performing the basis transform so that this algorithm reaches the low bit-rate compression goal...
One common and traditional method of detecting stored-grain deterioration is by measuring grain temperature. The key to stored-grain temperature measurement by acoustic method is acoustic travel-time measurement. In this paper, a phase transform generalized cross correlation with wavelet transform (WT-PHAT-GCC) method for acoustic travel-time measurement is proposed. An experimental system of acoustic...
Owing to the stochastic nature of discrete processes such as photon counts in imaging, a variety of real-world data are well modeled as Poisson random variables whose means are in turn proportional to an underlying vector-valued signal of interest. Certain wavelet and filterbank transform coefficients corresponding to measurements of this type are distributed as sums and differences of Poisson counts,...
Scintigraphic imagery is an important data source since it provides morphological and functional clinical informations. However, scintigraphic images present very bad quality because of several degradation factors. In fact, the recorded data are embedded in noise modelled as the realisation of Poisson process. The aim of this paper is to provide a framework able to enhance nuclear images quality by...
This paper proposes a robust and accurate multi-pitch estimation method for multiple voices. This method is based on the spectral analysis of the mixture sound multi-scale product. The multi-scale product (PM) consists of making the product of wavelet transform coefficients. The wavelet used is the quadratic spline function. Simulation results showed that the proposed method can robustly estimate...
Image inpainting or completion is a technique to restore a damaged image. Recently various approaches have been proposed. Wavelet transform has been used for various image analysis problems due to its nice multi-resolution properties and decoupling characteristics. We propose to utilize the advantages of wavelet transforms for image inpainting. Unlike other inpainting algorithms, we can expect better...
In this tutorial paper, we are interested in image denoising in the wavelet domain. The objective is to describe in a unifying framework the most relevant methods which exploit Stein's principle to build estimators for images embedded in Gaussian noise. The appealing advantage of Stein's Unbiased Risk Estimate (SURE) is that it does not require a priori knowledge about the statistics of the unknown...
The directional protection of bus-bars using time-frequency transform such as S-transform is presented in the paper. S-transform is used to estimates the phase and amplitude of the fault current signals during fault situations. The difference in phase angle between positive sequence component of the current during fault and pre-fault conditions distinguishes internal faults (bus-bar faults) from external...
Oriented wavelets have attracted attention in recent times due to their superior coding performance of images containing diagonal features. We focus on a scheme which effectively aligns the wavelet transform to edges by lifting between shift-interpolated pixels. While compression is improved, poor specification of the orientation can introduce additional aliasing to the lower resolution subband. In...
This paper proposes a method of image interpolation by estimation and deconvolution of wavelet approximate subband. In this method, wavelet approximate subband that contains much information is firstly interpolated by interpolation methods such as cubic spline in order to find the decimated low-pass component of the image. The low-pass component is then deconvoluted for getting the original image...
To investigate the blind symbol rate estimation of any linear base-band digital modulation scheme with square root raised cosine filter, an algorithm based on cyclic correlation and Haar wavelet transform estimator is proposed. First we use FFT to estimate the bandwidth roughly. Then we set the sampling frequency and range scale of wavelet transform according to bandwidth. Using the signals filtered...
Adaptive playout algorithms are used at the receiver to combat jitter problems in voice over IP (VoIP). The playout algorithms rely on short term estimations of the characteristics of network delay that would be experienced by up-coming voice packets. This paper proposes a new adaptive playout algorithm based on wavelet transform and kernel estimation. The proposed algorithm uses wavelet transform...
Regularization method has been widely used in blind image restoration. Most regularization operators, however, are applied uniformly without considering difference of edge regions, which results in an unsolved trade-off conflict between smooth and edge regions. In this paper, we apply suitable regularization operators to smooth regions and edge regions respectively according to their characteristics...
An Image Quality (IQ) evaluation based wavelet domain denoising and enhancement model for a Vehicle Target Recognition and Assistant Navigation (VTRAN) system is introduced. In order to adapt to a complex atmosphere environment, our model utilizes the IQ parameters as a criterion to search the proper estimation values of the wavelet domain denoising and enhancement model. Firstly, before the wavelet...
This paper presents a technique for speckle reduction in SAR images by using the interscale multiplication in Mallat wavelet transform (MWT) and stationary wavelet transform (SWT). The edge and non-edge regions can be detected from median of squared amplitude in each scale. Applying this technique, the large wavelet coefficients generated by edge region and the small wavelet coefficients or speckle...
Wavelet analysis is a right successor of Fourier analysis based on the self-similarity. It is a very nice tool in industries as same as Fourier one, since wavelet was invented by an engineer. The application has been started at voice and image analyses, especially data compression as MPEG-4, JPEG2000 and so on. We applied wavelet analysis to measurement of time delay of a dynamical system including...
The algorithms to solve the simplest version of spatio-temporal mixture problem in the blind source separation are proposed. The analytic wavelet transform is used to represent time-frequency information and a numerical simulation is given.
This paper presents a new algorithm for estimation of noise (i.e., level of noise) in both gray-scale and color images (GSI, CI). The new technique is called median-absolute deviation (MAD). This technique does require an explicit estimation of the noise level or the signal to noise ratio (SNR), which is usually needed in most of the popular enhancement methods. Performance of the proposed method...
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