This paper presents a efficient non iterative wavelet based image deblocking method which employs a maximum a posteriori (MAP) estimator that uses the Laplace probability density function with local variance to smooth out the blocking artifacts in block discrete cosine transform (DCT) compressed images. We have shown that the noise standard deviation has a strong relationship with the average o...

This paper proposes a speech signal enhancement method in which the wavelet transform scales and thresholds both are adaptive depending on the input noisy signal affected by Additive White Gaussian Noise (AWGN). The proposed Estimated Noise and Adaptive Threshold Bionic Wavelet Transform (ENAT-BWT) method analyses the incoming noisy speech signal at 22 scales, from 7 to 28, of the BWT for negat...

A multiplicative Schwarz overlapping domain decomposition method is considered for solving elliptic boundary value problems. By equipping the relevant Sobolev spaces on the subdomains with wavelet bases, adaptive wavelet methods are used for approximately solving the subdomain problems. The union of the wavelet bases forms a frame for the Sobolev space on the domain as a whole. The resulting me...

A point machine's gap is an important indication of its healthy status. An edge detection algorithm is proposed to measure and calculate a point machine's gap from the gap image captured by CCD plane arrays. This algorithm integrates adaptive wavelet-based image denoising, locally adaptive image binarization, and mathematical morphology technologies. The adaptive wavelet-based image denoising o...

We use asymptotically optimal adaptive numerical methods (here specifically a wavelet scheme) for snapshot computations within the offline phase of the Reduced Basis Method (RBM). The resulting discretizations for each snapshot (i.e., parameter-dependent) do not permit the standard RB ‘truth space’, but allow for error estimation of the RB approximation with respect to the exact solution of the...

In the paper, a robust blind watermarking method is introduced for gray-scale images based on wavelet tree quantization with an adaptive threshold in the extraction. Every block of 2× 2 coefficients of High-Low subbands of the Wavelet tranform are grouped in a block through the parent-child relationship of the wavelet tree. Every scrambled binary watermark bit is embedded into each block based ...

Liandrat and Tchiamichian [2], Bacry et al. [3], Maday and Ravel [4], and Bertoluzza et al. [5] have shown that A dynamically adaptive multilevel wavelet collocation method is developed for the solution of partial differential equations. The the multiresolution structure of wavelet bases is a simple multilevel structure of the algorithm provides a simple way to adapt and effective framework for...

so that the gray-scale graphs can be viewed more clearly. This paper presents a fast adaptive time-frequency analysis method for dealing with the signals consisting of stationary components and transients, which are encountered very often in practice. It is developed based on the short-time Fourier transform but the window bandwidth varies along frequency adaptively. The method therefore behave...

Development of digital content has increased the necessity of copyright protection by means of watermarking. Imperceptibility and robustness are two important features of watermarking algorithms. The goal of watermarking methods is to satisfy the tradeoff between these two contradicting characteristics. Recently watermarking methods in transform domains have displayed favorable results. In this...

To overcome the staircasing effects and simultaneously avoid edge blurring, we present an adaptive partial differential equation combining the total variation with wavelet transform for image restoration. A noise removal algorithm based on variation method and partial difference equations is proposed in this paper. The combining algorithm takes the advantage of both filters since it is able to ...