Results 131 to 140 of about 4,760 (175)

Boon and Bane of Curvelet Transform

2010
Candes and Donoho introduced a new system of multiresolution analysis called the curvelet transform. Curvelets take the form of basis elements, which exhibit a very high directional sensitivity and are highly anisotropic. In this paper, we applied the curvelet transform, to generate Tamil OCR, to detect melanoma from microscopic images and to develop a
G. Geetha 0001, V. Ragavi, K. Thamizhchelvy, K. Mariappan, V. Lalitha 0004, S. Shanmuga Priya   +5 more
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Cartoon Approximation with α-Curvelets

2014
It is well-known that curvelets provide optimal approximations for so-called cartoon images which are defi ned as piecewise C2-functions, separated by a C2 singularity curve. In this paper, we consider the more general case of piecewise Cβ-functions, separated by a Cβ singularity curve for β (1;2].
Grohs, Philipp, Keiper, Sandra, Kutyniok, Gitta, Schäfer, Martin   +3 more
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Quaternionic curvelet transform

Optik, 2017
Abstract In this paper, we extend the continuous curvelet transform to the space of quaternion valued functions using convolution. We prove that the quaternionic curvelet transform is consistent with the continuous curvelet transform of complex valued functions.
L. Akila, R. Roopkumar
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Seismic imaging in the curvelet domain and its implications for the curvelet design

SEG Technical Program Expanded Abstracts 2006, 2006
This paper is a first attempt towards the migration of seismic data in the curvelet domain for heterogeneous background velocity models. We first explain how to build a simple curvelet decomposition/reconstruction code, based on the use of Fast Fourier Transforms (FFTs).
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Curvelet Transform for Image Authentication

2006
In this paper, we propose a new image authentication algorithm using curvelet transform. In our algorithm, we apply ridgelet transform to each block which is subbanded from the image after wavelet transform. Experimental results demonstrate this algorithm has good property to localize tampering, and robust to JPEG ...
Jianping Shi, Zhengjun Zhai
openaire   +1 more source

Seismic denoising with nonuniformly sampled curvelets

Computing in Science & Engineering, 2006
The authors present an extension of the fast discrete curvelet transform (FDCT) to nonuniformly sampled data. This extension not only restores curvelet compression rates for nonuniformly sampled data but also removes noise and maps the data to a regular ...
Gilles Hennenfent, Felix J. Herrmann
openaire   +1 more source

Curvelet transform with learning-based tiling

Signal Processing: Image Communication, 2017
Compact signal and image representations are of crucial importance in a variety of application areas. Wavelet and wavelet-like transforms typically divide the frequency plane in a systematic non-adaptive approach. In this paper, we propose a learning-based method for adapting frequency domain tiling using the curvelet transform as the basis algorithm ...
Hasan Al-Marzouqi, Ghassan AlRegib
openaire   +1 more source

Interior tomography with curvelet-based regularization

Journal of X-Ray Science and Technology, 2016
The interior problem, i.e. reconstruction from local truncated projections in computed tomography (CT), is common in practical applications. However, its solution is non-unique in a general unconstrained setting. To solve the interior problem uniquely and stably, in recent years both the prior knowledge- and compressive sensing (CS)-based methods have ...
Liu, Baodong, Katsevich, Alexander, Yu, Hengyong   +2 more
openaire   +3 more sources

Quaternion Ridgelet Transform and Curvelet Transform

Advances in Applied Clifford Algebras, 2018
The relationships between the Fourier, Radon, wavelet, ridgelet, curvelet transforms for real-valued functions have been extensively studied and are well known. The paper under review extends some of these relationships to quaternion-valued functions. A quaternion \(a\) can be represented as \[ a=a_0+a_1 i+a_2 j+a_3 k, \] with \[ ij=k,\; jk=i,\; ki=j,\;
Ma, Guangsheng, Zhao, Jiman
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TEXTURE CLASSIFICATION USING CURVELET TRANSFORM

International Journal of Wavelets, Multiresolution and Information Processing, 2007
Texture classification has long been an important research topic in image processing. Nowadays classification based on wavelet transform is being very popular. Wavelets are very effective in representing objects with isolated point singularities, but failed to represent line singularities.
Arivazhagan Selvaraj, T. G. Subash Kumar, L. Ganesan   +2 more
openaire   +1 more source