Results 121 to 130 of about 1,028 (168)

Curvelet transform on the sphere

IEEE International Conference on Image Processing 2005, 2005
Spherical maps occur in a range of applications for instance in geophysics or in astrophysics with the study of the cosmic microwave background (CMB) radiation field, where observations are over the whole sky. Analyzing these images requires specific tools.
Pierrick Abrial, Jean-Luc Starck, Yassir Moudden, Maï K. Nguyen   +3 more
openaire   +2 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
openaire   +1 more source

Curvelet transform with adaptive tiling

SPIE Proceedings, 2012
The curvelet transform is a recently introduced non-adaptive multi-scale transform that have gained popularity in the image processing field. In this paper, we study the effect of customized tiling of frequency content in the curvelet transform. Specifically, we investigate the effect of the size of the coarsest level and its relationship to denoising ...
Hasan Al-Marzouqi, Ghassan AlRegib
openaire   +1 more source

Uniform Discrete Curvelet Transform

IEEE Transactions on Signal Processing, 2010
An implementation of the discrete curvelet transform is proposed in this work. The transform is based on and has the same order of complexity as the Fast Fourier Transform (FFT). The discrete curvelet functions are defined by a parameterized family of smooth windowed functions that satisfies two conditions: i) 2π periodic; ii) their squares form a ...
Truong T. Nguyen, Hervé Chauris
openaire   +1 more source

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
openaire   +1 more source

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
openaire   +1 more source

The monogenic curvelet transform

2010 IEEE International Conference on Image Processing, 2010
In this article, we reconsider the continuous curvelet transform from a signal processing point of view. We show that the analyzing elements of the curvelet transform, the curvelets, can be understood as analytic signals in the sense of the partial Hilbert transform.
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

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

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