Computation of permeability with Fast Fourier Transform from 3-D digital images of porous microstructures

Digital computation of the fractional Fourier transform

An algorithm for efficient and accurate computation of the fractional Fourier transform is given. For signals with time-bandwidth product N , the presented algorithm computes the fractional transform in O( N log N ) time. A definition for the discrete fractional Fourier transform that emerges from our analysis is also discussed.

Computation of Configuration-Space Obstacles Using the Fast Fourier Transform

Using Fast Fourier Transform in the 3-d Multilevel Fast Multipole Algorithm

In this paper a method is presented how to perform interpolation and anterpolation in both spherical coordinates θ and φ by trigonometric polynomials and the fast Fourier transform (FFT) in the 3-D multilevel fast multipole algorithm (MLFMA). The proposed method is exact in interpolation and anterpolation, and has the high numerical efficiency of FFT. A numerical comparison suggests that the pr...

3-D Image Registration Using Fast Fourier Transform, with Potential Applications to Geoinformatics and Bioinformatics

FFT-based techniques are actively used to register 2-D images, i.e., to find the shift, rotation, and scaling necessary to align one image with the other. It is desirable to extend these techniques to the problem of registering 3-D images. Registration of 3-D images is an important problem in areas such as bioinformatics (e.g., in protein docking) and geoinformatics (e.g., in earth modeling).

Integer fast Fourier transform

In this paper, a concept of integer fast Fourier transform (IntFFT) for approximating the discrete Fourier transform is introduced. Unlike the fixed-point fast Fourier transform (FxpFFT), the new transform has the properties that it is an integer-to-integer mapping, is power adaptable and is reversible. The lifting scheme is used to approximate complex multiplications appearing in the FFT latti...