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2. Outline. Main result and the relation to Radon TransformRectilinear DFT: General Definition and Properties The Pseudo-Polar FFT (PPFFT)The FFFT and it's relation to structured matricesThe Octa-Polar FFTSummary and on-going work . 3. 2D Fast Fourier Transforms. The computational cost for a si
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1. The Fast Octa-Polar Fourier Transform and its expansion to an accurate discrete radon transform Ofer Levi
2. 2 Outline Main result and the relation to Radon Transform
Rectilinear DFT: General Definition and Properties
The Pseudo-Polar FFT (PPFFT)
The FFFT and its relation to structured matrices
The Octa-Polar FFT
Summary and on-going work
3. 3 2D Fast Fourier Transforms
4. 4 Main Result a new, almost-polar FFTThe Octa-Polar FFT
5. 5 Importance of Polar DFT
6. 6 Relation between Radon and Fourier Transforms
7. 7 Relation between Radon and Fourier Transforms
8. 8 Approximated Polar DFTs
9. 9 Approximated Polar DFTs
10. 10 1D DFT: General Definition and Properties
11. 11 1D DFT: Computability Direct evaluation of the 1D DFT costs o(n2)
12. 12 Example Spectral Decomposition
13. 13 Example Spectral Decomposition
14. 14 Example - Denoising
15. 15 2D DFT Cartesian Grid
16. 16 2D complex exponents
17. 17 2D FFT
18. 18 Applications of rectilinear 2D FFT Spectral Analysis
19. 19 Polar DFT
20. 20 Polar DFT
Direct Polar DFT is impractical
o(n4) and no direct inverse
21. 21 The Pseudo-Polar FFT (PPFFT)(Donoho et. al.)
22. 22 The Pseudo Polar FFT
23. 23 Fractional FFT Algorithm (D. Bailey and P. Swarztrauber 1990)
24. 24 Some basic facts about Toeplitz Matrices
25. 25 FFFT and Structured Matrices
26. 26 The PPFFT Algorithm
27. 27 The PPFFT Matrix notation A can be implicitly applied in O(Nlog(N)) operations
28. 28 Inverse PPFFT
29. 29 Weighted PPFFT
30. 30 The Slow Slant-Stack Transform
31. 31 The Fast Slant-Stack Algorithm
32. 32 The Fast Slant-Stack transform
33. 33
34. 34 Treating The NW/SW and NE/SE grid points sets
35. 35 Summary and Future research