Frequency domain Flashcards
(7 cards)
1
Q
Discrete 2D Fourier transform (DFT).
A
2
Q
Sampling theorem in 2D.
A
πΉπ = 1/π₯π > 2π’πππ₯ and πΉπ = 1/π₯π > 2π£πππ₯
Where π’πππ₯ and π£πππ₯ are the maximum spatial frequencies of the signal along X and Y, respectively
3
Q
What is aliasing.
A
- Undersampling
- Can be compensated by means of a LPF
4
Q
Spectrum and phase of the DFT.
A
β¦
5
Q
How to apply a filter in the frequency domain.
A
DFT -> G=FH -> IDFT
6
Q
Low pass filters + functions.
A
Used for smoothing.
Types:
- Ideal
- Butterworth
- Gaussian
7
Q
High pass filters + functions.
A
Used for sharpening.
Types:
- 1 - H(Ideal)
- 1 - H(Butterworth)
- 1 - H(Gaussian)
