CH2 Image sampling and acquisition Flashcards
1
Q
Condition for a perfect recovery (Nyquist criterion)
A
w_max < pi / T
2
Q
A function f(x) that is bandlimited to w_max can be reconstructed exactly from its equidistant samples provided that the sampling step …
A
T < pi / w_max
3
Q
Ideal sampling is modeled as a multiplication with
A
a sequence of Dirac impulses (ideal samplign function)
4
Q
Sampling … the Fourier transform of the image
A
periodize
5
Q
Perfect recovery is possible only if the image is sampled at or above the Nyquist pulsation …
A
w_max / 2
6
Q
Undersampling produce …
A
Aliasing.
It can be prevented by ideal lowpass prefilter prior to sampling
