image quality 1

# image quality 1 - 3.0 Basic Imaging PrinciplesImage Quality...

This preview shows pages 1–6. Sign up to view the full content.

3.0 Basic Imaging Principles—Image Quality The primary purpose of a medical imaging system is to create images of the internal structures and function of the body to be used for diagnostic or therapeutic monitoring purposes. The degree to which this is possible depends strongly on the quality of the images •Contrast •Resolution •Noise •Artifacts •Distortion •Accuracy—quantitative and/or diagnostic

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Summary of Previous Lecture Fourier Transform F(u)=FT(f(x)), linearity, scaling, convolution, shifting, conjugate symmetry For spatial transforms, frequency is 1/cm, u=0 is the DC or average, conventions for display (+- frequency with zero in center vs 0 at left, sampling frequency on right, Nyquist in center for the FFT) For LSI systems, output in terms of PSF (h) or Transfer Function (H) 2D FT for circularly symmetric objects results in consideration of 1D Hankel transform, analog of the sinc function is the jinc function Sampling leads to consideration of FT of a sampling (comb) function Sampling is product of sampling function with function to be sampled. Hence the FT is convolved with a periodic function leading to replicates in the spectrum spaced at f s =1/ x If f s > 2u c where u c is the highest frequency in the spectrum then sampling is adequate. Otherwise alias frequencies contaminate the spectrum from the replicates.
Alternate answer?: “You can’t handle the truth!” Col. Jessep: A Few Good Men

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
MR PD-W

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 10/30/2010 for the course MP 230 taught by Professor Macfall during the Fall '10 term at Duke.

### Page1 / 30

image quality 1 - 3.0 Basic Imaging PrinciplesImage Quality...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online