Image Processing Reference

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Multiplier value to 0.1, 1 (default), and 10. Observe and compare the

effects of varying the multiplier on each reconstruction method. Does

it affect each method the same? Why or why not? What seems to be the

optimal value for this multiplier for each case?

pdFt exercises

1. Use
pdFt
in MATLAB to generate PDFT, Born and Cepstrum recon-

structions for a square target (Choice 2) using a permittivity of 1.2

and a minimum of 12 sources and 120 receivers. For the prior use a

square shape with the default widths. (Set maximum image scale to

0.5 m for better results.) How does the reconstructed image using the

PDFT method compare with the Born reconstruction? Which method

performs the best? Why do you think this is?

2. Repeat the process described in the previous example applying the

PDFT method described, and then once again without using the PDFT

method. This time compare the performance of the Cepstrum method

outputs for each case. How do these reconstructed images compare?

Discuss your observations for each Cepstrum reconstruction paying

special attention to the scales. Which method performs the best? Why

do you think this is?

3. Repeat the process described in the previous example applying the

PDFT method described, with the exception of setting the prior widths

equal to 0.06. Please discuss your observations for the PDFT and the

Cepstrum reconstructions. How does this affect the results? Why do

you think this is?

4. Repeat the process described in the previous example applying the

PDFT method described, with the exception of setting the prior offsets

equal to 0.1. Discuss your observations for the PDFT and the Cepstrum

reconstructions. How does this affect the results? Why do you think

this is?

5. Use
pdFt
in MATLAB to generate PDFT, Born, and Cepstrum recon-

structions for the square and circle target (Choice 4) using a permit-

tivity of 1.2 and a minimum of 12 sources and 120 receivers. For the

prior, use a two shape combination of a circle and a square that are

centered on the appropriate corresponding target location. The prior

shape sizes should be slightly bigger than the target dimensions. Save

images of the reconstructed images and the prior shapes for review.

Did the use of the prior improve the reconstructed images?

6. Use
pdFt
in MATLAB to generate PDFT, Born, and Cepstrum recon-

structions for any target consisting of two objects (Choice 1, 3, or 5)

using any valid permittivity and a minimum of 6 sources and 120

receivers. Run the reconstructions twice, using PDFTs as input to

the Cepstrum method and again using only the Born as inputs to the

Cepstrum method. Be sure to show the individual Born and Cepstrum

reconstructions for each source. Discuss your observations for the

individual Born and Cepstrum reconstructions for each source for

both methods. What are some of the differences between using the two

inputs? Which method performs the best? Why do you think this is?

7. Use
pdFt
in MATLAB to generate PDFT, Born, and Cepstrum recon-

structions for the target set consisting of a triangle, a square, and a circle

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