Transcript
Page 1: Laboratory of Image  Processing

Laboratory ofImage Processing

Pier Luigi [email protected]

July 24, 2014

Page 2: Laboratory of Image  Processing

The Fourier Transform with images

Display the obtained fft image

Download from my website the fftshow function, put it in your work directory

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The fft examples

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The fft examples

fftshow(cf, ‘log’)

Try with this circle (its edge appears burred). What does happen?

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Filtering in the frequency domain (LP)

• Try to use different cut off (i.e. 5 and 30).• Try to use a circle with a gentle cutoff (i.e. b).

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Filtering in the frequency domain (HP)

• Try to use different cut off (i.e. 5 and 30).• Try to use a circle with a gentle cutoff (i.e. b).

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Gaussian filtering

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Gaussian filtering HP(cont.)

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Butterworth filtering

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Butterworth filtering (cont.)

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Butterworth filtering (cont.)

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Butterworth filtering (cont.)


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