laboratory of image processing
DESCRIPTION
Laboratory of Image Processing. Pier Luigi Mazzeo [email protected] July 24, 2014. The Fourier Transform with images. Display the obtained fft image. Download from my website the fftshow function , put it in your work directory. The fft examples. The fft examples. - PowerPoint PPT PresentationTRANSCRIPT
![Page 2: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/2.jpg)
The Fourier Transform with images
Display the obtained fft image
Download from my website the fftshow function, put it in your work directory
![Page 3: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/3.jpg)
The fft examples
![Page 4: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/4.jpg)
The fft examples
fftshow(cf, ‘log’)
Try with this circle (its edge appears burred). What does happen?
![Page 5: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/5.jpg)
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).
![Page 6: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/6.jpg)
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).
![Page 7: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/7.jpg)
Gaussian filtering
![Page 8: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/8.jpg)
Gaussian filtering HP(cont.)
![Page 9: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/9.jpg)
Butterworth filtering
![Page 10: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/10.jpg)
Butterworth filtering (cont.)
![Page 11: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/11.jpg)
Butterworth filtering (cont.)
![Page 12: Laboratory of Image Processing](https://reader036.vdocuments.us/reader036/viewer/2022081604/5681326e550346895d9906bd/html5/thumbnails/12.jpg)
Butterworth filtering (cont.)