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Could someone explain the general idea behind using FFT in these situations (excusing my ignorance)? I recall it from my university days but that was completely
by aidos 14y ago
Could someone explain the general idea behind using FFT in these situations (excusing my ignorance)? I recall it from my university days but that was completely out of context. I know you can use it to decompose audio signals into frequency components, I don't understand how it applies to images though.
- kens 14y agoThe basic idea is that just as an audio signal can be decomposed into frequency components, an image can be decomposed into frequency components, but in two dimensions. (Imagine stripes of varying frequency and direction instead of sine waves of various frequencies.) Sharp edges in an image have high frequency components, just like a sharp transition in an audio signal. Filtering the high frequencies will blur the image, while filtering low frequencies will enhance edges. This is very oversimplified, but will hopefully give you a bit of an idea. I encourage people to learn more about Fourier theory, because it explains a lot. One introductory page that you may find useful is: http://cns-alumni.bu.edu/~slehar/fourier/fourier.html http://cns-alumni.bu.edu/~slehar/fourier/fourier.html
- aidos 14y agoThat makes perfect sense. Thanks for the link - that's given me a much better intuitive understanding. I'll have a dig around some of the other transformations mentioned now.
- deleted 14y ago[deleted]