Prednaska 2 -Fourier transform

time{t} → frequency

• diracuv impuls
• jednotkovy skok

• 1(x+k)-1(x-k) ⇔ 1/pi*u sin (2piku)
  
• vypocet fourier - sinc http://en.wikipedia.org/wiki/Sinc_function
  

<m>af(x)+bf(x) doubleleftright aF(u)+bF(u)</m>

position{x,y} ⇐⇒ frequency & orientation{u,v} <m>Omicron(N^4)</m>

<m>Omicron(N^2log N)</m>

Nyquist frequency: <m>f_max ⇐ 1/2delta</m>