what is the meaning of bandwidth in octav?

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hind 2011-11-23

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Jan 2011-11-24

@hind: No, your question is not trivial. It contains not enough details to be answered easily - or at all.

hind 2011-11-24

actually I want to write code of circular gabor filter in matlab and there is relations between (gaussian sigma σ) and (central frequency of gabor fc) is described as

σ.fc= (1/pi).sqrt(ln2/2).((2^ΔF+1)/(2^ΔF-1))

where ΔF (∈[0.5, 2.5]) denotes the bandwidth in octave. and σ with five-pixel width

Idon't know how to represent this correctly

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hind 2011-11-24

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https://ww2.mathworks.cn/matlabcentral/answers/22101-what-is-the-meaning-of-bandwidth-in-octav#answer_29147

在 MATLAB Online 中打开

this my code is it rghit?

sigma = 5;
fc= (1/pi*sigma)*sqrt(log(2)/2)*(((2^1.12)+1)/((2^1.12)-1));
for x = -fix(sigma):fix(sigma)
for y = -fix(sigma):fix(sigma)
          G(fix(sigma)+x+1,fix(sigma)+y+1) = (exp(-.5*((x/sigma)^2+(y/sigma)^2)))* cos(2*pi*fc*(sqrt((x)^2+(y)^2)));
      end
  end