fft

[Solved] Transformation with High Pass Filter [closed]

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n1=rgb2gray(imread(‘fin.jpg’)); imshow(n1); F=fft2(double(n1)); %Calculate Size of Image [M,N]=size(F); %Distance Radius Size D0=50; n=2; u=0:(M-1); v=0:(N-1); idx=find(u>M/2); u(idx)=u(idx)-M; idy=find(v>N/2); v(idy)=v(idy)-N; [V,U]=meshgrid(v,u); %Distance Calculation for High Pass Filter using Distance Formula D=sqrt(U.^2+V.^2); H=double(D>D0); subplot(2,1,1); imshow(fftshift(H)); G=H.*F; g=real(ifft2(double(G))); [a,b]=size(g); for x=1:a for y=1:b sharpen_image(x,y)=(g(x,y))*(-1)^((x)+(y)); end end figure imshow(sharpen_image); OUTPUT solved Transformation with High Pass Filter [closed]

[Solved] How to combine low and high frequencies of two images in Matlab [closed]

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You’ve basically outlined the right approach which I’ll summarize here: 1) Do the 2D FFTs. 2) Multiply them by a weighting factor. If you’re FFTs are in (Real, Imaginary) form, multiply both components by the weight, and if (Magnitude, phase) just multiple the magnitude. If you’re interested in just high and low frequencies, this will … Read more

[Solved] Is my program ready for FFT?

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What does the data in my List is representing in its current form? In its current form, you are getting the raw byte sequence from the file, except from the header which you are removing explicitly. The mapping between raw bytes and the corresponding data sample value is in general non-trivial, and varies according to … Read more