about fourier transform
信息
此问题已关闭。 请重新打开它进行编辑或回答。
显示 更早的评论
what is the best reconstruction in term of quality of the image when using fft2 and ifft2 without pre and post processing.
2 个评论
Sean de Wolski
2011-3-22
What do you mean "What is the best reconstruction?" Explain your question and you'll get better answers.
si kijang
2011-3-28
回答（2 个）
Walter Roberson
2011-3-22
0 个投票
Are you asking: "If I have an image and I fft2() the image, and I ifft2() the result of that, then what is the maximum difference I should expect for any one pixel compared between the original and reconstructed image" ?
1 个评论
si kijang
2011-3-28
David Young
2011-3-28
The Discrete Fourier Transform has no parameters to manipulate. The difference between the original and the reconstructed images will always be very small, though non-zero because of rounding errors.
You could explore this experimentally with test code similar to this:
imsize = 100 + ceil(1000*rand);
img = rand(imsize);
ft = fft2(img);
recon = ifft2(ft);
max(abs(img(:)-recon(:)))
which typically produces a result of order 1e-15 on my system.
1 个评论
Walter Roberson
2011-4-12
From one point of view at least, the parameter for fft would be the number of fft bins to use, and the best would be the same as the number of points along that dimension.
此问题已关闭。
关闭：
2021-8-20
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
