matlab中ifft2怎么用，里面的参数怎么设置？想要计算一个二维的反傅里叶变换 如何将彩色图像用Matlab进行傅里叶变换，再反变换回去？
\u5173\u4e8e\u4e8c\u7ef4\u5085\u91cc\u53f6\u53d8\u6362 matlabY = fft2(X,m,n)
\u8fd9\u6837\u53ef\u4ee5\u4f7f\u8f93\u51fa\u7684Y\u77e9\u9635\u662fm\u884cn\u5217\u7684
\u56fe\u50cf\u4ee5im\u4ee3\u66ff
r = im(:, :, 1);
g = im(:, :, 2);
b = im(:, :, 3);
fr = fft2(r); %\u5085\u91cc\u53f6\u53d8\u6362
fg = fft2(g);
fb = fft2(b);
or = ifft2(fr); %\u5085\u91cc\u53f6\u53cd\u53d8\u6362
og = ifft2(fg);
ob = ifft2(fb);
out(:, :, 1) = real(or);
out(:, :, 2) = real(og);
out(:, :, 3) = real(ob);
imshow(out) %out\u5c31\u662f\u53cd\u53d8\u6362\u56de\u53bb\u7684\u56fe\u50cf\uff0c\u5982\u679c\u6ca1\u51fa\u9519\uff0c\u663e\u793a\u51fa\u6765\u7684out\u5e94\u8be5\u4e0eim\u4e00\u6837
比如你要反变换的图像放到了矩阵I里
那么只要 H=ifft2（I）；就行了
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