[英]Matlab's ifft2 function in OpenCV
我已經在互聯網上進行了很多搜索,但仍未找到解決方案。 我想要的是將Matlab的ifft2
函數轉換為OpenCV,以獲得相同的結果。 例如,如果我有一個10x10
矩陣A
:
A =
11 22 33 1 1 1 1 1 1 1
44 55 66 1 1 1 1 1 1 1
77 88 99 1 1 1 1 1 1 1
100 111 122 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
然后在Matlab中,調用ifft2(A)
給我以下信息:
ans =
9.1600 + 0.0000i 5.4570 + 4.6041i 0.5640 + 4.4443i -1.1170 + 0.7295i 1.0560 - 1.4066i 2.7200 + 0.0000i 1.0560 + 1.4066i -1.1170 - 0.7295i 0.5640 - 4.4443i 5.4570 - 4.6041i
1.7274 + 6.5730i -2.5500 + 5.5266i -3.6046 + 1.6030i -1.0629 - 0.6619i 1.2068 + 0.5078i 0.5758 + 2.1910i -0.9060 + 1.3047i 0.2070 - 0.8463i 3.4605 - 0.4030i 4.7141 + 3.3760i
-3.6507 + 1.1351i -3.2357 - 1.1758i -1.1907 - 1.8927i 0.1292 - 0.6560i -0.3480 + 0.5913i -1.2169 + 0.3784i -0.8219 - 0.3575i 0.2811 + 0.1882i 0.0968 + 1.8925i -1.8722 + 2.6341i
0.6876 - 1.9331i 1.4480 - 0.9227i 0.9832 + 0.1199i 0.0550 + 0.1593i -0.1955 - 0.4607i 0.2292 - 0.6444i 0.3196 - 0.1496i -0.3841 + 0.0821i -1.0290 - 0.6749i -0.5821 - 1.7727i
1.1457 + 1.6084i -0.1392 + 1.7632i -0.8331 + 0.7911i -0.3628 - 0.0938i 0.3857 + 0.0000i 0.3819 + 0.5361i -0.1268 + 0.4468i -0.0493 - 0.2667i 0.8930 - 0.4889i 1.6339 + 0.4186i
-1.6800 + 0.0000i -1.1861 - 0.8618i -0.2800 - 0.8618i 0.0661 - 0.2034i -0.2800 + 0.2034i -0.5600 + 0.0000i -0.2800 - 0.2034i 0.0661 + 0.2034i -0.2800 + 0.8618i -1.1861 + 0.8618i
1.1457 - 1.6084i 1.6339 - 0.4186i 0.8930 + 0.4889i -0.0493 + 0.2667i -0.1268 - 0.4468i 0.3819 - 0.5361i 0.3857 - 0.0000i -0.3628 + 0.0938i -0.8331 - 0.7911i -0.1392 - 1.7632i
0.6876 + 1.9331i -0.5821 + 1.7727i -1.0290 + 0.6749i -0.3841 - 0.0821i 0.3196 + 0.1496i 0.2292 + 0.6444i -0.1955 + 0.4607i 0.0550 - 0.1593i 0.9832 - 0.1199i 1.4480 + 0.9227i
-3.6507 - 1.1351i -1.8722 - 2.6341i 0.0968 - 1.8925i 0.2811 - 0.1882i -0.8219 + 0.3575i -1.2169 - 0.3784i -0.3480 - 0.5913i 0.1292 + 0.6560i -1.1907 + 1.8927i -3.2357 + 1.1758i
1.7274 - 6.5730i 4.7141 - 3.3760i 3.4605 + 0.4030i 0.2070 + 0.8463i -0.9060 - 1.3047i 0.5758 - 2.1910i 1.2068 - 0.5078i -1.0629 + 0.6619i -3.6046 - 1.6030i -2.5500 - 5.5266i
在OpenCV中,我編寫了以下代碼(感謝Internet), 實際上實現了與 Matlab 相同的結果 。
cv::Mat inverseDFT;
cv::Mat planes[] = { cv::Mat_<float>(input), cv::Mat::zeros(input.size(), CV_32F) };
cv::Mat complex;
cv::merge(planes, 2, complex);
cv::idft(complex, inverseDFT, cv::DFT_SCALE | cv::DFT_INVERSE);
到目前為止,這很好。 但是 ,當我使用另一個具有相同類型和值的大小為82x82
的矩陣時,Matlab的結果與OpenCV的結果有很大不同。 這是Matlab的輸出(前兩行):
1.0e+05 *
[-0.0000 -9.6761 -4.6365 1.8979 1.4972 -0.0025 0.1037 -0.0919 0.3140 0.0032 0.0195 0.0057 -0.0002 0.0147 -0.0023 0.0088 0.0045 -0.0023 0.0135;
-0.6180 4.6026 1.9042 -1.0747 -0.5034 -0.0088 -0.0466 0.0479 -0.1339 -0.0019 -0.0078 -0.0019 -0.0031 -0.0098 0.0009 -0.0038 -0.0053 0.0034 -0.0070;
....]
這是OpenCV結果(前兩行):
[15.8347 148.3 15.5297 148.068 15.3074 147.476 15.1266 146.854 14.9336 146.121 14.649 145.361 14.4584 144.357 14.1337 143.344 13.8938 142.052 13.4711 140.892 12.9521 139.762 12.3772 138.7 11.7153 137.773 11.149 136.736 10.6333 136.07 10.0025 135.68 9.35163 135.744 8.37026 136.085 7.51313 136.597 6.65663 137.297 5.84039 138.144 5.08981 138.964 4.2696 139.838 3.93125 140.847 3.83195 141.894 4.0224 142.883 4.54194 143.872 5.35709 144.933 6.18112 145.637 6.97564 146.306 7.91474 146.833 8.90979 147.268 9.90416 147.69 10.7855 147.929 11.9145 148.177 13.3188 148.587 14.5545 148.747 15.3029 148.96 15.8501 149.022 16.1713 149.002 16.0789 148.678 ;
83.1579 -72.1501 83.2033 -72.3991 83.0443 -72.9689 83.028 -73.201 82.9732 -73.2787 82.9527 -73.2777 83.039 -73.2688 83.2974 -73.331 83.7781 -73.6298 84.5012 -73.8774 85.2545 -74.02 86.2663 -74.1823 87.4866 -74.3593 88.8467 -74.474 90.3635 -74.5438 91.6828 -74.5036 92.9061 -73.9815 93.1934 -73.0743 93.4254 -72.1992 93.1917 -71.2198 92.45 -70.201 91.1874 -69.4783 89.0805 -68.5612 87.2752 -67.461 85.2434 -66.3476 83.1033 -65.316 80.9829 -64.4404 79.0108 -63.7758 77.3056 -63.3485 75.7612 -63.1322 74.7189 -63.3549 74.1633 -63.9313 74.1057 -64.8886 74.2431 -66.0125 74.9995 -66.9026 76.9265 -67.4861 78.861 -68.5714 80.1996 -69.2898 81.3412 -70.1617 82.2211 -70.9372 82.7735 -71.4485;
....]
是什么導致了這種差異? 有人可以幫忙嗎? 謝謝。
實際上,在Matlab中fft是離散傅里葉變換,我發現可以通過OpenCV的dct達到相同的輸出
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.