[問題] 關於wiener filter 裡的 psf2otf ?
想請問各位有做影像修正的大大，小弟最近在lab裡解決如何deconv加雜訊了訊號
讀了paper試了幾種deconv方法，像Jansson、Wiener、L-R等等在study wiener時
發現，內建deconvwnr指令一開始有執行一行指令 H = psf2otf(PSF, sizeI)
從名稱來看是轉換psf函數成otf函數，查了一下定義otf函數是psf函數的頻域
再把psf2otf打開看，發現中間有段...
--------------------------------------------------------------------
% Circularly shift otf so that the "center" of the PSF is at the
% (1,1) element of the array.
psf = circshift(psf,-floor(psfSize/2));
% Compute the OTF
otf = fftn(psf);
---------------------------------------------------------------------
它把輸入訊號psf做循環移位1/2長度，結果似乎在消除出輸出輸入之間的phase
delay?小弟這種理解不知有無錯誤，有人知道為何要如此位移嘛?謝謝!
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