PSF: increased PSF application performance

Signed-off-by: Nicola Vigano <nicola.vigano@esrf.fr>

zUtil_Imaging/GtPSF.m

@@ -135,8 +135,8 @@ classdef GtPSF < handle
             otf = fft(otf, [], 1);
             otf = fft(otf, [], 3);
 
-            otf = fftshift(otf, 1);
-            otf = fftshift(otf, 3);
+%             otf = fftshift(otf, 1);
+%             otf = fftshift(otf, 3);
         end
 
         function init_otfs(self)
@@ -186,8 +186,8 @@ classdef GtPSF < handle
             imgs = fft(imgs, [], 1);
             imgs = fft(imgs, [], 3);
 
-            imgs = fftshift(imgs, 1);
-            imgs = fftshift(imgs, 3);
+%             imgs = fftshift(imgs, 1);
+%             imgs = fftshift(imgs, 3);
 
             if (is_direct || self.is_symmetric)
                 imgs = bsxfun(@times, imgs, self.otf_direct);
@@ -195,17 +195,17 @@ classdef GtPSF < handle
                 imgs = bsxfun(@times, imgs, self.otf_adjoint);
             end
 
-            imgs = ifftshift(imgs, 1);
-            imgs = ifftshift(imgs, 3);
+%             imgs = ifftshift(imgs, 1);
+%             imgs = ifftshift(imgs, 3);
 
             imgs = ifft(imgs, [], 1);
             imgs = ifft(imgs, [], 3);
 
+            imgs = real(imgs);
+
             imgs = fftshift(imgs, 1);
             imgs = fftshift(imgs, 3);
 
-            imgs = real(imgs);
-
             imgs = imgs((self.otf_padding+1):(end-self.otf_padding), :, ...
                 (self.otf_padding+1):(end-self.otf_padding));
         end