###########################################################################
# (C) 2016 Elettra - Sincrotrone Trieste S.C.p.A.. All rights reserved. #
# #
# #
# This file is part of STP-Core, the Python core of SYRMEP Tomo Project, #
# a software tool for the reconstruction of experimental CT datasets. #
# #
# STP-Core is free software: you can redistribute it and/or modify it #
# under the terms of the GNU General Public License as published by the #
# Free Software Foundation, either version 3 of the License, or (at your #
# option) any later version. #
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# STP-Core is distributed in the hope that it will be useful, but WITHOUT #
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or #
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License #
# for more details. #
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# You should have received a copy of the GNU General Public License #
# along with STP-Core. If not, see <http://www.gnu.org/licenses/>. #
# #
###########################################################################
#
# Author: Francesco Brun
# Last modified: July, 8th 2016
#
from numpy import fliplr, tile, concatenate
[docs]def extfov_correction(im, ext_fov, ext_fov_rot_right, ext_fov_overlap):
"""Apply sinogram correction for extended FOV acquisition mode
Parameters
----------
im : array_like
Image data (sinogram) as numpy array.
ext : bool
True if the extended FOV mode has been performed.
ext_fov_rot_right : bool
True if the extended FOV mode has been performed with rotation center
shifted to the right, left otherwise.
ext_fov_overlap : int
Number of overlapping pixels.
"""
if (ext_fov):
im_bottom = im[im.shape[0]/2:,:]
im_bottom = fliplr(im_bottom)
if (ext_fov_rot_right):
# Flip the bottom part of the sinogram and put it on the left:
if (ext_fov_overlap % 2 == 0):
im_bottom = im_bottom[:,:-ext_fov_overlap/2]
if (im.shape[0] % 2 == 0):
im = concatenate((im_bottom, im[0:im.shape[0]/2,ext_fov_overlap/2:]), axis=1)
else:
im = concatenate((im_bottom, im[0:im.shape[0]/2+1,ext_fov_overlap/2:]), axis=1)
else:
im_bottom = im_bottom[:,:-ext_fov_overlap/2 + 1]
if (im.shape[0] % 2 == 0):
im = concatenate((im_bottom, im[0:im.shape[0]/2,ext_fov_overlap/2:]), axis=1)
else:
im = concatenate((im_bottom, im[0:im.shape[0]/2+1,ext_fov_overlap/2:]), axis=1)
else:
# Flip the bottom part of the sinogram and put it on the right:
if (ext_fov_overlap % 2 == 0):
im_bottom = im_bottom[:,ext_fov_overlap/2:]
if (im.shape[0] % 2 == 0):
im = concatenate((im[0:im.shape[0]/2,:-ext_fov_overlap/2], im_bottom), axis=1)
else:
im = concatenate((im[0:im.shape[0]/2+1,:-ext_fov_overlap/2], im_bottom), axis=1)
else:
im_bottom = im_bottom[:,ext_fov_overlap/2+1:]
if (im.shape[0] % 2 == 0):
im = concatenate((im[0:im.shape[0]/2,:-ext_fov_overlap/2], im_bottom), axis=1)
else:
im = concatenate((im[0:im.shape[0]/2+1,:-ext_fov_overlap/2], im_bottom), axis=1)
return im