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#-----------------------------------------------------------------------
#Copyright 2013 Centrum Wiskunde & Informatica, Amsterdam
#
#Author: Daniel M. Pelt
#Contact: D.M.Pelt@cwi.nl
#Website: http://dmpelt.github.io/pyastratoolbox/
#
#
#This file is part of the Python interface to the
#All Scale Tomographic Reconstruction Antwerp Toolbox ("ASTRA Toolbox").
#
#The Python interface to the ASTRA Toolbox 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.
#
#The Python interface to the ASTRA Toolbox 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.
#
#You should have received a copy of the GNU General Public License
#along with the Python interface to the ASTRA Toolbox. If not, see <http://www.gnu.org/licenses/>.
#
#-----------------------------------------------------------------------

def clipCircle(img):
	cdef int i,j
	cdef double x2,y2,mid,bnd
	cdef long sz,sz2
	sz = img.shape[0]
	sz2 = sz*sz
	bnd = sz2/4.
	mid = (sz-1.)/2.
	nDel=0
	for i in range(sz):
		for j in range(sz):
			x2 = (i-mid)*(i-mid)
			y2 = (j-mid)*(j-mid)
			if x2+y2>bnd:
				img[i,j]=0
				nDel=nDel+1
	return nDel