1## Copyright (C) 2011 Carnë Draug <carandraug+dev@gmail.com> 2## 3## This program is free software; you can redistribute it and/or modify it under 4## the terms of the GNU General Public License as published by the Free Software 5## Foundation; either version 3 of the License, or (at your option) any later 6## version. 7## 8## This program is distributed in the hope that it will be useful, but WITHOUT 9## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10## FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 11## details. 12## 13## You should have received a copy of the GNU General Public License along with 14## this program; if not, see <http://www.gnu.org/licenses/>. 15 16## -*- texinfo -*- 17## @deftypefn {Function File} {@var{out} =} imdivide (@var{a}, @var{b}) 18## @deftypefnx {Function File} {@var{out} =} imdivide (@var{a}, @var{b}, @var{class}) 19## Divide image by another image or constant. 20## 21## If @var{a} and @var{b} are two images of same size and class, @var{a} is divided 22## by @var{b}. Alternatively, if @var{b} is a floating-point scalar, @var{a} is divided 23## by it. 24## 25## The class of @var{out} will be the same as @var{a} unless @var{a} is logical 26## in which case @var{out} will be double. Alternatively, it can be 27## specified with @var{class}. 28## 29## @emph{Note}: the values are truncated to the mininum value of the output 30## class. 31## @seealso{imabsdiff, imadd, imcomplement, immultiply, imlincomb, imsubtract} 32## @end deftypefn 33 34function img = imdivide (img, val, out_class = class (img)) 35 36 if (nargin < 2 || nargin > 3) 37 print_usage; 38 endif 39 [img, val] = imarithmetics ("imdivide", img, val, out_class); 40 41 ## matlab doesn't even gives a warning in this situation, it simply returns 42 ## a double precision float 43 if (nargin > 2 && strcmpi (out_class, "logical")) 44 warning ("Ignoring request to return logical as output of division."); 45 endif 46 47 warning ("off", "Octave:divide-by-zero", "local"); 48 img = img ./ val; 49 50endfunction 51 52%!assert (imdivide (uint8 ([23 250]), uint8 ([ 2 50])), uint8 ([ 12 5])); # default to first class 53%!assert (imdivide (uint8 ([56 255]), uint8 ([ 0 0])), uint8 ([255 255])); # dividing by zero works (tested in matlab) 54%!assert (imdivide (uint8 ([23 250]), 2), uint8 ([ 12 125])); # works subtracting a scalar 55%!assert (imdivide (uint8 ([23 250]), uint8 ([ 2 50]), "uint16"), uint16 ([ 12 5])); # defining output class works (not in matlab) 56%!assert (imdivide (logical ([1 1 0 0]), logical ([1 0 1 0])), double ([1 Inf 0 NaN])); # dividing logical matrix (tested in matlab) 57%!fail ("imdivide (uint8 ([23 250]), uint16 ([23 250]))"); # input needs to have same class 58