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* bwlabeln.cc (bwlabel_nd): Fix small bug in comment
| author | Jordi Gutiérrez Hermoso <jordigh@octave.org> |
|---|---|
| date | Tue, 18 Nov 2014 11:30:57 -0500 |
| parents | eb027eb95855 |
| children |
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## Copyright (C) 2005 Carvalho-Mariel ## Copyright (C) 2010-2013 Carnë Draug <carandraug@octave.org> ## ## This program 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. ## ## This program 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 ## this program; if not, see <http://www.gnu.org/licenses/>. ## -*- texinfo -*- ## @deftypefn {Function File} {} imbothat (@var{img}, @var{SE}) ## Perform morphological bottom hat filtering. ## ## The matrix @var{img} must be numeric while @var{SE} can be a: ## @itemize @bullet ## @item ## strel object; ## @item ## array of strel objects as returned by `@@strel/getsequence'; ## @item ## matrix of 0's and 1's. ## @end itemize ## ## A bottom hat transform corresponds to the difference between the closing ## of @var{img} and @var{img} itself, i.e., it is equivalent to: ## @example ## imclose (img, se) - img; ## @end example ## ## A bottom-hat transform is also known as 'black', or 'closing', top-hat ## transform. ## ## @seealso{imerode, imdilate, imopen, imclose, imtophat, mmgradm} ## @end deftypefn function black = imbothat (img, se) if (nargin != 2) print_usage (); elseif (! isimage (img)) error("imbothat: IMG must be a numeric matrix"); endif se = prepare_strel ("imbothat", se); ## Perform filtering ## Note that in case that the transform is to applied to a logical image, ## subtraction must be handled in a different way (x & !y) instead of (x - y) ## or it will return a double precision matrix if (islogical (img)) black = imclose (img, se) & ! img; else black = imclose (img, se) - img; endif endfunction %!assert (imbothat (ones (3), [1 1; 0 1]), zeros (3)); %!assert (imbothat (true (3), [1 1; 0 1]), false (3)); %!shared in, out, se %! in = [ 0 0 0 1 1 1 0 0 1 1 %! 0 1 0 1 1 1 0 0 0 1 %! 1 1 1 1 1 0 0 0 0 0 %! 0 1 1 1 1 0 0 0 0 0 %! 0 0 0 1 0 0 0 0 1 0 %! 0 0 0 0 0 0 0 1 1 1 %! 0 0 0 0 1 0 1 0 1 0 %! 0 0 0 1 1 1 1 1 0 0 %! 0 0 0 0 1 1 1 0 0 0 %! 0 0 0 1 1 1 0 0 0 0]; %! %! out = [ 1 1 1 0 0 0 1 1 0 0 %! 1 0 1 0 0 0 0 0 0 0 %! 0 0 0 0 0 0 0 0 0 1 %! 1 0 0 0 0 0 0 0 0 1 %! 0 0 0 0 1 0 0 0 0 1 %! 0 0 0 1 1 1 1 0 0 0 %! 0 0 0 1 0 1 0 1 0 1 %! 0 0 0 0 0 0 0 0 0 0 %! 0 0 0 1 0 0 0 0 0 0 %! 0 0 0 0 0 0 1 0 0 0]; %!assert (imbothat (logical (in), ones (3)), logical (out)); %! %! out = [ 7 0 15 8 1 6 0 13 6 24 %! 0 8 9 2 0 0 16 7 0 23 %! 89 7 0 41 39 7 12 7 0 23 %! 8 1 69 40 58 1 6 2 0 43 %! 7 0 63 59 52 0 0 0 14 32 %! 62 55 6 7 0 7 0 23 16 1 %! 56 74 0 2 0 0 16 14 7 0 %! 0 73 69 0 0 19 15 8 1 0 %! 8 6 0 0 6 13 9 2 0 6 %! 7 0 0 19 0 14 7 0 23 0]; %!assert (imbothat (magic (10), ones (3)), out); %!assert (imbothat (uint8 (magic (10)), strel ("square", 3)), uint8 (out)); %! %! ## using a se that will be decomposed in 2 pieces %! out =[ 7 0 87 66 59 7 0 19 12 30 %! 0 13 81 60 58 1 19 13 6 29 %! 89 12 0 54 52 20 18 7 0 23 %! 8 6 69 53 71 14 12 2 0 43 %! 7 0 63 73 66 14 7 0 23 41 %! 76 69 14 7 0 30 23 46 39 7 %! 70 88 9 2 0 24 42 40 33 6 %! 14 87 80 0 0 43 41 34 27 0 %! 84 82 0 0 19 37 35 28 26 19 %! 89 82 0 20 13 36 29 22 45 13]; %!assert (imbothat (magic (10), ones(5)), out); %! %! ## using a weird non-symmetric and even-size se %! out =[ 0 0 15 8 1 3 0 7 0 18 %! 0 8 53 59 0 0 14 13 0 17 %! 84 0 0 40 38 6 13 6 0 23 %! 2 0 42 47 58 0 6 0 0 41 %! 0 0 62 59 52 0 0 0 16 35 %! 6 58 13 6 0 3 19 19 35 1 %! 0 18 0 0 0 0 15 13 6 0 %! 0 17 69 0 0 17 17 8 0 0 %! 8 67 0 0 0 15 9 2 0 6 %! 7 0 0 17 10 42 7 0 19 0]; %!assert (imbothat (magic (10), [1 0 0 0; 1 1 1 0; 0 1 0 1]), out); %! %! ## N dimensional and weird se %! in = reshape (magic(16), [4 8 4 2]); %! se = ones (3, 3, 3); %! se(:,:,1) = [1 0 1; 0 1 1; 0 0 0]; %! se(:,:,3) = [1 0 1; 0 1 1; 0 0 1]; %! out = zeros (size (in)); %! out(:,:,1,1) = [ %! 0 17 81 145 237 146 64 0 %! 205 128 64 0 0 37 83 147 %! 175 111 47 0 0 64 117 181 %! 0 64 128 209 173 109 45 0]; %! out(:,:,2,1) = [ %! 235 142 78 18 0 23 69 133 %! 0 35 103 163 215 128 46 0 %! 0 64 128 195 183 123 48 0 %! 153 93 43 0 14 78 146 215]; %! out(:,:,3,1) = [ %! 0 25 89 153 229 142 64 0 %! 201 128 64 0 0 41 91 155 %! 167 103 57 0 0 64 125 189 %! 0 64 146 217 165 101 37 0]; %! out(:,:,4,1) = [ %! 227 142 78 14 0 31 77 141 %! 0 43 107 171 211 128 46 0 %! 0 64 128 203 179 115 48 0 %! 149 99 35 0 18 82 146 223]; %! out(:,:,1,2) = [ %! 0 33 97 161 221 146 64 0 %! 189 125 61 0 0 53 99 163 %! 159 95 31 0 0 64 128 197 %! 0 64 128 225 157 93 29 0]; %! out(:,:,2,2) = [ %! 219 142 78 18 0 39 85 149 %! 0 51 119 179 199 128 46 0 %! 0 64 128 211 167 107 43 0 %! 137 77 27 0 14 78 146 231]; %! out(:,:,3,2) = [ %! 0 41 105 169 213 142 64 0 %! 185 121 64 0 0 57 107 171 %! 151 87 41 0 0 64 128 205 %! 0 64 146 233 149 85 21 0]; %! out(:,:,4,2) = [ %! 211 142 78 14 0 47 93 157 %! 0 59 123 187 195 128 46 0 %! 0 64 128 219 163 99 35 0 %! 133 83 19 0 18 82 146 239]; %!assert (imbothat (in, se), out);