Mercurial > octave-nkf
annotate scripts/image/cmpermute.m @ 15515:4beb3a4bd440
rgbplot.m, cmpermute.m, cmunique.m, ind2rgb.m, imwrite.m: use core iscolormap function
| author | Carnë Draug <carandraug+dev@gmail.com> |
|---|---|
| date | Fri, 12 Oct 2012 23:11:08 +0200 |
| parents | 0ba7be7fed1c |
| children | d1285ebe60ca |
| rev | line source |
|---|---|
| 14896 | 1 ## Copyright (C) 2004 Josep Mones i Teixidor |
| 2 ## Copyright (C) 2012 Rik Wehbring | |
| 3 ## | |
| 4 ## This file is part of Octave. | |
| 5 ## | |
| 6 ## Octave is free software; you can redistribute it and/or modify it | |
| 7 ## under the terms of the GNU General Public License as published by | |
| 8 ## the Free Software Foundation; either version 3 of the License, or (at | |
| 9 ## your option) any later version. | |
| 10 ## | |
| 11 ## Octave is distributed in the hope that it will be useful, but | |
| 12 ## WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 13 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 14 ## General Public License for more details. | |
| 15 ## | |
| 16 ## You should have received a copy of the GNU General Public License | |
| 17 ## along with Octave; see the file COPYING. If not, see | |
| 18 ## <http://www.gnu.org/licenses/>. | |
| 19 | |
| 20 ## -*- texinfo -*- | |
| 21 ## @deftypefn {Function File} {[@var{Y}, @var{newmap}] =} cmpermute (@var{X}, @var{map}) | |
| 22 ## @deftypefnx {Function File} {[@var{Y}, @var{newmap}] =} cmpermute (@var{X}, @var{map}, @var{index}) | |
| 23 ## Reorder colors in a colormap. | |
| 24 ## | |
| 25 ## When called with only two arguments, @code{cmpermute} randomly rearranges | |
| 26 ## the colormap @var{map} and returns a new colormap @var{newmap}. It also | |
| 27 ## returns the indexed image @var{Y} which is the equivalent of the original | |
| 28 ## input image @var{X} when displayed using @var{newmap}. The input image | |
| 29 ## @var{X} must be an indexed image of class uint8 or double. | |
| 30 ## | |
| 31 ## When called with an optional third argument the order of colors in the | |
| 32 ## new colormap is defined by @var{index}. | |
| 33 ## | |
| 34 ## @strong{Caution:} @code{index} should not have repeated elements or the | |
| 35 ## function will fail. | |
| 36 ## | |
| 37 ## @end deftypefn | |
| 38 | |
| 39 ## Author: Josep Mones i Teixidor <jmones@puntbarra.com> | |
| 40 | |
| 41 function [Y, newmap] = cmpermute (X, map, index) | |
| 42 | |
| 43 if (nargin < 2 || nargin > 3) | |
| 44 print_usage (); | |
| 45 endif | |
| 46 | |
| 47 ## FIXME: Matlab only accepts 2 types. Expand to uint16 & single?? | |
| 48 if (! (isa (X, "uint8") || isa (X, "double"))) | |
| 49 error ("cmpermute: X must be of class uint8 or double"); | |
| 50 endif | |
| 51 | |
| 52 if (! isreal (X) || issparse (X) | |
| 53 || (isfloat (X) && (any (X(:) < 1 || any (X(:) != fix (X(:))))))) | |
| 54 error ("cmpermute: X must be an indexed image"); | |
| 55 endif | |
| 56 | |
|
15515
4beb3a4bd440
rgbplot.m, cmpermute.m, cmunique.m, ind2rgb.m, imwrite.m: use core iscolormap function
Carnë Draug <carandraug+dev@gmail.com>
parents:
14896
diff
changeset
|
57 if (! iscolormap (map)) |
| 14896 | 58 error ("cmpermute: MAP must be a valid colormap"); |
| 59 endif | |
| 60 | |
| 61 if (nargin < 3) | |
| 62 index = randperm (rows (map)); | |
| 63 elseif (! isvector (index) || length (index) != rows (map)) | |
| 64 error ("cmpermute: invalid parameter INDEX"); | |
| 65 endif | |
| 66 | |
| 67 ## new colormap | |
| 68 newmap = map(index,:); | |
| 69 | |
| 70 ## build reverse index | |
| 71 rindex = zeros (size (index)); | |
| 72 rindex(index) = 1:length (index); | |
| 73 | |
| 74 ## adapt indices | |
| 75 if (isa (X, "uint8")) | |
| 76 rindex = uint8 (rindex-1); | |
| 77 ## 0-based indices | |
| 78 Y = rindex(double (X) + 1); | |
| 79 else | |
| 80 Y = rindex(X); | |
| 81 endif | |
| 82 | |
| 83 endfunction | |
| 84 | |
| 85 | |
| 86 %!demo | |
| 87 %! [Y, newmap] = cmpermute ([1:4], hot (4), 4:-1:1) | |
| 88 %! ## colormap will be arranged in reverse order (so will image) | |
| 89 | |
| 90 %!shared X, map | |
| 91 %! X = uint8 (magic (16)); | |
| 92 %! [X, map] = cmunique (X); | |
| 93 | |
| 94 %!test # random permutation, 0-based index | |
| 95 %! [Y, newmap] = cmpermute (X, map); | |
| 96 %! ## test we didn't lose colors | |
| 97 %! assert (sort (map), sortrows (newmap)); | |
| 98 %! ## test if images are equal | |
| 99 %! assert (map(double (X)+1), newmap(double (Y)+1)); | |
| 100 | |
| 101 %!test # reverse map, 0-based index | |
| 102 %! [Y, newmap] = cmpermute (X, map, rows (map):-1:1); | |
| 103 %! ## we expect a reversed colormap | |
| 104 %! assert (flipud (newmap), map); | |
| 105 %! ## we expect reversed indices in image | |
| 106 %! assert (X, max (Y(:)) - Y); | |
| 107 | |
| 108 %!shared X,map | |
| 109 %! X = uint16 (magic (20)); | |
| 110 %! [X, map] = cmunique (X); | |
| 111 | |
| 112 %!test # random permutation, 1-based index | |
| 113 %! [Y, newmap] = cmpermute (X, map); | |
| 114 %! ## test we didn't lose colors | |
| 115 %! assert (sort (map), sortrows (newmap)); | |
| 116 %! ## test if images are equal | |
| 117 %! assert (map(X), newmap(Y)); | |
| 118 | |
| 119 %!test # reverse map, 1-based index | |
| 120 %! [Y, newmap] = cmpermute (X, map, rows (map):-1:1); | |
| 121 %! ## we expect a reversed colormap | |
| 122 %! assert (newmap (rows (newmap):-1:1,:), map); | |
| 123 %! ## we expect reversed indices in image | |
| 124 %! assert (X, max (Y(:)) + 1 - Y); | |
| 125 | |
| 126 ## Test input validation | |
| 127 %!error cmpermute () | |
| 128 %!error cmpermute (1,2,3,4) | |
| 129 %!error <X must be of class uint8> cmpermute (uint16 (magic (16)), jet (256)) | |
| 130 %!error <X must be an indexed image> cmpermute (1+i, jet (256)) | |
| 131 %!error <X must be an indexed image> cmpermute (sparse (1), jet (256)) | |
| 132 %!error <X must be an indexed image> cmpermute (0, jet (256)) | |
| 133 %!error <X must be an indexed image> cmpermute (1.5, jet (256)) | |
| 134 %!error <MAP must be a valid colormap> cmpermute (1, "a") | |
| 135 %!error <MAP must be a valid colormap> cmpermute (1, i) | |
| 136 %!error <MAP must be a valid colormap> cmpermute (1, ones (3,3,3)) | |
| 137 %!error <MAP must be a valid colormap> cmpermute (1, ones (3,2)) | |
| 138 %!error <MAP must be a valid colormap> cmpermute (1, [-1 1 1]) | |
| 139 %!error <MAP must be a valid colormap> cmpermute (1, [2 1 1]) | |
| 140 %!error <invalid parameter INDEX> cmpermute (1, [0 1 0;1 0 1], ones (3)) | |
| 141 %!error <invalid parameter INDEX> cmpermute (1, [0 1 0;1 0 1], 1:3) | |
| 142 |