--- /dev/null
+## Copyright (C) 2004 Josep Mones i Teixidor
+##
+## 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 2 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} {[@var{Y}, @var{newmap}] = } cmunique (@var{X},@var{map})
+## @deftypefnx {Function File} {[@var{Y}, @var{newmap}] = } cmunique (@var{RGB})
+## @deftypefnx {Function File} {[@var{Y}, @var{newmap}] = } cmunique (@var{I})
+## Finds colormap with unique colors and corresponding image.
+##
+## @code{[Y,newmap]=cmunique(X,map)} returns an indexed image @var{y}
+## along with its associated colormap @var{newmap} equivalent (which
+## produce the same image) to supplied @var{X} and its colormap
+## @var{map}; but eliminating any repeated rows in colormap colors and
+## adjusting indices in the image matrix as needed.
+##
+## @code{[Y,newmap]=cmunique(RGB)} returns an indexed image @var{y}
+## along with its associated colormap @var{newmap} computed from a
+## true-color image @var{RGB} (a m-by-n-by-3 array), where @var{newmap}
+## is the smallest colormap possible (alhough it could be as long as
+## number of pixels in image).
+##
+## @code{[Y,newmap]=cmunique(I)} returns an indexed image @var{y}
+## along with its associated colormap @var{newmap} computed from a
+## intensity image @var{I}, where @var{newmap} is the smallest
+## colormap possible (alhough it could be as long as number of pixels
+## in image).
+##
+## @strong{Notes:}
+##
+## @var{newmap} is always a @var{m}-by-3 matrix, even if input image is
+## a intensity grey-scale image @var{I} (all three RGB planes are
+## assigned the same value).
+##
+## @var{newmap} is always of class double. If we use a RGB or intensity
+## image of class uint8 or uint16, the colors in the colormap will be of
+## class double in the range [0,1] (they are divided by intmax("uint8")
+## and intmax("uint16") respectively.
+##
+## @end deftypefn
+
+
+## Author: Josep Mones i Teixidor <jmones@puntbarra.com>
+
+function [Y, newmap] = cmunique(P1, P2)
+ if (nargin<1 || nargin>2)
+ usage("[Y, newmap] = cmunique(X, map), [Y, newmap] = cmunique(RGB), [Y, newmap] = cmunique(I)");
+ endif
+
+
+ if(nargin==2)
+ ## (X, map) case
+ [newmap,i,j]=unique(P2,'rows'); ## calculate unique colormap
+ if(isa(P1,"double"))
+ Y=j(P1); ## find new indices
+ else
+ Y=j(double(P1)+1); ## find new indices
+ endif
+ else
+ switch(size(P1,3))
+ case(1)
+ ## I case
+ [newmap,i,j]=unique(P1); ## calculate unique colormap
+ newmap=repmat(newmap,1,3); ## get a RGB colormap
+ Y=reshape(j,rows(P1),columns(P1)); ## Y is j reshaped
+ case(3)
+ ## RGB case
+ map=[P1(:,:,1)(:), P1(:,:,2)(:), P1(:,:,3)(:)]; ## build a map with all values
+ [newmap,i,j]=unique(map, 'rows'); ## calculate unique colormap
+ Y=reshape(j,rows(P1),columns(P1)); ## Y is j reshaped
+ otherwise
+ error("cmunique: first parameter is invalid.");
+ endswitch
+
+ ## if image was uint8 or uint16 we have to convert newmap to [0,1] range
+ if(!isa(P1,"double"))
+ newmap=double(newmap)/double(intmax(class(P1)));
+ endif
+ endif
+
+ if(rows(newmap)<=256)
+ ## convert Y to uint8 (0-based indices then)
+ Y=uint8(Y-1);
+ endif
+
+
+endfunction
+
+
+%!demo
+%! [Y,newmap]=cmunique([1:4;5:8],[hot(4);hot(4)])
+%! # Both rows are equal since map maps colors to the same value
+%! # cmunique will give the same indices to both
+
+
+%!# This triggers invalid first parameter
+%!error(cmunique(zeros(3,3,2)));
+
+%!# Check that output is uint8 in short colormaps
+%!test
+%! [Y,newmap]=cmunique([1:4;5:8], [hot(4);hot(4)]);
+%! assert(Y,uint8([0:3;0:3]));
+%! assert(newmap,hot(4));
+
+%!# Check that output is double in bigger
+%!test
+%! [Y,newmap]=cmunique([1:300;301:600], [hot(300);hot(300)]);
+%! assert(Y,[1:300;1:300]);
+%! assert(newmap,hot(300));
+
+%!# Check boundary case 256
+%!test
+%! [Y,newmap]=cmunique([1:256;257:512], [hot(256);hot(256)]);
+%! assert(Y,uint8([0:255;0:255]));
+%! assert(newmap,hot(256));
+
+%!# Check boundary case 257
+%!test
+%! [Y,newmap]=cmunique([1:257;258:514], [hot(257);hot(257)]);
+%! assert(Y,[1:257;1:257]);
+%! assert(newmap,hot(257));
+
+%!# Random RGB image
+%!test
+%! RGB=rand(10,10,3);
+%! [Y,newmap]=cmunique(RGB);
+%! assert(RGB(:,:,1),newmap(:,1)(Y+1));
+%! assert(RGB(:,:,2),newmap(:,2)(Y+1));
+%! assert(RGB(:,:,3),newmap(:,3)(Y+1));
+
+%!# Random uint8 RGB image
+%!test
+%! RGB=uint8(rand(10,10,3)*255);
+%! RGBd=double(RGB)/255;
+%! [Y,newmap]=cmunique(RGB);
+%! assert(RGBd(:,:,1),newmap(:,1)(Y+1));
+%! assert(RGBd(:,:,2),newmap(:,2)(Y+1));
+%! assert(RGBd(:,:,3),newmap(:,3)(Y+1));
+
+%!# Random uint16 RGB image
+%!test
+%! RGB=uint16(rand(10,10,3)*65535);
+%! RGBd=double(RGB)/65535;
+%! [Y,newmap]=cmunique(RGB);
+%! assert(RGBd(:,:,1),newmap(:,1)(Y+1));
+%! assert(RGBd(:,:,2),newmap(:,2)(Y+1));
+%! assert(RGBd(:,:,3),newmap(:,3)(Y+1));
+
+%!# Random I image
+%!test
+%! I=rand(10,10);
+%! [Y,newmap]=cmunique(I);
+%! assert(I,newmap(:,1)(Y+1));
+%! assert(I,newmap(:,2)(Y+1));
+%! assert(I,newmap(:,3)(Y+1));
+
+%!# Random uint8 I image
+%!test
+%! I=uint8(rand(10,10)*256);
+%! Id=double(I)/255;
+%! [Y,newmap]=cmunique(I);
+%! assert(Id,newmap(:,1)(Y+1));
+%! assert(Id,newmap(:,2)(Y+1));
+%! assert(Id,newmap(:,3)(Y+1));
+
+%!# Random uint16 I image
+%!test
+%! I=uint16(rand(10,10)*65535);
+%! Id=double(I)/65535;
+%! [Y,newmap]=cmunique(I);
+%! assert(Id,newmap(:,1)(Y+1));
+%! assert(Id,newmap(:,2)(Y+1));
+%! assert(Id,newmap(:,3)(Y+1));
+
+%
+% $Log$
+% Revision 1.3 2007/03/23 16:14:36 adb014
+% Update the FSF address
+%
+% Revision 1.2 2007/01/04 23:44:22 hauberg
+% Minor changes in help text
+%
+% Revision 1.1 2006/08/20 12:59:32 hauberg
+% Changed the structure to match the package system
+%
+% Revision 1.4 2004/09/08 16:06:31 jmones
+% Solved problem with uint8 indexing and reduced tests on types (suggested by P. Kienzle)
+%
+% Revision 1.3 2004/09/03 17:07:26 jmones
+% Support for uint8 and uint16 types added.
+%
+% Revision 1.2 2004/08/17 15:48:03 jmones
+% Clarified expected data for RGB images in doc
+%
+% Revision 1.1 2004/08/17 15:45:40 jmones
+% cmunique: Finds colormap with unique colors and corresponding image
+%
+%
+
+
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff