Mercurial > octave-nkf
view scripts/image/rgb2ind.m @ 17281:bc924baa2c4e
doc: Add new @qcode macro for code samples which are quoted.
Macro handles options ("on") or properties ("position") more elegantly
than @code{"text"}.
* doc/interpreter/macros.texi: Add new @qcode macro.
* doc/interpreter/tips.txi: Add documentation about @qcode macro.
* doc/interpreter/basics.txi, doc/interpreter/container.txi,
doc/interpreter/emacs.txi, doc/interpreter/errors.txi,
doc/interpreter/eval.txi, doc/interpreter/expr.txi,
doc/interpreter/external.txi, doc/interpreter/func.txi,
doc/interpreter/grammar.txi, doc/interpreter/image.txi,
doc/interpreter/install.txi, doc/interpreter/interp.txi,
doc/interpreter/io.txi, doc/interpreter/matrix.txi,
doc/interpreter/numbers.txi, doc/interpreter/oop.txi,
doc/interpreter/package.txi, doc/interpreter/plot.txi,
doc/interpreter/quad.txi, doc/interpreter/sparse.txi,
doc/interpreter/strings.txi, doc/interpreter/system.txi,
doc/interpreter/vectorize.txi, libinterp/corefcn/balance.cc,
libinterp/corefcn/bitfcns.cc, libinterp/corefcn/cellfun.cc,
libinterp/corefcn/conv2.cc, libinterp/corefcn/data.cc,
libinterp/corefcn/debug.cc, libinterp/corefcn/defaults.cc,
libinterp/corefcn/dirfns.cc, libinterp/corefcn/dlmread.cc,
libinterp/corefcn/error.cc, libinterp/corefcn/file-io.cc,
libinterp/corefcn/find.cc, libinterp/corefcn/gammainc.cc,
libinterp/corefcn/graphics.cc, libinterp/corefcn/help.cc,
libinterp/corefcn/hex2num.cc, libinterp/corefcn/input.cc,
libinterp/corefcn/load-path.cc, libinterp/corefcn/load-save.cc,
libinterp/corefcn/ls-oct-ascii.cc, libinterp/corefcn/lu.cc,
libinterp/corefcn/luinc.cc, libinterp/corefcn/matrix_type.cc,
libinterp/corefcn/oct-hist.cc, libinterp/corefcn/pager.cc,
libinterp/corefcn/pr-output.cc, libinterp/corefcn/pt-jit.cc,
libinterp/corefcn/qz.cc, libinterp/corefcn/rand.cc,
libinterp/corefcn/regexp.cc, libinterp/corefcn/schur.cc,
libinterp/corefcn/sighandlers.cc, libinterp/corefcn/sparse.cc,
libinterp/corefcn/spparms.cc, libinterp/corefcn/str2double.cc,
libinterp/corefcn/svd.cc, libinterp/corefcn/symtab.cc,
libinterp/corefcn/syscalls.cc, libinterp/corefcn/toplev.cc,
libinterp/corefcn/tril.cc, libinterp/corefcn/typecast.cc,
libinterp/corefcn/utils.cc, libinterp/corefcn/variables.cc,
libinterp/dldfcn/__init_fltk__.cc, libinterp/dldfcn/chol.cc,
libinterp/dldfcn/colamd.cc, libinterp/dldfcn/fftw.cc, libinterp/dldfcn/qr.cc,
libinterp/dldfcn/symbfact.cc, libinterp/octave-value/ov-base.cc,
libinterp/octave-value/ov-fcn-handle.cc,
libinterp/octave-value/ov-fcn-inline.cc, libinterp/octave-value/ov-java.cc,
libinterp/octave-value/ov-range.cc, libinterp/octave-value/ov-struct.cc,
libinterp/octave-value/ov-usr-fcn.cc, libinterp/parse-tree/oct-parse.in.yy,
libinterp/parse-tree/pt-binop.cc, libinterp/parse-tree/pt-eval.cc,
libinterp/parse-tree/pt-mat.cc, scripts/@ftp/ftp.m,
scripts/deprecated/java_convert_matrix.m, scripts/deprecated/java_debug.m,
scripts/deprecated/java_unsigned_conversion.m, scripts/deprecated/shell_cmd.m,
scripts/general/dblquad.m, scripts/general/display.m,
scripts/general/genvarname.m, scripts/general/idivide.m,
scripts/general/interp1.m, scripts/general/interp2.m,
scripts/general/interp3.m, scripts/general/interpn.m, scripts/general/isa.m,
scripts/general/profexplore.m, scripts/general/profile.m,
scripts/general/quadgk.m, scripts/general/randi.m, scripts/general/structfun.m,
scripts/general/subsindex.m, scripts/general/triplequad.m,
scripts/geometry/griddata.m, scripts/geometry/griddata3.m,
scripts/geometry/griddatan.m, scripts/geometry/voronoi.m, scripts/help/help.m,
scripts/help/lookfor.m, scripts/image/cmpermute.m, scripts/image/colormap.m,
scripts/image/image.m, scripts/image/imagesc.m, scripts/image/imfinfo.m,
scripts/image/imformats.m, scripts/image/imread.m, scripts/image/imshow.m,
scripts/image/imwrite.m, scripts/image/ind2gray.m, scripts/image/lines.m,
scripts/image/rgb2ind.m, scripts/image/spinmap.m, scripts/io/dlmwrite.m,
scripts/io/strread.m, scripts/io/textread.m, scripts/io/textscan.m,
scripts/java/javaclasspath.m, scripts/java/usejava.m,
scripts/miscellaneous/bzip2.m, scripts/miscellaneous/computer.m,
scripts/miscellaneous/copyfile.m, scripts/miscellaneous/debug.m,
scripts/miscellaneous/dos.m, scripts/miscellaneous/edit.m,
scripts/miscellaneous/gzip.m, scripts/miscellaneous/license.m,
scripts/miscellaneous/mkoctfile.m, scripts/miscellaneous/movefile.m,
scripts/miscellaneous/parseparams.m, scripts/miscellaneous/unix.m,
scripts/optimization/fminbnd.m, scripts/optimization/fminsearch.m,
scripts/optimization/fminunc.m, scripts/optimization/fsolve.m,
scripts/optimization/fzero.m, scripts/optimization/glpk.m,
scripts/optimization/lsqnonneg.m, scripts/optimization/optimset.m,
scripts/optimization/pqpnonneg.m, scripts/pkg/pkg.m, scripts/plot/allchild.m,
scripts/plot/ancestor.m, scripts/plot/area.m, scripts/plot/axis.m,
scripts/plot/bar.m, scripts/plot/barh.m, scripts/plot/box.m,
scripts/plot/caxis.m, scripts/plot/cla.m, scripts/plot/clabel.m,
scripts/plot/clf.m, scripts/plot/close.m, scripts/plot/colorbar.m,
scripts/plot/daspect.m, scripts/plot/ezmesh.m, scripts/plot/ezmeshc.m,
scripts/plot/ezsurf.m, scripts/plot/ezsurfc.m, scripts/plot/findall.m,
scripts/plot/findobj.m, scripts/plot/gcbo.m, scripts/plot/gcf.m,
scripts/plot/gco.m, scripts/plot/grid.m, scripts/plot/guihandles.m,
scripts/plot/hdl2struct.m, scripts/plot/hidden.m, scripts/plot/hold.m,
scripts/plot/isonormals.m, scripts/plot/isosurface.m, scripts/plot/legend.m,
scripts/plot/mesh.m, scripts/plot/meshc.m, scripts/plot/meshz.m,
scripts/plot/newplot.m, scripts/plot/orient.m, scripts/plot/pareto.m,
scripts/plot/patch.m, scripts/plot/pbaspect.m, scripts/plot/pcolor.m,
scripts/plot/plot.m, scripts/plot/print.m,
scripts/plot/private/__add_default_menu__.m, scripts/plot/quiver.m,
scripts/plot/quiver3.m, scripts/plot/refreshdata.m, scripts/plot/saveas.m,
scripts/plot/scatter.m, scripts/plot/scatter3.m, scripts/plot/shading.m,
scripts/plot/shrinkfaces.m, scripts/plot/slice.m, scripts/plot/stem.m,
scripts/plot/stem3.m, scripts/plot/struct2hdl.m, scripts/plot/subplot.m,
scripts/plot/surf.m, scripts/plot/surfc.m, scripts/plot/surfl.m,
scripts/plot/tetramesh.m, scripts/plot/uigetfile.m, scripts/plot/uimenu.m,
scripts/plot/uiputfile.m, scripts/plot/waterfall.m, scripts/plot/whitebg.m,
scripts/plot/xlim.m, scripts/plot/ylim.m, scripts/plot/zlim.m,
scripts/polynomial/conv.m, scripts/polynomial/polyout.m,
scripts/polynomial/splinefit.m, scripts/set/ismember.m, scripts/set/powerset.m,
scripts/set/setdiff.m, scripts/set/union.m, scripts/set/unique.m,
scripts/signal/detrend.m, scripts/signal/filter2.m, scripts/signal/freqz.m,
scripts/signal/periodogram.m, scripts/signal/spectral_adf.m,
scripts/signal/spectral_xdf.m, scripts/sparse/eigs.m, scripts/sparse/svds.m,
scripts/specfun/legendre.m, scripts/special-matrix/gallery.m,
scripts/statistics/base/mean.m, scripts/statistics/base/moment.m,
scripts/statistics/tests/cor_test.m,
scripts/statistics/tests/kolmogorov_smirnov_test.m,
scripts/statistics/tests/kolmogorov_smirnov_test_2.m,
scripts/statistics/tests/kruskal_wallis_test.m,
scripts/statistics/tests/prop_test_2.m, scripts/statistics/tests/sign_test.m,
scripts/statistics/tests/t_test.m, scripts/statistics/tests/t_test_2.m,
scripts/statistics/tests/t_test_regression.m,
scripts/statistics/tests/u_test.m, scripts/statistics/tests/var_test.m,
scripts/statistics/tests/welch_test.m,
scripts/statistics/tests/wilcoxon_test.m, scripts/statistics/tests/z_test.m,
scripts/statistics/tests/z_test_2.m, scripts/strings/base2dec.m,
scripts/strings/index.m, scripts/strings/isstrprop.m,
scripts/strings/mat2str.m, scripts/strings/regexptranslate.m,
scripts/strings/rindex.m, scripts/strings/str2num.m, scripts/strings/strcat.m,
scripts/strings/strjust.m, scripts/strings/strmatch.m,
scripts/strings/validatestring.m, scripts/testfun/demo.m,
scripts/testfun/example.m, scripts/testfun/test.m, scripts/time/addtodate.m,
scripts/time/asctime.m, scripts/time/datestr.m, scripts/time/datetick.m,
scripts/time/weekday.m, scripts/ui/errordlg.m, scripts/ui/helpdlg.m,
scripts/ui/inputdlg.m, scripts/ui/listdlg.m, scripts/ui/msgbox.m,
scripts/ui/questdlg.m, scripts/ui/warndlg.m: Use new @qcode macro.
author | Rik <rik@octave.org> |
---|---|
date | Mon, 19 Aug 2013 20:46:38 -0700 |
parents | e39f00a32dc7 |
children | 09543e9c8f40 |
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## Copyright (C) 1994-2012 John W. Eaton ## Copyright (C) 2012 Carnë Draug ## Copyright (C) 2013 Adam H Aitkenhead ## ## This file is part of Octave. ## ## Octave 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. ## ## Octave 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 Octave; see the file COPYING. If not, see ## <http://www.gnu.org/licenses/>. ## -*- texinfo -*- ## @deftypefn {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{rgb}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{rgb}, @var{map}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{rgb}, @var{n}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{rgb}, @var{tol}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{rgb}, @var{map}, @var{dither_option}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{rgb}, @var{n}, @var{dither_option}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{rgb}, @var{tol}, @var{dither_option}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{R}, @var{G}, @var{B}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{R}, @var{G}, @var{B}, @var{map}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{R}, @var{G}, @var{B}, @var{n}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{R}, @var{G}, @var{B}, @var{tol}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{R}, @var{G}, @var{B}, @var{map}, @var{dither_option}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{R}, @var{G}, @var{B}, @var{n}, @var{dither_option}) ## @deftypefnx {Function File} {[@var{x}, @var{map}] =} rgb2ind (@var{R}, @var{G}, @var{B}, @var{tol}, @var{dither_option}) ## Convert an image in red-green-blue (RGB) color space to an indexed image. ## ## The input image @var{rgb} must be an N-dimensional RGB image ## (@nospell{MxNxO}@dots{}x3 array) where M,N,O@dots{} are the image ## dimensions, and the ## final dimension contains the values in the red, green and blue ## channels. Alternatively, the red, green and blue color channels can ## be input as separate arrays @var{R}, @var{G} and @var{B}. ## ## The input @var{map} defines the colormap to be used. Alternatively, ## @var{n} or @var{tol} may be used to define the maximum number of ## colors to use in an automatically generated colormap. @var{n} is ## related to @var{tol} by: @var{n} = (floor (1/@var{tol}) + 1)^3; ## @var{tol} must be >0 and @leq{}1. ## ## @var{dither_option} is a string which enables or disables dithering: ## @qcode{"dither"} (default) or @qcode{"nodither"}. ## ## @seealso{ind2rgb, rgb2hsv, rgb2ntsc} ## @end deftypefn ## Author: Tony Richardson <arichard@stark.cc.oh.us> ## Created: July 1994 ## Adapted-By: jwe function [x, map] = rgb2ind (varargin) ## Gather the inputs if (nargin < 1 || nargin > 6) print_usage (); else ## Test for dither_option, by checking if the final input is a string if (ischar (varargin{end})) dither_option = varargin{end}; dither_check = true; else dither_option = "dither"; dither_check = false; endif ## Read the rgb input if (nargin-dither_check==1 || nargin-dither_check==2) rgb = varargin{1}; if (size (rgb)(end) != 3) error ("rgb2ind: The input image must be an RGB image (MxNxO...x3 array)."); elseif (min (rgb(:)) < 0 || max (rgb(:)) > 1) error ("rgb2ind: The input image must contain values between 0 and 1."); endif if (nargin-dither_check==2) option = varargin{2}; else dither_option = "nodither"; endif ## Read the R,G,B inputs elseif (nargin - dither_check==3 || nargin - dither_check==4) R = varargin{1}; G = varargin{2}; B = varargin{3}; if (! size_equal (R, G, B)) error ("rgb2ind: R, G, and B must have the same size"); endif if (nargin-dither_check==4) option = varargin{4}; else dither_option = "nodither"; endif rgb = reshape ([R(:), G(:), B(:)], [size(R), 3]); endif endif sz = size (rgb); ## Apply a limited colormap if required if (exist ("option","var")) if (size (option, 1)==1) if (option>0 && option<=1) ## option: tol tol = option; n = (floor (1/option) + 1)^3; else ## option: n n = option; endif optionstr = sprintf ("-colors %d",n); else ## option: map map = option; if (isequal (map(:,1),map(:,2)) || isequal (map(:,1),map(:,3)) || isequal (map(:,2),map(:,3))) error ("rgb2ind: The colormap cannot contain matching R,G, or B channels.") endif fnmap = tmpnam; map = reshape (map, size (map, 1), 1, 3); imwrite (map, fnmap, "tiff"); optionstr = sprintf ("-map %s", fnmap); endif ## If image is an ND array, convert it to a tiled 2D image ## before processing it with Graphicsmagick if (numel (sz) > 3) rgb = reshape (rgb, [prod(sz(1:end-2)), sz(end-1), 3]); end ## Prepare the Graphicsmagick dithering option if (strcmp (dither_option, "nodither")) ditherstr = "+dither"; elseif (strcmp (dither_option, "dither")) ditherstr = "-dither"; endif ## Perform the image processing using Graphicsmagick fna = tmpnam; fnb = tmpnam; imwrite (rgb, fna, "tiff"); gmstr = sprintf ("gm convert %s %s %s %s", fna, ditherstr, optionstr, fnb); system (gmstr); rgb = imread (fnb); endif ## Conversion of rgb image to x,map pr = prod (sz(1:end-1)); x = zeros (sz(1:end-1)); [map,~,x(:)] = unique (reshape(rgb, [pr, 3]), "rows"); ## a colormap is of class double and values between 0 and 1 switch (class (rgb)) case {"single", "double", "logical"} ## do nothing, return the same case {"uint8", "uint16"} map = double (map) / double (intmax (class (rgb))); case "int16" map = (double (im) + 32768) / 65535; otherwise error ("unsupported image class %s", im_class); endswitch ## we convert to the smallest class necessary to encode the image. Matlab ## documentation does not mention what it does when uint16 is not enough... ## When an indexed image is of integer class, there's a -1 offset to the ## colormap, hence the adjustment if (rows (map) < 256) x = uint8 (x - 1); elseif (rows (map) < 65536) x = uint16 (x - 1); else ## leave it as double endif endfunction %% FIXME: Need some functional tests or %!demo blocks %% Test input validation %!error rgb2ind () %!error rgb2ind (1,2,3,4,5,6,7)