octave-lyh: scripts/image/ntsc2rgb.m annotate

annotate scripts/image/ntsc2rgb.m @ 15714:b1cd65881592

Clean up scripts in image directory. Use Octave coding conventions. Redo docstrings. Add %!tests. * brighten.m: Put input validation first. Use iscolormap to simplify input checking. * cmunique.m: Use faster method of validating input class. * colormap.m: Tweak docstring. Improve input validation. * contrast.m: Tweak docstring. Use cmap instead of map as variable name for clarity. * gray2ind.m: Wrap long lines. Use faster method of validating input class. Delete unreachable code for n>65536. * hsv2rgb.m: Use faster method of validating input class. * imwrite.m: Tweak FIXME notes. * ind2gray.m: Use correct caller name for ind2x. Update %!tests with new 2-input calling convention. * ind2rgb.m: Tweak docstring. Update %!tests with new 2-input calling convention. * iscolormap.m: Tweak docstring. Re-order validation tests. * ntsc2rgb.m: Use faster method of validating input class. Better input validation. Add %!tests. * private/ind2x.m: Use more descriptive variable names. * rgb2hsv.m: Tweak docstring. Use faster method of validating input class. * rgb2ind.m: Tweak docstring. Wrap long lines. * rgb2ntsc.m: Use faster method of validating input class. Improve input validation. Add %!tests. * rgbplot.m: Match variable names in docstring to those in function prototype.

author	Rik <rik@octave.org>
date	Sun, 02 Dec 2012 10:02:57 -0800
parents	806ea52af230
children	3d2357969627

rev	line source
14138 72c96de7a403 maint: update copyright notices for 2012 John W. Eaton <jwe@octave.org> parents: 11587 diff changeset	1 ## Copyright (C) 1994-2012 John W. Eaton
2313 5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	2 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	3 ## This file is part of Octave.
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	4 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	5 ## Octave is free software; you can redistribute it and/or modify it
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	6 ## under the terms of the GNU General Public License as published by
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6046 diff changeset	7 ## the Free Software Foundation; either version 3 of the License, or (at
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6046 diff changeset	8 ## your option) any later version.
2313 5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	9 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	10 ## Octave is distributed in the hope that it will be useful, but
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	13 ## General Public License for more details.
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	14 ##
5ca126254d15 [project @ 1996-07-11 21:25:22 by jwe] jwe parents: 2312 diff changeset	15 ## You should have received a copy of the GNU General Public License
7016 93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6046 diff changeset	16 ## along with Octave; see the file COPYING. If not, see
93c65f2a5668 [project @ 2007-10-12 06:40:56 by jwe] jwe parents: 6046 diff changeset	17 ## <http://www.gnu.org/licenses/>.
559 4e826edfbc56 [project @ 1994-07-25 22:18:28 by jwe] jwe parents: diff changeset	18
3381 69b167451491 [project @ 1999-12-15 20:48:10 by jwe] jwe parents: 3373 diff changeset	19 ## -- texinfo --
14260 1f911333ed3d doc: Update docstrings for functions in image/ directory Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	20 ## @deftypefn {Function File} {@var{rgb_map} =} ntsc2rgb (@var{yiq_map})
1f911333ed3d doc: Update docstrings for functions in image/ directory Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	21 ## @deftypefnx {Function File} {@var{rgb_img} =} ntsc2rgb (@var{yiq_img})
1f911333ed3d doc: Update docstrings for functions in image/ directory Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	22 ## Transform a colormap or image from luminance-chrominance (NTSC) space to
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	23 ## red-green-blue (RGB) color space.
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	24 ##
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	25 ## Implementation Note:
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	26 ## The conversion matrix is chosen to be the inverse of the
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	27 ## matrix used for rgb2ntsc such that
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	28 ##
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	29 ## @example
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	30 ## x == ntsc2rgb (rgb2ntsc (x))
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	31 ## @end example
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	32 ##
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	33 ## @sc{matlab} uses a slightly different matrix where rounding
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	34 ## means the equality above does not hold.
14260 1f911333ed3d doc: Update docstrings for functions in image/ directory Rik <octave@nomad.inbox5.com> parents: 14138 diff changeset	35 ## @seealso{rgb2ntsc, hsv2rgb, ind2rgb}
3373 36405da8e173 [project @ 1999-11-23 20:54:17 by jwe] jwe parents: 3202 diff changeset	36 ## @end deftypefn
1024 56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	37
3202 44d82b369c78 [project @ 1998-10-29 20:27:57 by jwe] jwe parents: 2847 diff changeset	38 ## Author: Tony Richardson <arichard@stark.cc.oh.us>
2312 204cc7db6f4a [project @ 1996-07-11 21:20:36 by jwe] jwe parents: 2311 diff changeset	39 ## Created: July 1994
204cc7db6f4a [project @ 1996-07-11 21:20:36 by jwe] jwe parents: 2311 diff changeset	40 ## Adapted-By: jwe
1024 56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	41
2312 204cc7db6f4a [project @ 1996-07-11 21:20:36 by jwe] jwe parents: 2311 diff changeset	42 function rgb = ntsc2rgb (yiq)
1024 56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	43
56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	44 if (nargin != 1)
6046 34f96dd5441b [project @ 2006-10-10 16:10:25 by jwe] jwe parents: 5307 diff changeset	45 print_usage ();
1024 56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	46 endif
56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	47
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	48 cls = class (yiq);
15714 b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	49 if (! any (strcmp (cls, {"uint8", "uint16", "single", "double"})))
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	50 error ("ntsc2rgb: invalid data type '%s'", cls);
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	51 endif
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	52
7375 4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	53 ## If we have an image convert it into a color map.
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	54 if (ismatrix (yiq) && ndims (yiq) == 3)
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	55 is_image = true;
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	56 sz = size (yiq);
7375 4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	57 yiq = [yiq(:,:,1)(:), yiq(:,:,2)(:), yiq(:,:,3)(:)];
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	58 ## Convert to a double image.
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	59 if (isinteger (yiq))
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	60 low = double (intmin (cls));
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	61 high = double (intmax (cls));
7375 4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	62 yiq = (double (yiq) - low) / (high - low);
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	63 endif
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	64 else
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	65 is_image = false;
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	66 endif
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	67
15714 b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	68 if (! isreal (yiq) \|\| columns (yiq) != 3 \|\| issparse (yiq))
b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	69 error ("ntsc2rgb: input must be a matrix of size Nx3 or NxMx3");
7375 4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	70 endif
11587 c792872f8942 all script files: untabify and strip trailing whitespace John W. Eaton <jwe@octave.org> parents: 11523 diff changeset	71
15714 b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	72 ## Conversion matrix constructed from 'inv (rgb2ntsc matrix)'.
b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	73 ## See programming notes in rgb2ntsc.m. Note: Matlab matrix for inverse
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	74 ## is slightly different. We prefer this matrix so that
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	75 ## x == ntsc2rgb (rgb2ntsc (x)) rather than maintaining strict compatibility
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	76 ## with Matlab.
1024 56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	77 trans = [ 1.0, 1.0, 1.0;
56520a75b5b3 [project @ 1995-01-11 20:30:04 by jwe] jwe parents: 559 diff changeset	78 0.95617, -0.27269, -1.10374;
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	79 0.62143, -0.64681, 1.70062 ];
559 4e826edfbc56 [project @ 1994-07-25 22:18:28 by jwe] jwe parents: diff changeset	80
4e826edfbc56 [project @ 1994-07-25 22:18:28 by jwe] jwe parents: diff changeset	81 rgb = yiq * trans;
4e826edfbc56 [project @ 1994-07-25 22:18:28 by jwe] jwe parents: diff changeset	82
15714 b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	83 ## FIXME: ntsc2rgb does not preserve class of image.
b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	84 ## Should it also convert back to uint8, uint16 for integer images?
7375 4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	85 ## If input was an image, convert it back into one.
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	86 if (is_image)
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	87 rgb = reshape (rgb, sz);
7375 4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	88 endif
4fbfce35012a [project @ 2008-01-15 01:04:06 by jwe] jwe parents: 7017 diff changeset	89
559 4e826edfbc56 [project @ 1994-07-25 22:18:28 by jwe] jwe parents: diff changeset	90 endfunction
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	91
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	92
15714 b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	93 %% Test pure R, G, B colors
b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	94 %!assert (ntsc2rgb ([.299 .596 .211]), [1 0 0], 1e-5)
b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	95 %!assert (ntsc2rgb ([.587 -.274 -.523]), [0 1 0], 1e-5)
b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	96 %!assert (ntsc2rgb ([.114 -.322 .312]), [0 0 1], 1e-5)
b1cd65881592 Clean up scripts in image directory. Rik <rik@octave.org> parents: 15683 diff changeset	97
15683 806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	98 %!test
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	99 %! rgb_map = rand (64, 3);
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	100 %! assert (ntsc2rgb (rgb2ntsc (rgb_map)), rgb_map, 1e-3);
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	101
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	102 %!test
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	103 %! rgb_img = rand (64, 64, 3);
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	104 %! assert (ntsc2rgb (rgb2ntsc (rgb_img)), rgb_img, 1e-3);
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	105
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	106 %% Test input validation
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	107 %!error ntsc2rgb ()
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	108 %!error ntsc2rgb (1,2)
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	109 %!error <invalid data type 'cell'> ntsc2rgb ({1})
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	110 %!error <must be a matrix of size Nx3 or NxMx3> ntsc2rgb (ones (2,2))
806ea52af230 Overhaul m-files in image directory to provide better support for images stored as integers. Rik <rik@octave.org> parents: 14260 diff changeset	111

Mercurial > hg > octave-lyh

annotate scripts/image/ntsc2rgb.m @ 15714:b1cd65881592