/usr/share/octave/packages/image-2.4.1/ycbcr2rgb.m is in octave-image 2.4.1-1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 | ## Copyright (C) 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} {@var{cmap} =} ycbcr2rgb (@var{YCbCrmap})
## @deftypefnx {Function File} {@var{RGB} =} ycbcr2rgb (@var{YCbCr})
## @deftypefnx {Function File} {@dots{} =} ycbcr2rgb (@dots{}, [@var{Kb} @var{Kr}])
## @deftypefnx {Function File} {@dots{} =} ycbcr2rgb (@dots{}, @var{standard})
## Convert YCbCr color space to RGB.
##
## The conversion changes the image @var{YCbCr} or colormap @var{YCbCrmap},
## from the YCbCr (luminance, chrominance blue, and chrominance red)
## color space to RGB values. @var{YCbCr} must be of class double, single,
## uint8, or uint16.
##
## The formula used for the conversion is dependent on two constants, @var{Kb}
## and @var{Kr} which can be specified individually, or according to existing
## standards:
##
## @table @asis
## @item "601" (default)
## According to the ITU-R BT.601 (formerly CCIR 601) standard. Its values
## of @var{Kb} and @var{Kr} are 0.114 and 0.299 respectively.
## @item "709" (default)
## According to the ITU-R BT.709 standard. Its values of @var{Kb} and
## @var{Kr} are 0.0722 and 0.2116 respectively.
## @end table
##
## @seealso{hsv2rgb, ntsc2rgb, rgb2hsv, rgb2ntsc, rgb2ycbcr}
## @end deftypefn
function rgb = ycbcr2rgb (ycbcr, standard = "601")
if (nargin < 1 || nargin > 2)
print_usage ();
endif
rgb = ycbcrfunc ("ycbcr2rgb", ycbcr, standard);
endfunction
%!assert (ycbcr2rgb (rgb2ycbcr (jet (10))), jet (10), 0.00001);
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