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/*
* DDS GIMP plugin
*
* Copyright (C) 2004-2012 Shawn Kirst <skirst@gmail.com>,
* with parts (C) 2003 Arne Reuter <homepage@arnereuter.de> where specified.
*
* 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; see the file COPYING. If not, write to
* the Free Software Foundation, 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301, USA.
*/
#include <math.h>
#include "color.h"
int
linear_to_sRGB(int c)
{
float v = (float)c / 255.0f;
if(v < 0)
v = 0;
else if(v > 1)
v = 1;
else if(v <= 0.0031308f)
v = 12.92f * v;
else
v = 1.055f * powf(v, 0.41666f) - 0.055f;
return (int)floorf(255.0f * v + 0.5f);
}
int
sRGB_to_linear(int c)
{
float v = (float)c / 255.0f;
if(v < 0)
v = 0;
else if(v > 1)
v = 1;
else if(v <= 0.04045f)
v /= 12.92f;
else
v = powf((v + 0.055f) / 1.055f, 2.4f);
return (int)floorf(255.0f * v + 0.5f);
}
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