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import math
BIT_DEPTH = 12
DCI_GAMMA = 2.6
SRGB_GAMMA = 2.4;
BIT_LENGTH = int(math.pow(2, BIT_DEPTH))
COLOR_DEPTH = BIT_LENGTH - 1
def boilerplate(f):
print >>f, """/*
Copyright (C) 2012 Carl Hetherington <cth@carlh.net>
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, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* This file is auto-generated by the build scripts; edits will be lost
on ./waf configure.
*/
"""
def make_luts():
cc = open('src/lut.cc', 'w')
boilerplate(cc)
print >>cc,"#include \"lut.h\""
print >>cc, """
/* sRGB color matrix for XYZ -> RGB */
float color_matrix[3][3] = {
{ 3.240454836, -1.537138850, -0.498531547},
{-0.969266390, 1.876010929, 0.041556082},
{ 0.055643420, -0.204025854, 1.057225162}
};\n\n
"""
print >>cc, """
float lut_in[COLOR_DEPTH + 1] = {\n
\t/* Bit depth: %d
\t * Reference white: DCI
\t * Gamma: %f
\t */
""" % (BIT_DEPTH, DCI_GAMMA)
c = 0
for i in range(0, BIT_LENGTH):
v = math.pow (i / (BIT_LENGTH - 1.0), DCI_GAMMA);
if (c == 0):
print >> cc," ",
if i < BIT_LENGTH - 1:
print >> cc,"%06f, " % v,
if c == 12:
c = 0;
print >> cc,""
else:
c += 1
else:
print >> cc,"%06f" % v
print >>cc,"};"
print >>cc, """
int lut_out[COLOR_DEPTH + 1] = {
\t/* Bit depth: %d
\t * Reference white: sRGB
\t * Gamma: %f
\t */
"""
c = 0
for i in range (0, BIT_LENGTH):
v = i / (BIT_LENGTH - 1.0)
if (v < (0.04045 / 12.92)):
v *= 12.92
else:
v = (1.055 * pow (v, (1 / SRGB_GAMMA))) - 0.055;
v *= 255
if c == 0:
print >> cc," ",
if i < BIT_LENGTH - 1:
print >> cc, "%d, " % v,
if c == 12:
c = 0;
print >> cc,""
else:
c += 1
else:
print >> cc,"%d" % v
print >>cc,"};"
h = open('src/lut.h', 'w')
boilerplate(h)
print >> h,"""
#define COLOR_DEPTH (%d)
#define DCI_COEFFICIENT (48.0/52.37)
extern float color_matrix[3][3];
extern int lut_out[COLOR_DEPTH + 1];
extern float lut_in[COLOR_DEPTH + 1];
""" % COLOR_DEPTH
if __name__ == "__main__":
make_luts()
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