1 files changed, 38 insertions, 0 deletions
diff --git a/src/srgb_linearised_gamma_lut.cc b/src/srgb_linearised_gamma_lut.cc
new file mode 100644
index 00000000..1c10e118
--- /dev/null
+++ b/src/srgb_linearised_gamma_lut.cc
@@ -0,0 +1,38 @@
+/*
+    Copyright (C) 2012-2013 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.
+
+*/
+
+#include "srgb_linearised_gamma_lut.h"
+
+using namespace libdcp;
+
+LUTCache<SRGBLinearisedGammaLUT> SRGBLinearisedGammaLUT::cache;
+
+SRGBLinearisedGammaLUT::SRGBLinearisedGammaLUT (int bits, float gamma)
+	: LUT<float> (bits, gamma)
+{
+	int const bit_length = pow (2, bits);
+	for (int i = 0; i < bit_length; ++i) {
+		float const p = static_cast<float> (i) / (bit_length - 1);
+		if (p > 0.04045) {
+			_lut[i] = pow ((p + 0.055) / 1.055, gamma);
+		} else {
+			_lut[i] = p / 12.92;
+		}
+	}
+}