Use run-time-generated LUTs for XYZ/RGB conversion.

4 files changed, 64 insertions, 36 deletions

diff --git a/src/lib/colour_matrices.cc b/src/lib/colour_matrices.cc
new file mode 100644
index 000000000..4ec43f40d
--- /dev/null
+++ b/src/lib/colour_matrices.cc
@@ -0,0 +1,37 @@
+/*
+    Taken from OpenDCP: Builds Digital Cinema Packages
+    Copyright (c) 2010-2011 Terrence Meiczinger, All Rights Reserved
+
+    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/>.
+*/
+
+#include "colour_matrices.h"
+
+/* Color Matrices */
+float color_matrix[3][3][3] = {
+    /* SRGB */
+    {{0.4124564, 0.3575761, 0.1804375},
+     {0.2126729, 0.7151522, 0.0721750},
+     {0.0193339, 0.1191920, 0.9503041}},
+
+    /* REC.709 */
+    {{0.4124564, 0.3575761, 0.1804375},
+     {0.2126729, 0.7151522, 0.0721750},
+     {0.0193339, 0.1191920, 0.9503041}},
+
+    /* DC28.30 (2006-02-24) */
+    {{0.4451698156, 0.2771344092, 0.1722826698},
+     {0.2094916779, 0.7215952542, 0.0689130679},
+     {0.0000000000, 0.0470605601, 0.9073553944}}
+};
diff --git a/src/lib/lut.h b/src/lib/colour_matrices.h
index 26888a24a..8e009299a 100644
--- a/src/lib/lut.h
+++ b/src/lib/colour_matrices.h
@@ -16,18 +16,6 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-/** @file src/lut.h
- *  @brief Look-up tables for colour conversions (from OpenDCP)
- */
-
-#define BIT_DEPTH      12 
-#define BIT_PRECISION  16 
-#define COLOR_DEPTH    (4095)
-#define DCI_LUT_SIZE   ((COLOR_DEPTH + 1) * BIT_PRECISION)
-#define DCI_GAMMA      (2.6)
-#define DCI_DEGAMMA    (1/DCI_GAMMA)
-#define DCI_COEFFICENT (48.0/52.37)
-
 enum COLOR_PROFILE_ENUM {
     CP_SRGB = 0,
     CP_REC709,
@@ -35,17 +23,4 @@ enum COLOR_PROFILE_ENUM {
     CP_MAX
 };
 
-enum LUT_IN_ENUM {
-    LI_SRGB    = 0,
-    LI_REC709,
-    LI_MAX
-};
-
-enum LUT_OUT_ENUM {
-    LO_DCI    = 0,
-    LO_MAX
-};
-
 extern float color_matrix[3][3][3];
-extern float lut_in[LI_MAX][4095+1];
-extern int lut_out[1][DCI_LUT_SIZE];
diff --git a/src/lib/dcp_video_frame.cc b/src/lib/dcp_video_frame.cc
index 2f597522c..c4234b1da 100644
--- a/src/lib/dcp_video_frame.cc
+++ b/src/lib/dcp_video_frame.cc
@@ -43,9 +43,11 @@
 #include <boost/asio.hpp>
 #include <boost/filesystem.hpp>
 #include <boost/lexical_cast.hpp>
+#include <libdcp/rec709_linearised_gamma_lut.h>
+#include <libdcp/srgb_linearised_gamma_lut.h>
+#include <libdcp/gamma_lut.h>
 #include "film.h"
 #include "dcp_video_frame.h"
-#include "lut.h"
 #include "config.h"
 #include "exceptions.h"
 #include "server.h"
@@ -53,6 +55,7 @@
 #include "scaler.h"
 #include "image.h"
 #include "log.h"
+#include "colour_matrices.h"
 
 #include "i18n.h"
 
@@ -63,6 +66,8 @@ using std::cout;
 using boost::shared_ptr;
 using libdcp::Size;
 
+#define DCI_COEFFICENT (48.0 / 52.37)
+
 /** Construct a DCP video frame.
  *  @param input Input image.
  *  @param f Index of the frame within the DCP.
@@ -151,6 +156,17 @@ DCPVideoFrame::encode_locally ()
 		double x, y, z;
 	} d;
 
+	/* In sRGB / Rec709 gamma LUT */
+	shared_ptr<libdcp::LUT<float> > lut_in;
+	if (_colour_lut == 0) {
+		lut_in = libdcp::SRGBLinearisedGammaLUT::cache.get (12, 2.4);
+	} else {
+		lut_in = libdcp::Rec709LinearisedGammaLUT::cache.get (12, 1 / 0.45);
+	}
+
+	/* Out DCI gamma LUT */
+	shared_ptr<libdcp::LUT<float> > lut_out = libdcp::GammaLUT::cache.get (16, 1 / 2.6);
+
 	/* Copy our RGB into the openjpeg container, converting to XYZ in the process */
 
 	int jn = 0;
@@ -159,9 +175,9 @@ DCPVideoFrame::encode_locally ()
 		for (int x = 0; x < _image->size().width; ++x) {
 
 			/* In gamma LUT (converting 8-bit input to 12-bit) */
-			s.r = lut_in[_colour_lut][*p++ << 4];
-			s.g = lut_in[_colour_lut][*p++ << 4];
-			s.b = lut_in[_colour_lut][*p++ << 4];
+			s.r = lut_in->lut()[*p++ << 4];
+			s.g = lut_in->lut()[*p++ << 4];
+			s.b = lut_in->lut()[*p++ << 4];
 			
 			/* RGB to XYZ Matrix */
 			d.x = ((s.r * color_matrix[_colour_lut][0][0]) +
@@ -177,14 +193,14 @@ DCPVideoFrame::encode_locally ()
 			       (s.b * color_matrix[_colour_lut][2][2]));
 			
 			/* DCI companding */
-			d.x = d.x * DCI_COEFFICENT * (DCI_LUT_SIZE - 1);
-			d.y = d.y * DCI_COEFFICENT * (DCI_LUT_SIZE - 1);
-			d.z = d.z * DCI_COEFFICENT * (DCI_LUT_SIZE - 1);
+			d.x = d.x * DCI_COEFFICENT * 65535;
+			d.y = d.y * DCI_COEFFICENT * 65535;
+			d.z = d.z * DCI_COEFFICENT * 65535;
 			
 			/* Out gamma LUT */
-			_opj_image->comps[0].data[jn] = lut_out[LO_DCI][(int) d.x];
-			_opj_image->comps[1].data[jn] = lut_out[LO_DCI][(int) d.y];
-			_opj_image->comps[2].data[jn] = lut_out[LO_DCI][(int) d.z];
+			_opj_image->comps[0].data[jn] = lut_out->lut()[(int) d.x] * 4096;
+			_opj_image->comps[1].data[jn] = lut_out->lut()[(int) d.y] * 4096;
+			_opj_image->comps[2].data[jn] = lut_out->lut()[(int) d.z] * 4096;
 
 			++jn;
 		}
diff --git a/src/lib/wscript b/src/lib/wscript
index 2f1f7d325..60fa96df6 100644
--- a/src/lib/wscript
+++ b/src/lib/wscript
@@ -8,6 +8,7 @@ sources = """
           audio_content.cc
           audio_decoder.cc
           audio_mapping.cc
+          colour_matrices.cc
           config.cc
           content.cc
           cross.cc
@@ -33,7 +34,6 @@ sources = """
           job.cc
           job_manager.cc
           log.cc
-          lut.cc
           player.cc
           playlist.cc
           ratio.cc