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-rw-r--r--third_party/qcms/src/qcms_util.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/third_party/qcms/src/qcms_util.c b/third_party/qcms/src/qcms_util.c
new file mode 100644
index 0000000000..9b2d9fa744
--- /dev/null
+++ b/third_party/qcms/src/qcms_util.c
@@ -0,0 +1,69 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the Chromium LICENSE file.
+
+#include "qcmsint.h"
+
+#include <math.h>
+
+typedef struct _qcms_coords {
+ float x;
+ float y;
+} qcms_coords;
+
+typedef struct _qcms_triangle {
+ qcms_coords verticies[3];
+} qcms_triangle;
+
+#define NTSC_1953_GAMUT_SIZE 0.1582
+
+static qcms_triangle get_profile_triangle(qcms_profile *profile)
+{
+ float sumRed = s15Fixed16Number_to_float(profile->redColorant.X) +
+ s15Fixed16Number_to_float(profile->redColorant.Y) +
+ s15Fixed16Number_to_float(profile->redColorant.Z);
+ float xRed = s15Fixed16Number_to_float(profile->redColorant.X) / sumRed;
+ float yRed = s15Fixed16Number_to_float(profile->redColorant.Y) / sumRed;
+
+ float sumGreen = s15Fixed16Number_to_float(profile->greenColorant.X) +
+ s15Fixed16Number_to_float(profile->greenColorant.Y) +
+ s15Fixed16Number_to_float(profile->greenColorant.Z);
+ float xGreen = s15Fixed16Number_to_float(profile->greenColorant.X) / sumGreen;
+ float yGreen = s15Fixed16Number_to_float(profile->greenColorant.Y) / sumGreen;
+
+ float sumBlue = s15Fixed16Number_to_float(profile->blueColorant.X) +
+ s15Fixed16Number_to_float(profile->blueColorant.Y) +
+ s15Fixed16Number_to_float(profile->blueColorant.Z);
+ float xBlue = s15Fixed16Number_to_float(profile->blueColorant.X) / sumBlue;
+ float yBlue = s15Fixed16Number_to_float(profile->blueColorant.Y) / sumBlue;
+
+ qcms_triangle triangle = {{{xRed, yRed}, {xGreen, yGreen}, {xBlue, yBlue}}};
+ return triangle;
+}
+
+static float get_triangle_area(const qcms_triangle candidate)
+{
+ float xRed = candidate.verticies[0].x;
+ float yRed = candidate.verticies[0].y;
+ float xGreen = candidate.verticies[1].x;
+ float yGreen = candidate.verticies[1].y;
+ float xBlue = candidate.verticies[2].x;
+ float yBlue = candidate.verticies[2].y;
+
+ float area = fabs((xRed - xBlue) * (yGreen - yBlue) - (xGreen - xBlue) * (yRed - yBlue)) / 2;
+ return area;
+}
+
+static float get_ntsc_gamut_metric_area(const qcms_triangle candidate)
+{
+ float area = get_triangle_area(candidate);
+ return area * 100 / NTSC_1953_GAMUT_SIZE;
+}
+
+float qcms_profile_ntsc_relative_gamut_size(qcms_profile *profile)
+{
+ qcms_triangle triangle = get_profile_triangle(profile);
+ return get_ntsc_gamut_metric_area(triangle);
+}
+
+