Add a separate header file for the D65 white point.

[movit] / d65.h

diff --git a/d65.h b/d65.h
new file mode 100644 (file)
index 0000000..86f423b
--- /dev/null
+++ b/d65.h
@@ -0,0 +1,13 @@
+#ifndef _D65_H
+#define _D65_H 1
+
+// The D65 illuminant, which is the standard white point (ie. what you should get
+// for R=G=B=1) for almost all video color spaces in common use. It has a color
+// temperature roughly around 6500 K, which is sort of bluish; it is intended to
+// simulate average daylight conditions.
+//
+// The definition (in xyz space) is given, for instance, in both Rec. 601 and 709.
+static const double d65_x = 0.3127, d65_y = 0.3290, d65_z = 1.0 - d65_x - d65_y;
+
+#endif  // !defined(_D65_H)
+