1 files changed, 36 insertions, 0 deletions
diff --git a/src/display/grayscale.h b/src/display/grayscale.h
new file mode 100644
index 0000000..9c382cd
--- /dev/null
+++ b/src/display/grayscale.h
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#ifndef SEEN_DISPLAY_GRAYSCALE_H
+#define SEEN_DISPLAY_GRAYSCALE_H
+
+/*
+ * Author:
+ *   Johan Engelen <goejendaagh@zonnet.nl>
+ *
+ * Copyright (C) 2011 Author
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+typedef unsigned int guint32;
+
+/**
+ * Provide methods to calculate grayscale values (e.g. convert rgba value to grayscale rgba value).
+ */
+namespace Grayscale {
+    guint32 process(guint32 rgba);
+    guint32 process(unsigned char r, unsigned char g, unsigned char b, unsigned char a);
+    unsigned char luminance(unsigned char r, unsigned char g, unsigned char b);
+};
+
+#endif // !SEEN_DISPLAY_GRAYSCALE_H
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :