From 99d30c3bf9c08eb94f552695f8ac542ef6edae28 Mon Sep 17 00:00:00 2001
From: Jeff Muizelaar <jmuizelaar@mozilla.com>
Date: Fri, 12 Jun 2009 14:38:32 -0400
Subject: [PATCH] Bug 497363. qcms: Add reference to the rationale for not
 correcting alpha. r=joedrew

---
 gfx/qcms/transform.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/gfx/qcms/transform.c b/gfx/qcms/transform.c
index 9e05818044b1..6ba0ef7538c1 100644
--- a/gfx/qcms/transform.c
+++ b/gfx/qcms/transform.c
@@ -668,6 +668,12 @@ static void qcms_transform_data_gray_out_lut(qcms_transform *transform, unsigned
 	}
 }
 
+/* Alpha is not corrected.
+   A rationale for this is found in Alvy Ray's "Should Alpha Be Nonlinear If
+   RGB Is?" Tech Memo 17 (December 14, 1998).
+	See: ftp://ftp.alvyray.com/Acrobat/17_Nonln.pdf
+*/
+
 static void qcms_transform_data_graya_out_lut(qcms_transform *transform, unsigned char *src, unsigned char *dest, size_t length)
 {
 	int i;