[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[freetype2] master 3d77756e7: [sfnt] Improve sRGB constants.
From: |
Werner Lemberg |
Subject: |
[freetype2] master 3d77756e7: [sfnt] Improve sRGB constants. |
Date: |
Thu, 27 Jan 2022 02:48:18 -0500 (EST) |
branch: master
commit 3d77756e73c61ab37eb020a32730cda8efab79ff
Author: Tapish Ojha <tapishojha2000@gmail.com>
Commit: Werner Lemberg <wl@gnu.org>
[sfnt] Improve sRGB constants.
* src/base/ftbitmap.c (ft_gray_for_premultiplied_srgb_bgra): Use slightly
more precise values.
Fixes #1018.
---
src/base/ftbitmap.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/src/base/ftbitmap.c b/src/base/ftbitmap.c
index 8a419c221..7825895ad 100644
--- a/src/base/ftbitmap.c
+++ b/src/base/ftbitmap.c
@@ -480,7 +480,7 @@
* A gamma of 2.2 is fair to assume. And then, we need to
* undo the premultiplication too.
*
- * https://accessibility.kde.org/hsl-adjusted.php
+ *
http://www.brucelindbloom.com/index.html?WorkingSpaceInfo.html#SideNotes
*
* We do the computation with integers only, applying a gamma of 2.0.
* We guarantee 32-bit arithmetic to avoid overflow but the resulting
@@ -488,9 +488,9 @@
*
*/
- l = ( 4732UL /* 0.0722 * 65536 */ * bgra[0] * bgra[0] +
- 46871UL /* 0.7152 * 65536 */ * bgra[1] * bgra[1] +
- 13933UL /* 0.2126 * 65536 */ * bgra[2] * bgra[2] ) >> 16;
+ l = ( 4731UL /* 0.072186 * 65536 */ * bgra[0] * bgra[0] +
+ 46868UL /* 0.715158 * 65536 */ * bgra[1] * bgra[1] +
+ 13937UL /* 0.212656 * 65536 */ * bgra[2] * bgra[2] ) >> 16;
/*
* Final transparency can be determined as follows.
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- [freetype2] master 3d77756e7: [sfnt] Improve sRGB constants.,
Werner Lemberg <=