From b0d97356ce3023d4900011f0c870365f56fd7bb5 Mon Sep 17 00:00:00 2001
From: Glenn Randers-Pehrson <glennrp at users.sourceforge.net>
Date: Tue, 25 Jun 2013 19:36:15 -0500
Subject: [PATCH] [libpng16] Revised example.c to illustrate use of
 PNG_DEFAULT_sRGB and

PNG_GAMMA_MAC_18 as parameters for png_set_gamma().
---
 ANNOUNCE  |  7 +++++--
 CHANGES   |  5 ++++-
 example.c | 10 +++++-----
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/ANNOUNCE b/ANNOUNCE
index cbd05871f..d01a06d9c 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.6.3beta09 - June 18, 2013
+Libpng 1.6.3beta09 - June 26, 2013
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -105,7 +105,10 @@ Version 1.6.3beta07 [June 8, 2013]
 Version 1.6.3beta08 [June 18, 2013]
   Revised libpng.3 so that "doclifter" can process it.
 
-Version 1.6.3beta09 [June 18, 2013]
+Version 1.6.3beta09 [June 26, 2013]
+  Revised example.c to illustrate use of PNG_DEFAULT_sRGB and PNG_GAMMA_MAC_18
+    as parameters for png_set_gamma().  These have been available since
+    libpng-1.5.4.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index a64e061ad..5bf25768e 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4589,7 +4589,10 @@ Version 1.6.3beta07 [June 8, 2013]
 Version 1.6.3beta08 [June 18, 2013]
   Revised libpng.3 so that "doclifter" can process it.
 
-Version 1.6.3beta09 [June 18, 2013]
+Version 1.6.3beta09 [June 26, 2013]
+  Revised example.c to illustrate use of PNG_DEFAULT_sRGB and PNG_GAMMA_MAC_18
+    as parameters for png_set_gamma().  These have been available since
+    libpng-1.5.4.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/example.c b/example.c
index ee4e227bc..0ab0a15db 100644
--- a/example.c
+++ b/example.c
@@ -2,7 +2,7 @@
 #if 0 /* in case someone actually tries to compile this */
 
 /* example.c - an example of using libpng
- * Last changed in libpng 1.6.0 [February 14, 2013]
+ * Last changed in libpng 1.6.3 [(PENDING RELEASE)]
  * Maintained 1998-2013 Glenn Randers-Pehrson
  * Maintained 1996, 1997 Andreas Dilger)
  * Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -441,9 +441,9 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    /* If we don't have another value */
    else
    {
-      screen_gamma = 2.2;  /* A good guess for a PC monitor in a dimly
-                              lit room */
-      screen_gamma = 1.7 or 1.0;  /* A good guess for Mac systems */
+      screen_gamma = PNG_DEFAULT_sRGB;  /* A good guess for a PC monitor
+                              in a dimly lit room */
+      screen_gamma = PNG_GAMMA_MAC_18 or 1.0; /* Good guesses for Mac systems */
    }
 
    /* Tell libpng to handle the gamma conversion for you.  The final call
@@ -455,7 +455,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    int intent;
 
    if (png_get_sRGB(png_ptr, info_ptr, &intent))
-      png_set_gamma(png_ptr, screen_gamma, 0.45455);
+      png_set_gamma(png_ptr, screen_gamma, PNG_DEFAULT_sRGB);
    else
    {
       double image_gamma;