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[libpng16] Revised example.c to illustrate use of PNG_DEFAULT_sRGB and

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PNG_GAMMA_MAC_18 as parameters for png_set_gamma().
This commit is contained in:
Glenn Randers-Pehrson 2013-06-25 19:36:15 -05:00
parent 04d4e38ac2
commit b0d97356ce
3 changed files with 14 additions and 8 deletions
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7
ANNOUNCE
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@ -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 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. 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] Version 1.6.3beta08 [June 18, 2013]
Revised libpng.3 so that "doclifter" can process it. 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 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit (subscription required; visit

5
CHANGES
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@ -4589,7 +4589,10 @@ Version 1.6.3beta07 [June 8, 2013]
Version 1.6.3beta08 [June 18, 2013] Version 1.6.3beta08 [June 18, 2013]
Revised libpng.3 so that "doclifter" can process it. 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 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit (subscription required; visit

10
example.c
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@ -2,7 +2,7 @@
#if 0 /* in case someone actually tries to compile this */ #if 0 /* in case someone actually tries to compile this */
/* example.c - an example of using libpng /* 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 1998-2013 Glenn Randers-Pehrson
* Maintained 1996, 1997 Andreas Dilger) * Maintained 1996, 1997 Andreas Dilger)
* Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) * 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 */ /* If we don't have another value */
else else
{ {
screen_gamma = 2.2; /* A good guess for a PC monitor in a dimly screen_gamma = PNG_DEFAULT_sRGB; /* A good guess for a PC monitor
lit room */ in a dimly lit room */
screen_gamma = 1.7 or 1.0; /* A good guess for Mac systems */ 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 /* 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; int intent;
if (png_get_sRGB(png_ptr, info_ptr, &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 else
{ {
double image_gamma; double image_gamma;