From 5b03469a93ba523423de25eb122ed2c1ee88a483 Mon Sep 17 00:00:00 2001 From: Glenn Randers-Pehrson Date: Wed, 13 Jul 2011 09:37:01 -0500 Subject: [PATCH] [master] Minor editing of libpng.3 and libpng-*.txt --- libpng-1.4.9beta01.txt | 27 ++++++++++++++++----------- libpng.3 | 35 ++++++++++++++++++++--------------- 2 files changed, 36 insertions(+), 26 deletions(-) diff --git a/libpng-1.4.9beta01.txt b/libpng-1.4.9beta01.txt index 16593c054..80e22ad16 100644 --- a/libpng-1.4.9beta01.txt +++ b/libpng-1.4.9beta01.txt @@ -1,6 +1,6 @@ libpng.txt - A description on how to use and modify libpng - libpng version 1.4.9beta01 - July 8, 2011 + libpng version 1.4.9beta01 - July 13, 2011 Updated and distributed by Glenn Randers-Pehrson Copyright (c) 1998-2010 Glenn Randers-Pehrson @@ -11,7 +11,7 @@ libpng.txt - A description on how to use and modify libpng Based on: - libpng versions 0.97, January 1998, through 1.4.9beta01 - July 8, 2011 + libpng versions 0.97, January 1998, through 1.4.9beta01 - July 13, 2011 Updated and distributed by Glenn Randers-Pehrson Copyright (c) 1998-2010 Glenn Randers-Pehrson @@ -696,7 +696,8 @@ pointer into the info_ptr is returned for any complex types. (PNG_VALID_tIME) png_get_bKGD(png_ptr, info_ptr, &background); - background - background color (PNG_VALID_bKGD) + background - background color (of type + png_color_16p) (PNG_VALID_bKGD) valid 16-bit red, green and blue values, regardless of color_type @@ -1182,7 +1183,6 @@ histogram, it may not do as good a job. PNG_INFO_PLTE)) { png_uint_16p histogram = NULL; - png_get_hIST(png_ptr, info_ptr, &histogram); png_set_quantize(png_ptr, palette, num_palette, @@ -1971,7 +1971,8 @@ width, height, bit_depth, and color_type must be the same in each call. (PNG_VALID_tIME) png_set_bKGD(png_ptr, info_ptr, background); - background - background color (PNG_VALID_bKGD) + background - background color (of type + png_color_16p) (PNG_VALID_bKGD) png_set_text(png_ptr, info_ptr, text_ptr, num_text); text_ptr - array of png_text holding image @@ -2633,7 +2634,8 @@ However, there are some uncertainties about the status of local variables after a longjmp, so the user may want to be careful about doing anything after setjmp returns non-zero besides returning itself. Consult your compiler documentation for more details. For an alternative approach, you -may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net). +may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net), +which is illustrated in pngvalid.c and in contrib/visupng. Custom chunks @@ -2651,8 +2653,11 @@ and look at how other chunks were designed, so you can do things similarly. Second, check out the sections of libpng that read and write chunks. Try to find a chunk that is similar to yours and use it as a template. More details can be found in the comments inside -the code. It is best to handle unknown chunks in a generic method, -via callback functions, instead of by modifying libpng functions. +the code. It is best to handle private or unknown chunks in a generic method, +via callback functions, instead of by modifying libpng functions. This +is illustrated in pngtest.c, which uses a callback function to handle a +private "vpAg" chunk and the new "sTER" chunk, which are both unknown to +libpng. If you wish to write your own transformation for the data, look through the part of the code that does the transformations, and check out some of @@ -2841,8 +2846,8 @@ capability, which you'll still have). All the reading and writing specific code are in separate files, so the linker should only grab the files it needs. However, if you want to make sure, or if you are building a stand alone library, all the -reading files start with pngr and all the writing files start with -pngw. The files that don't match either (like png.c, pngtrans.c, etc.) +reading files start with "pngr" and all the writing files start with "pngw". +The files that don't match either (like png.c, pngtrans.c, etc.) are used for both reading and writing, and always need to be included. The progressive reader is in pngpread.c @@ -3307,7 +3312,7 @@ Other rules can be inferred by inspecting the libpng source. XIII. Y2K Compliance in libpng -July 8, 2011 +July 13, 2011 Since the PNG Development group is an ad-hoc body, we can't make an official declaration. diff --git a/libpng.3 b/libpng.3 index 2049225b9..86ca62066 100644 --- a/libpng.3 +++ b/libpng.3 @@ -1,4 +1,4 @@ -.TH LIBPNG 3 "July 8, 2011" +.TH LIBPNG 3 "July 13, 2011" .SH NAME libpng \- Portable Network Graphics (PNG) Reference Library 1.4.9beta01 .SH SYNOPSIS @@ -895,7 +895,7 @@ Following is a copy of the libpng-manual.txt file that accompanies libpng. .SH LIBPNG.TXT libpng.txt - A description on how to use and modify libpng - libpng version 1.4.9beta01 - July 8, 2011 + libpng version 1.4.9beta01 - July 13, 2011 Updated and distributed by Glenn Randers-Pehrson Copyright (c) 1998-2010 Glenn Randers-Pehrson @@ -906,7 +906,7 @@ libpng.txt - A description on how to use and modify libpng Based on: - libpng versions 0.97, January 1998, through 1.4.9beta01 - July 8, 2011 + libpng versions 0.97, January 1998, through 1.4.9beta01 - July 13, 2011 Updated and distributed by Glenn Randers-Pehrson Copyright (c) 1998-2010 Glenn Randers-Pehrson @@ -1591,7 +1591,8 @@ pointer into the info_ptr is returned for any complex types. (PNG_VALID_tIME) png_get_bKGD(png_ptr, info_ptr, &background); - background - background color (PNG_VALID_bKGD) + background - background color (of type + png_color_16p) (PNG_VALID_bKGD) valid 16-bit red, green and blue values, regardless of color_type @@ -2077,7 +2078,6 @@ histogram, it may not do as good a job. PNG_INFO_PLTE)) { png_uint_16p histogram = NULL; - png_get_hIST(png_ptr, info_ptr, &histogram); png_set_quantize(png_ptr, palette, num_palette, @@ -2866,7 +2866,8 @@ width, height, bit_depth, and color_type must be the same in each call. (PNG_VALID_tIME) png_set_bKGD(png_ptr, info_ptr, background); - background - background color (PNG_VALID_bKGD) + background - background color (of type + png_color_16p) (PNG_VALID_bKGD) png_set_text(png_ptr, info_ptr, text_ptr, num_text); text_ptr - array of png_text holding image @@ -3528,7 +3529,8 @@ However, there are some uncertainties about the status of local variables after a longjmp, so the user may want to be careful about doing anything after setjmp returns non-zero besides returning itself. Consult your compiler documentation for more details. For an alternative approach, you -may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net). +may wish to use the "cexcept" facility (see http://cexcept.sourceforge.net), +which is illustrated in pngvalid.c and in contrib/visupng. .SS Custom chunks @@ -3546,8 +3548,11 @@ and look at how other chunks were designed, so you can do things similarly. Second, check out the sections of libpng that read and write chunks. Try to find a chunk that is similar to yours and use it as a template. More details can be found in the comments inside -the code. It is best to handle unknown chunks in a generic method, -via callback functions, instead of by modifying libpng functions. +the code. It is best to handle private or unknown chunks in a generic method, +via callback functions, instead of by modifying libpng functions. This +is illustrated in pngtest.c, which uses a callback function to handle a +private "vpAg" chunk and the new "sTER" chunk, which are both unknown to +libpng. If you wish to write your own transformation for the data, look through the part of the code that does the transformations, and check out some of @@ -3736,8 +3741,8 @@ capability, which you'll still have). All the reading and writing specific code are in separate files, so the linker should only grab the files it needs. However, if you want to make sure, or if you are building a stand alone library, all the -reading files start with pngr and all the writing files start with -pngw. The files that don't match either (like png.c, pngtrans.c, etc.) +reading files start with "pngr" and all the writing files start with "pngw". +The files that don't match either (like png.c, pngtrans.c, etc.) are used for both reading and writing, and always need to be included. The progressive reader is in pngpread.c @@ -4202,7 +4207,7 @@ Other rules can be inferred by inspecting the libpng source. .SH XIII. Y2K Compliance in libpng -July 8, 2011 +July 13, 2011 Since the PNG Development group is an ad-hoc body, we can't make an official declaration. @@ -4464,7 +4469,7 @@ possible without all of you. Thanks to Frank J. T. Wojcik for helping with the documentation. -Libpng version 1.4.9beta01 - July 8, 2011: +Libpng version 1.4.9beta01 - July 13, 2011: Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc. Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net). @@ -4487,7 +4492,7 @@ this sentence. This code is released under the libpng license. -libpng versions 1.2.6, August 15, 2004, through 1.4.9beta01, July 8, 2011, are +libpng versions 1.2.6, August 15, 2004, through 1.4.9beta01, July 13, 2011, are Copyright (c) 2004,2006-2007 Glenn Randers-Pehrson, and are distributed according to the same disclaimer and license as libpng-1.2.5 with the following individual added to the list of Contributing Authors @@ -4586,7 +4591,7 @@ certification mark of the Open Source Initiative. Glenn Randers-Pehrson glennrp at users.sourceforge.net -July 8, 2011 +July 13, 2011 .\" end of man page