Imported from libpng-1.0.9beta8.tar

This commit is contained in:
Glenn Randers-Pehrson
2001-01-12 15:13:06 -06:00
parent 76e5fd642e
commit 231e687411
59 changed files with 768 additions and 989 deletions

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libpng.txt - A description on how to use and modify libpng
libpng version 1.0.9beta7 - December 28, 2000
libpng version 1.0.9beta8 - January 12, 2001
Updated and distributed by Glenn Randers-Pehrson
<randeg@alum.rpi.edu>
Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson
@@ -2242,13 +2242,22 @@ For a more compact example of writing a PNG image, see the file example.c.
V. Modifying/Customizing libpng:
There are two issues here. The first is changing how libpng does
There are three issues here. The first is changing how libpng does
standard things like memory allocation, input/output, and error handling.
The second deals with more complicated things like adding new chunks,
adding new transformations, and generally changing how libpng works.
Both of those are compile-time issues; that is, they are generally
determined at the time the code is written, and there is rarely a need
to provide the user with a means of changing them. The third is a
run-time issue: choosing between and/or tuning one or more alternate
versions of computationally intensive routines; specifically, optimized
assembly-language (and therefore compiler- and platform-dependent)
versions.
Memory allocation, input/output, and error handling
All of the memory allocation, input/output, and error handling in libpng
goes through callbacks that are user settable. The default routines are
goes through callbacks that are user-settable. The default routines are
in pngmem.c, pngrio.c, pngwio.c, and pngerror.c, respectively. To change
these functions, call the appropriate png_set_*_fn() function.
@@ -2596,6 +2605,7 @@ When PNG_DEBUG = 1, the macros are defined, but only png_debug statements
having level = 0 will be printed. There aren't any such statements in
this version of libpng, but if you insert some they will be printed.
VI. MNG support
The MNG specification (available at http://www.libpng.org/pub/mng) allows
@@ -2672,13 +2682,13 @@ application:
VIII. Y2K Compliance in libpng
December 28, 2000
January 12, 2001
Since the PNG Development group is an ad-hoc body, we can't make
an official declaration.
This is your unofficial assurance that libpng from version 0.71 and
upward through 1.0.9beta7 are Y2K compliant. It is my belief that earlier
upward through 1.0.9beta8 are Y2K compliant. It is my belief that earlier
versions were also Y2K compliant.
Libpng only has three year fields. One is a 2-byte unsigned integer that