Imported from libpng-1.2.0beta5.tar
diff --git a/libpng.txt b/libpng.txt
index 0b80568..0e27c17 100644
--- a/libpng.txt
+++ b/libpng.txt
@@ -1,6 +1,6 @@
libpng.txt - A description on how to use and modify libpng
- libpng version 1.2.0beta4 - June 23, 2001
+ libpng version 1.2.0beta5 - August 8, 2001
Updated and distributed by Glenn Randers-Pehrson
<randeg@alum.rpi.edu>
Copyright (c) 1998-2001 Glenn Randers-Pehrson
@@ -78,7 +78,9 @@
instances of the structures. Each thread should have its own
png_struct and png_info instances, and thus its own image.
Libpng does not protect itself against two threads using the
-same instance of a structure.
+same instance of a structure. Note: thread safety may be defeated
+by use of some of the MMX assembler code in pnggccrd.c, which is only
+compiled when the user defines PNG_THREAD_UNSAFE_OK.
II. Structures
@@ -790,7 +792,7 @@
convert the PNG pixel data back to the original bit depth of the image.
This call reduces the pixels back down to the original bit depth:
- png_color_16p sig_bit;
+ png_color_8p sig_bit;
if (png_get_sBIT(png_ptr, info_ptr, &sig_bit))
png_set_shift(png_ptr, sig_bit);
@@ -1002,7 +1004,13 @@
The following code will reverse this (make black be one and white be
zero):
- if (bit_depth == 1 && color_type == PNG_COLOR_GRAY)
+ if (bit_depth == 1 && color_type == PNG_COLOR_TYPE_GRAY)
+ png_set_invert_mono(png_ptr);
+
+This function can also be used to invert grayscale and gray-alpha images:
+
+ if (color_type == PNG_COLOR_TYPE_GRAY ||
+ color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_invert_mono(png_ptr);
PNG files store 16 bit pixels in network byte order (big-endian,
@@ -2818,13 +2826,13 @@
IX. Y2K Compliance in libpng
-June 23, 2001
+August 8, 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 1.2.0beta4 are Y2K compliant. It is my belief that earlier
+upward through 1.2.0beta5 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