mewin/libpng
1
0
Fork 0
mirror of https://git.code.sf.net/p/libpng/code.git synced 2025-07-10 18:04:09 +02:00
Code Issues Projects Releases Wiki Activity

[libpng17] Update CHANGES and ANNOUNCE for Write code update (John Bowler)

Browse Source
This commit is contained in:
Glenn Randers-Pehrson 2016-05-04 22:02:52 -05:00
parent cde9b583a8
commit e966fac5ac
5 changed files with 47 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
ANNOUNCE
View File

@ -1,5 +1,5 @@
Libpng 1.7.0beta80 - March 9, 2016 Libpng 1.7.0beta80 - May 5, 2016
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.
@ -1264,7 +1264,25 @@ Version 1.7.0beta79 [March 9, 2016]
(Robert C. Seacord). Various other flags in png.h made unsigned as well. (Robert C. Seacord). Various other flags in png.h made unsigned as well.
Fixed some misleading indentation (Krishnaraj Bhat). Fixed some misleading indentation (Krishnaraj Bhat).
Version 1.7.0beta80 [March 9, 2016] Version 1.7.0beta80 [May 5, 2016]
Fixed typo (missing underscore) in #define PNG_READ_16_TO_8_SUPPORTED
Bug report by (Y.Ohashik).
Write code update (John Bowler):
Implemented better defaulting of zlib settings based on image properties.
Replaced pngtest.png with one compressed with the new zlib settings.
Implemented pass-through of png_write_rows when the rows can be used
directly (a common case) optimizing the handling of previous-row
buffering.
Removed the METHODICAL filter selection method and disabled the HEURISTIC
one. The first was ridiculously slow (though useful for experiments),
and the second didn't work. Filter selection is temporarily disabled (it
defaults to the lowest numbered filter in the list; typically 'none').
New handling of compression settings (incomplete), new PNG compression level
(not yet visible in an API).
Back ported 'PNG_FAST_FILTERS' from 1.6 (in png.h).
There are minimal API changes beyond removal of the selection options.
Work is still to be done to investigate a filter selection mechanism that
is at least as good as the previous one.
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

20
CHANGES
View File

@ -5564,7 +5564,25 @@ Version 1.7.0beta79 [March 9, 2016]
(Robert C. Seacord). Various other flags in png.h made unsigned as well. (Robert C. Seacord). Various other flags in png.h made unsigned as well.
Fixed some misleading indentation (Krishnaraj Bhat). Fixed some misleading indentation (Krishnaraj Bhat).
Version 1.7.0beta80 [March 9, 2016] Version 1.7.0beta80 [May 5, 2016]
Fixed typo (missing underscore) in #define PNG_READ_16_TO_8_SUPPORTED
Bug report by (Y.Ohashik).
Write code update (John Bowler):
Implemented better defaulting of zlib settings based on image properties.
Replaced pngtest.png with one compressed with the new zlib settings.
Implemented pass-through of png_write_rows when the rows can be used
directly (a common case) optimizing the handling of previous-row
buffering.
Removed the METHODICAL filter selection method and disabled the HEURISTIC
one. The first was ridiculously slow (though useful for experiments),
and the second didn't work. Filter selection is temporarily disabled (it
defaults to the lowest numbered filter in the list; typically 'none').
New handling of compression settings (incomplete), new PNG compression level
(not yet visible in an API).
Back ported 'PNG_FAST_FILTERS' from 1.6 (in png.h).
There are minimal API changes beyond removal of the selection options.
Work is still to be done to investigate a filter selection mechanism that
is at least as good as the previous one.
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

12
png.h
View File

@ -1,7 +1,7 @@
/* png.h - header file for PNG reference library /* png.h - header file for PNG reference library
* *
* libpng version 1.7.0beta80, March 9, 2016 * libpng version 1.7.0beta80, May 5, 2016
* *
* Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson * Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@ -12,7 +12,7 @@
* Authors and maintainers: * Authors and maintainers:
* libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
* libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger * libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
* libpng versions 0.97, January 1998, through 1.7.0beta80, March 9, 2016: * libpng versions 0.97, January 1998, through 1.7.0beta80, May 5, 2016:
* Glenn Randers-Pehrson. * Glenn Randers-Pehrson.
* See also "Contributing Authors", below. * See also "Contributing Authors", below.
*/ */
@ -25,7 +25,7 @@
* *
* This code is released under the libpng license. * This code is released under the libpng license.
* *
* libpng versions 1.0.7, July 1, 2000, through 1.7.0beta80, March 9, 2016, are * libpng versions 1.0.7, July 1, 2000, through 1.7.0beta80, May 5, 2016, are
* Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are * Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
* derived from libpng-1.0.6, and are distributed according to the same * derived from libpng-1.0.6, and are distributed according to the same
* disclaimer and license as libpng-1.0.6 with the following individuals * disclaimer and license as libpng-1.0.6 with the following individuals
@ -218,7 +218,7 @@
* Y2K compliance in libpng: * Y2K compliance in libpng:
* ========================= * =========================
* *
* March 9, 2016 * May 5, 2016
* *
* Since the PNG Development group is an ad-hoc body, we can't make * Since the PNG Development group is an ad-hoc body, we can't make
* an official declaration. * an official declaration.
@ -288,7 +288,7 @@
/* Version information for png.h - this should match the version in png.c */ /* Version information for png.h - this should match the version in png.c */
#define PNG_LIBPNG_VER_STRING "1.7.0beta80" #define PNG_LIBPNG_VER_STRING "1.7.0beta80"
#define PNG_HEADER_VERSION_STRING \ #define PNG_HEADER_VERSION_STRING \
" libpng version 1.7.0beta80 - March 9, 2016\n" " libpng version 1.7.0beta80 - May 5, 2016\n"
#define PNG_LIBPNG_VER_SONUM 17 #define PNG_LIBPNG_VER_SONUM 17
#define PNG_LIBPNG_VER_DLLNUM 17 #define PNG_LIBPNG_VER_DLLNUM 17
@ -1533,7 +1533,7 @@ PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr));
#endif #endif
#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */ #define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */
/* Strip the second byte of information from a 16-bit depth file. */ /* Strip the second byte of information from a 16-bit depth file. */
PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr)); PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr));
#endif #endif

2
pngconf.h
View File

@ -1,7 +1,7 @@
/* pngconf.h - machine configurable file for libpng /* pngconf.h - machine configurable file for libpng
* *
* libpng version 1.7.0beta80, March 9, 2016 * libpng version 1.7.0beta80, May 5, 2016
* *
* Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson * Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)

2
pngwutil.c
View File

@ -3341,7 +3341,7 @@ huffman_metric(png_byte prefix, png_const_bytep data, size_t length)
* Huffman code length limit of 15, so any symbol must occupy at least * Huffman code length limit of 15, so any symbol must occupy at least
* 1/32768 of the code space. Zlib also shows some unexpected behavior with * 1/32768 of the code space. Zlib also shows some unexpected behavior with
* window size increases; data compression can decrease, leading me (JB * window size increases; data compression can decrease, leading me (JB
* 20160202) to hypothesise that the addition of extra, infrequently used, * 20160202) to hypothesize that the addition of extra, infrequently used,
* zlib length codes damages the overall compression by reducing the * zlib length codes damages the overall compression by reducing the
* efficiency of the Huffman coding. * efficiency of the Huffman coding.
* *