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	references since December 16, 2000

Img1.2.4

This is the most stable Img release available. Except for the internationalization there are no new features, only some fixes for recently discovered bugs. Therefore everyone is recommended to upgrade.

Changes compared to version 1.2.3 (see changes file for more details)

• Bug-fix: some platforms need the "-rpath" flag in order to let libpng locate the libz library correctly. This was missing from the Makefile. Reported by Larry Virden.
• Bug-fix: XBM module could cause the application to hang with certain input or write an incomplete colormap. Reported by Gianandrea Rigoni.
• Bug-fix: BMP module sometimes wrote an incomplete color-map when the image had more than 256 colors. Reported by higuchi@cov.tytlabs.co.jp
• Bug-fix: Postscript reading can now handle postscript files bigger than the default page size. Report and fix suggestion by Carlos Vidal.
• Upgrade to libtiff 3.5.5
• Upgrade to libpng 1.0.8
• Completely rewrote installer, using Martijn Laan's Inno Setup extensions. It now looks a lot more like other modern installers for Windows 98 and Windows 2000.
• libpng on Windows is now compiled with MMX support. This makes png.dll somewhat larger, but it could result in a factor 5 speed improvement in some cases.
• Internationalization for demos and tests. Thanks to Laurent Duperval, Andreas Kupries, Juan Carlos Gil Montoro, Georgos Petatis, Keiichi Takahashi for providing the translations. If you are interested to get your own favorite language included, feel free to mail any other translations to me.
• Made PNG handler independant of stdio and jpmbuf availability in libpng. So, if your libpng is compiled with -DPNG_NO_STDIO or -DPNG_SETJMP_NOT_SUPPORTED, everything will still work now.
• Removed the patches for Tk8.0 up to 8.2 from the distribution. Anyone who is able to install them is also able to upgrade to Tk 8.3.2, which is a much better idea anyway.

New features in Img 1.2 and earlier were:

• All dll's in the Windows binary distribution (including img1280.dll) are now compiled using gcc-2.95.2.
• Fully stub-enabled, compatible with Tcl/Tk 8.0.6 (not released yet) up to 8.4. However, if you configure with "--disable-stubs", you can still use Img 1.2 with lower Tcl/Tk versions as well (with Tcl/Tk 8.0 as the absolute minimum).
• Made it more clear in the documentation that Img 1.2 doesn't use LZW-compression in any form.
• Modified BMP generation to generate 8-bit paletted if there are less than 257 colors but more than 512 pixels. Donated by Roger E Critchlow Jr
• Disabled the lzw compression option in libtiff.
• Fully functional "Makefile.gnu". You need the latest gcc-2.95 (preferable 2.95.2) and you need to create libtclstub8.2.a and libtkstub8.2.a manually.

Currently there is one source distributions, and two binary distributions:

img1.2.4.tar.gz	(for Unix)	(for Unix)	(1.6 MByte)
img-1.2.3-1.i386.rpm	(Binary for Linux-libc6)	(127 kByte)
img124.exe	(Binary for Windows 95/98/ME/NT/2000/XP/XP)	(Binary for Windows 95/98/ME/NT/2000/XP)	(800 kByte)
tcl823plus.exe	(Binary of Tcl/Tk 8.2.3plus for Windows 95/98/ME/NT/2000/XP, with the plus-, dash- and Img-patch already applied. img124.exe is not included with this installer.)	(2.2 MByte)

Img version 1.1.4 (no longer supported)

The "Img" package adds a lot of image formats to Tcl/Tk. It works in combination with the following versions:

Tcl/Tk	(version 7.5/4.1(p3), 7.6/4.2(p2), 8.0(.5) or 8.1(.1)),
Itcl	(version 2.1 or higher)
Tcl/Tk	Netscape plugin (1.1 or higher)

Currently there is a source distribution:

img1.1.4.tar.gz

(for Unix)

(1513917 bytes)

and the following binary distribution:

img114.exe (Windows 95/NT, self-extracting executable)

(849648 bytes)

introduction

This package enhances Tk, adding support for many other Image formats: BMP, XBM, XPM, GIF (with transparency, but without LZW), PNG, JPEG, TIFF and postscript. The main library is libimg1.2.so (libimg1.2.sl, libimg1.2.a, img12.dll), which handles the BMP, XBM, XPM, GIF formats and the Pixmap image type. This library can be loaded dynamically into Tcl/Tk. If these formats are all you need, no other libraries need to be installed.

If you want to write images to disk which contain transparency information (e.g. GIF89 or PNG with alpha channel), you need Tk 8.3 or higher.

In stead of LZW the run-length encoding of Hutchison Avenue Software Corporation is used, also known as miGIF compression. The miGIF compression routines do not, strictly speaking, generate files conforming to the GIF spec, since the image data is not LZW-compressed (this is the point: in order to avoid transgression of the Unisys patent on the LZW algorithm.) However, miGIF generates data streams that any reasonably sane LZW decompresser will decompress to what we want.

For PNG, JPEG and TIFF support, other dynamic libraries need to be present at runtime. These are all public domain, and no modifications are needed. If your system already has these libraries (maybe under a different name) you probably don't have to re-build them. But otherwise, the Img package contains everyting to upgrade, if you like:

Especially libpng and libjpeg are advised to be upgraded if you have an earlier version. PNG wouldn't even work with 0.90 or earlier. JPEG works, but you can expect problems with smoothing.

Many thanks to the following people:

Roger E Critchlow Jr <rec@elf.org>

BMP improvements.

Andreas Kupries <a.kupries@westend.com>

Testing on Linux, and supplying everything for the Windows port.

Nick Ing-Simmons <nick@ni-s.u-net.com>

XBM write function, perl-Tk port and many other useful suggestions.

Tom Lane <tgl@sss.pgh.pa.us>

Wrote the JPEG handler (but I'm responsible for the dynamical loading part).

Lolo <lolo@pcsig22.etsimo.uniovi.es>

Original GIF87 write function.

Ioi K. Lam <ioi@eng.sun.com>

Pixmap image type (imgPmap.c, imgUnixPmap.c, imgWinPmap.c), many functions of which are used in imgXPM.c as well.

Mario Weilguni <mweilguni@sime.com>

Many improvements to imgXPM.c.

Larry Virden <lvirden@cas.org>

Bug reports and other useful remarks.

Chris Ausbrooks <weed@bucket.pp.ualr.edu>

Created the rpm for Linux (libc6)

Enjoy,

Jan Nijtmans
LogicaCMG Arnhem B.V.

email:

jan.nijtmans@gmail.com (private)

jan.nijtmans@logicacmg.com (work)

url:

http://purl.oclc.org/net/nijtmans/