SIP intends to do imaging tasks such as filtering, blurring, edge detection, thresholding, histogram manipulation, segmentation, mathematical morphology, color image processing, etc.
These operations are useful for problem solving in real-world applications ranging from car motion planning to automatic diagnosis of medical images.

Version 0.3.1 is shipping as of May, 2004.

http://siptoolbox.sourceforge.net/

A straightforward article with some discussion and links.

http://delphi.about.com/library/weekly/aa040604a.htm

Tom Cagill creates GIF files without using LZW.

http://www.ddj.com/documents/s=1486/ddj0110o/

A library for reading and writing gif images. The save functionality uses an uncompressed gif algorithm to avoid the Unisys LZW patent. This library is based on Eric Raymond’s giflib and implements a superset of that library’s API.

Version 4.1.2 of this library shipped in March, 2004.

http://sourceforge.net/projects/libungif/

GIF Construction Set Pro represents the state of the art in GIF animation software. It will assemble your original animations effortlessly through its Animation Wizard, squeeze them down to as close to nothing as possible with its Supercompressor; create eyecatching banners and animated transitions; manage your GIF files; add transparency to existing graphics and a lot more.

Version 2.0.44 is shipping as of February, 2004.

http://www.mindworkshop.com/alchemy/gifcon.html

A free program to deal with image formats in popular medical formats, including DICOM, SPM, PNG, and GIF.

Version 0.9.1 of (X)MedCon shipped in January, 2004.

http://xmedcon.sourceforge.net/

This program is designed to help you squeeze the maximium amount of space out of GIF files while keeping the image quality at an acceptable level. Commercial code, but a free download is available.

Version 4.0 is shipping as of December, 2003.

http://www.gold-software.com/ago.shtml

Arcsoft has a line of mobile media codecs that includes support for MIDI, JPEG, PNG, GIF, and speech.

http://www.arcsoft.com/en/wireless/corelibraries.asp

A Unisys press release explaining their beliefs regarding licensing required to use GIF technology in your products. As of this posting (8/2003) the US patents appear to have expired, but there are European and Japanese patents will not expire until some time in 2004.

http://www.unisys.com/about__unisys/lzw/

Convert your GIF files to PNG format under UNIX, Linux, or Win32.

http://www.catb.org/~esr/gif2png/

This freeware program is designed to help you reduce the size of your GIF files. There are certain optimizations that can be performed with absolutely no loss of quality, as well as some that can provide additional improvements with some loss of resolution. Best of all, Trout’s GIF Optimizer is completely free.

An anonymous reader complained They call it freeware then make you pay. To be honest, I can’t see any indication of this on the web site, other than the usual request for donations. Somebody correct me if I’m wrong!

http://chemware.co.nz/tgo.htm

Corona is an image input/output library that can read, write, and manipulate image files in just a few lines of code. It can write PNG files, and read PNG, JPEG, PCX, BMP, TGA, and GIF. Corona was designed to be easy to use, and exports a straightforward C++ API. With just a few lines of C++, you can add image loading to your application.

Corona 1.0.1 shipped in May, 2003, and added support for TGA images as well as a few more functions.

http://corona.sourceforge.net/

A GIF optimizer seeks to reduce the size of your GIF files, usually without compromising image quality. Not enough detail on this site to pass judgment, but good GIF optimizers will also let you reduce the number of colors in the palette dynamically, so you can see the effect.

Real GIF Optimizer 3.05 shipped in February of 2003. I wish I could tell you what new features are in this release, but RealMultiMedia Development is one of those companies that doesn’t bother to post release notes on their web site!

http://www.realmultimedia.net/rgo.htm

Kazuo Adachi ported both of these important packages to Windows CE and Windows CE .Net. This includes binaries for what I believe are all the currently support CPUs.

http://www.tenik.co.jp/~adachi/wince/

“Compressed Image File Formats is an appealingly compact and useful guide to some of today’s most popular file formats used for image data. For any programmer who needs to know how images are stored, this concise reference can serve as a really invaluable resource.”
Note that the source code for this book includes an independent implementation of a PNG codec, which may be one of a kind. Link to the source code on this page.

Please use
this link to purchase the book through Amazon.com. Your purchase will help support this web site.

http://www.colosseumbuilders.com/imageformats/compressedimageformats.htm

Ultra GIF Optimizer is a powerful tool for optimizing GIF images. It can makes your web page load faster,save your server bandwidth charges and disk space! This is a commercial product, but it looks like you can download it and have a trial session.

http://www.exactcom.com/products/ultragifoptimizer/

A guy named Steve Blackstock takes a shot at making this all clear to you. Gives some details on the LZW variation used in GIF files.

http://www.cis.udel.edu/%7Eamer/CISC651/lzw.and.gif.explained.html

A tutorial page discussing the various image formats currently in use on the web. Nice comparisons and a good set of links.

http://www.psychology.nottingham.ac.uk/staff/cr1/graphics.html

Yes, it is possible to create GIF images with far more than 256 colors. This page will show you exactly how that is done, or at least prove to you that it is possible. It links to a GIF library called ANGIF that purports to be able to pull this trick off.

http://phil.ipal.org/tc.html

The Wikipedia entry for GIF. A reasonable amount of background and overview information.

http://en.wikipedia.org/wiki/Gif

These pages will test the various features available for GIF89a animation. Each feature is tested as independently as possible, allowing you to identify what features your browser supports and how well. The pages isolate features to prevent combination collisions (one error causing another feature to fail). Each test is composed of an animation that tests the most basic quality of the function.

http://members.aol.com/royalef/browtest.htm

This is a copy of the original GIF specification from CompuServe. It was expanded significantly by the 1989 specification.

http://members.aol.com/royalef/gif87a.txt

Another copy.

http://members.aol.com/royalef/gif89a.txt

Royal Frazier’s All About GIF89a, a bountiful page of documentation on the file format.

http://members.aol.com/royalef/gifabout.htm

Decoding GIF files and displaying them without help isn’t particularly easy. Add animation to the task and you’re looking at a ton of work. Fortunately, this MFC-compatible set of classes on the CodeProject web site does the heavy lifting for you.

http://www.codeproject.com/bitmap/pictureex.asp

Tutorial by Rich Holowczak from Rutgers U. A set of slides that would probably be really useful if you had the lecture to go with it. Without the lecture, not so hot.

http://cimic.rutgers.edu/~holowcza/present/compress/

Some thoughts by a person only known as mcb on the GIF patent controversy.

http://www.cloanto.com/users/mcb/19950127giflzw.html

InterGIF is a freeware program for making animated GIFs. It claims to do a good job of optimization. I have feedback from one use who was quite happy with the results - a sample GIF created by GIMP was reduced from 2235 bytes to 1455. Not bad.

http://utter.chaos.org.uk/~pdh/software/intergif.htm

Arturo Campos describes the specific implementation of LZW compression used in GIF files.

http://www.arturocampos.com/ac_lzw_gif.html

This is a copy of the second GIF specification from CompuServe. It added quite a few features to the GIF format. Probably the best well known of these would be the ability to add animation to GIF files.

Reader Andrew T. says: The definitive document, what more can you ask for?

http://www.w3.org/Graphics/GIF/spec-gif89a.txt