FLI2GIF

Well folks, this is the second release of a graphics utility that should be useful to nearly anyone wanting to develop nifty looking world wide web pages.

This little program will take an Autodesk Flic (FLI/FLC) file and convert all of its frames into sequential images in a GIF89a file, along with a Netscape application extension animation chunk. This allows you to easily create animated GIF's that are viewable by Netscape Navigator 2 and Microsoft Internet Explorer 3 (and above) users.

This capability is especially useful because there currently exist no easy to use animated GIF creation programs. Typically, if you want to create such an animation, you must use create multiple single-image files and use one of the various utilities available to combine them.

By using my program, you can use any animation program that can output Autodesk Flic files. This includes Autodesk Animator, Autodesk Animator Pro, Autodesk 3D-Studio, and many others. Additionally, there exist utilities to convert from nearly any other animation format into the flic format, allowing even more possibilities of animation conversion without having to resort to saving out individual frames to separate files.

This package should include a 16-bit DOS version of the program, in addition to a 32-bit Win32 command-line version. The Win32 version will run under Windows 95 or Windows NT at a command prompt and is better than the 16-bit DOS version because it is not limited to only using convention memory (below 640k).

Additionally, the included source code has been successfully compiled under the GNU C++ compiler. This means that you should be able to recompile this utility under most UNIX environments without any problems.

Just run FLI2GIF with the filename of your flic file and the filename of your desired GIF file.

By default, FLI2GIF will assume that color 0 is the background color used in the animation and will try to crop each frame to the smallest region possible. The background color will also be made transparent in the final GIF. If you do not want the background color made transparent, specify the "/T" option.

If you used a background color other than 0, you can use the "/B" option to specify the appropriate color. An example of using this command line option would be "FLI2GIF myflic.flc mygif.gif /B42"

If FLI2GIF detects that it is unable to crop the animation any smaller, your animation may already be optimally cropped, or you may have used a background color other than 0. In such a case, it will try to suggest the color that dominates two of the edges of your animation and display its number. You can specify this color using the /B option.

You can also have FLI2GIF interlace the images in your flic with the /I option. This is typically not very useful in animated gifs, though it can produce some interesting effects.

Specifying the /C option will tell FLI2GIF to do a "best crop" for each frame. Without this option, all frames will be cropped to the smallest common rectangle and translational offsets will be used to properly compensate for the different frame sizes. Using this option will produce slightly smaller GIFs, but be warned that not all programs correctly interpret the translational offsets and will cause your frames to 'jump' in position occasionally. Microsoft Internet Explorer 3.0 is one of the programs that ignores the offsets.

The Autodesk .FLC format allows for animations with varying color depths. Unfortunately, I have only added support for 256 color animations. If you have an animation with a different color depth, you will have to process it so that it contains only 256 colors. A good MS-DOS command line utility that can do this is VFD 1.6g (Video for DOS). You can download that handy program from various places on the Internet, including the "animate" directory on the Simtel.net archive. Just one of the many URLs from which it can be downloaded from is http://www.cdrom.com/pub/simtelnet/msdos/animate/vfd16g.zip

For more information on the Autodesk Flic format, please visit the URL http://crusty.er.usgs.gov/flc.html

The source code is provided in order to allow others to possibly add additional functionality or resolve some of its current limitations (256 color requirement, flic only support, conventional memory requirement, etc). However, I do request that if you make any changes to it that you at least send me a copy of your changes so that I can continue to distribute the latest version to those who need to download it.

All of the source code was designed to be compiled with Borland C++ 4.52, though it is possible that it may work under compilers by different vendors. Similary, if you make changes that allow it to compile under different compilers, send me a copy of the source.

I've been recently able to get the source to compile under a version of GNU C++ on one of the UNIX machines that I happened to try it on, though I haven't done very extensive testing of things under it. Much effort was made to try to make the source non-dependent upon the byte ordering used by the target platform, so I don't expect any major problems. Note that UNIX machines typically expect C++ programs to have an extension of .cc or .cxx, while all of my files are named .cpp to match the DOS standard. You'll either have to rename them before trying a UNIX compile, or force your compiler to do a C++ compile on my code.

The flic and gif handling code source was based on freely available code and documentation, though everything you see in this archive has been throughly rehacked a bit by me.

This program and its source code is distributed under the terms of a BSD-style license. Please see the separate LICENSE file for specifics.

Note that all registered trademarks mentioned in this document are property of their respective owners.

• Initial release.

• Changes to source made to allow successful compilation under GNU C++, Borland C++ (Win32), and Microsoft Visual C++.
• Added support to flic routines to skip Animator Pro prefix chunks that may be found in animations. Unknown if necessary.
• BestCrop is now disabled by default, but can be enabled with the new /C option.
• Now only requires one filename to be specified on the command-line (a target name will be made up). Allows easy drag and drop from Win95.
• Resolved a major bug that would most definitely cause the compression code to lock up on complicated images (ie: when the hash table needed to be cleared).
• The FLI2GIF.EXE executable included in the distribution archive is now a dual-mode program. When it is run at a plain DOS prompt, the standard 16-bit DOS version will execute. When it is run inside of a Win95 or WinNT command prompt, a Win32 version will execute. The Win32 version does not have the conventional memory limitation that the 16-bit version has, thus allowing you to convert flics as large as you like.

I can reached through E-mail at:

    jeff@bovine.net

The latest version of this program should always be available from my home page at https://github.com/bovine/fli2gif/