My Format Factory
My Format Factory


FLI is an animation file format that falls in the ‘FLIC’ file category. FLIC is an animation format that was originally developed by Autodesk, Inc. for use with Autodesk Animator (FLI) and Autodesk Animator Pro (FLC).

The FLI file format (with the extension of ‘.fli’) has a maximum display resolution of 320 x 200 pixels, and is capable of supporting up to 64 colors. The maximum number of frames (sequences of still images) it can support is 4000, with each frame containing 8 bit of image data. This makes it the ideal file format for storing animation sequences found in graphics applications, CAD systems, and computer games.

The design of an FLI file is quite simple. It consists of a 128-byte header and then is followed by a sequence of frames. A byte-wise run-length compression scheme is used to compress the first frame. Subsequent frames are compressed using an inter-frame delta encoding scheme. This encodes only the differences between the adjacent images without encoding the frames themselves. At the end of the FLI file, there is one extra frame. This extra frame contains the difference between the first frame and the last frame. This approach results in significantly smaller files than if each frame was independently encoded.

The compression used in FLI files is lossless, which means that the file is reduced without losing the original quality. FLI files also do not require special hardware to encode or decode its data. This along with the simplicity of design and the quick playback makes FLI a very popular animation format in the MS-DOS and Windows environments.

FLI video files can be opened on Windows (using Apple QuickTime Player, Waaplay, and PowerFlic), Mac OS (using Apple QuickTime Player), and Linux (using XAnim).