From: Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: fli/flc files..
Date: Thu, 27 Feb 1997 20:05:31 +0000
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References: <9702271202 DOT AA11514 AT syntegra DOT bt DOT co DOT uk>
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Nigel Taylor writes:
>The question is regarding moving within the animation, is it possible 
>in any way to move BACKWARDS through an animation?? I cant see a 
>function to do this but it doesnt seem a particularly difficult task 
>to carry out unless there is something odd about the way that a FLI 
>stores data and it is impossible to restore the "previous frame" ??

Unfortunately, this is impossible, because of the way the FLI format is
constructed. The frames in an FLI file are compressed with a crude RLE
system, both within each image and from one frame to the next, so each
frame of the file only contains information about the pixels that have
changed since the previous frame. This means that the only way to play
it in reverse is to store uncompressed copies of each frame (this would
take a _lot_ of space), or to reopen the file and play through from the
beginning to the required position...

/*
 *  Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
 *  Beauty is a French phonetic corruption of a short cloth neck ornament.
 */