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Bourla
10th February 2004, 18:18
I am total newbie with AviSynth but I think my question still belongs to this forum...

I am trying to read animated GIF with Avisynth, with currently no success as it seems that this format is not supported by ImageReader.

I think that ImageReader uses DevIL as image library ( http://openil.sourceforge.net/ ). As the last version of DevIL supports gif (actually reintroduces GIF support), would it be possible to recompile Avisynth with this last version of DevIL and read animated GIFs ?

Any help appreciated !


PS: for patent concerns, see my post on the General Discussion forum :
http://forum.doom9.org/showthread.php?s=&threadid=70583
BlindWanderer
10th February 2004, 18:29
Gif support could be added. The only issue for gif support (i see) is that gif's are not frame rate based, each frame has a play length timecode.
sh0dan
10th February 2004, 22:36
I added this to the Sourceforge Feature Request list. If Richard don't mind I assigned it to him.
Richard Berg
21st February 2004, 14:01
As far as I can tell (http://sourceforge.net/project/showfiles.php?group_id=4470) 1.6.6 is only available for OS X.
Bourla
21st February 2004, 15:08
From the homepage, it seems available for all platforms.
But, yes, on sourceforge, version 1.6.6 files are only available for MacOsX.

Maybe the CVS is correct...
Richard Berg
22nd February 2004, 05:03
Nevermind, I think I figured it out...
Richard Berg
22nd February 2004, 08:46
Ok, updated version is compiled in.

Good:
- I made the error messages much nicer

Bad:
- no support for animated gifs is claimed
- the gif support that is claimed is read-only
- even in read mode, gif doesn't actually work. ilCopyPixels appears to act on a completely different kind of frame buffer. I thought it might be because of the color palette, but converting my test images to 256-color PNGs worked, so who knows.

I'm not terribly impressed with this package. It's a lot nicer than when I was working with libjpeg etc. individually, but it doesn't appear well-maintained. The upside-down bug is still there, for instance; just to compile the latest version I had to fix 5 or 6 incorrect file references and #defines in the .h files. At least we have a good idea of its limitations, and easy ways to work around them: Irfanview will batch convert your gifs in no time, and FlipVertical is very fast when needed.