Gif format


The Gif library seems to decode only 89a version file but not the basic version 87a.
Is there a plan to integrate this version in the decoder ? Anyway, ImageTools is a very usefull library !

file attachments


malignate88 wrote May 10, 2011 at 9:31 AM

Hi, afaik my library supports old gifs, but not all formats, some
interlacing formats can cause problems yet.

There is the plan to extend it my time is limited at the moment. Can you
send me the images where you have problems with?

samoteph wrote May 10, 2011 at 9:39 AM

the image is attached with the description.

Necroman wrote Jul 9, 2012 at 10:37 AM

Gif decoding crashes on the attached file:
it's a showstopper for me - I cannot publish my WP7 app where certain images cannot be decoded. Please fix it soon if possible, thanks.

Necroman wrote Jul 9, 2012 at 10:44 AM

Edit: the file I mentioned is 161583.strip.sunday.gif
This exception is thrown when decoding the image:

at ImageTools.IO.Gif.GifDecoder.ReadFrameColors(Byte[] indices, Byte[] colorTable, GifImageDescriptor descriptor)
at ImageTools.IO.Gif.GifDecoder.ReadFrame()
at ImageTools.IO.Gif.GifDecoder.Decode(ExtendedImage image, Stream stream)

Necroman wrote Jul 9, 2012 at 11:00 AM

False alarm, Gif decoding works, the only problem was GifDecoder is NOT thread safe - I was decoding multiple images in multiple threads using one GifDecoder instance and one of these images had different dimensions and it was causing IndexOutOfRangeException. Making ImageTools encoders and decoders thread safe might be a good idea :)