gif images are always encoded as GIF89a

[Machine Learning and Applications Group]

I'm not sure if this is a bug. Is there a reason for that?

[Vincent Berthoux]

It's simpler and valid to target the 89a version, enabling to share the same code for single images and animations. Writing a "Graphic Control Extension" mandate the use of this version, and as the block is optional, using this version is always valid.

[Machine Learning and Applications Group]

Uhm, i see. In any case, some utilities from giflib as well as others like gif2tiff expect always a GIF87a.

[Vincent Berthoux]

I can still add a check for single image file, to put a 87a version

[Machine Learning and Applications Group]

Sure!, it will be nice to add another option for testing. Let me know if you need something..