I have some GIF files that are not observing transparency when I load them in .NET, via System.Drawing.Image.FromFile().
However, I have a some others that do.
When I have a look at the color palette, the ones that do work have argb(0,255,255,255) and the ones that don't work have argb(0,0,0,0).
Is it possible to change the color of this layer in the images that don't work to be argb(0,255,255,255)? I'm hoping this is going to solve my problem when loading in .NET.
Update: After 5 hours trying to work out why these particular images were not working for transparency, in my application, when others did, I eventually delivered the code and images to the test environment. And in that environment, they happened to work. Same code, same images. My conclusion is that there must be a runtime difference that prevents the transparency from working, perhaps a difference in .NET versions.