Thread:FixSRwiki/@comment-46261745-20200812234909/@comment-31983756-20200826013903

I'm not an graphics expert so forgive me if this explanation isn't completely accurate, but basically it's like this. You know how all colors can be rendered as some variation of Red, Green, and Blue? (RGB) Alpha, transparency, is just another dimension of variance, another channel used in an image. So when an image has an alpha channel, it can have transparency basically. Only certain formats can have transparency, like for example a .jpg can't have an alpha channel (at least not traditionally, I think there might be a newer version that allows it, I forget)

So what the script is doing is just adding data to the image that says "yes it's okay to have transparency", pretty much. Then it adds the background - which is partially transparent - so if it didn't have an alpha channel this wouldn't work. Like I said all the stuff the script does is easy to do in an image editor so it's nothing super technical. Paint might have issues though...