This is the main component that's missing from minisphere for full parity.  Well, that and ColorMatrixes, but I've yet to encounter a game that uses them.

MNG should be easy, I'd just need libmng I think.  But what of the other formats, like FLIC?  Or is it even worth supporting those...?

FLC files aren't used by any Sphere games I've ever seen. Also, the MNG support is apparently wrong or at least different from what libmng does, from what I remember reading on the forums years ago.

But the support for it is troublesome, I know maybe one animation in one game that uses it (Kefka's Revenge), and it's just not really worth it in general... unless you add gif and WebM support or something. (Which would be kickass and useful.)

WebM might be interesting if you wanted to do FF7-style FMVs or such.  Allegro has an FFMPEG-based video component from what I understand, I don't know if WebM is supported or not though.

I would rather see gif, mng, or apng than WebM.

I would hope that Sphere's MNG is correct, it uses libmng! Maybe it's an older version, and the spec changed? Either way, mng is not very well loved. gif or apng would be better.

Yeah, I wasn't really going to do WebM.   If it even supported it, adding allegro_video would probably double the size of minisphere at least.  Not really worth it for a feature that probably about 1% of users will use.

I've never heard of APNG though.  Is that like the successor to MNG or...?

It's not billed as such, but it certainly seems to be. Apparently, the way that mng holds multiple png's is a hack, and the way that apng does it isn't. But they are both pretty simple extensions of png.

Or so I've heard.

I do know that apng is considered supported, and mng is not. Almost nothing except for higher-end image editors or swiss-army-image-readers opens mng anymore. And Sphere, of course