No way to decode an animated image without explicitly dispatching to a specific format decoder

[Shnatsel]

There's ImageReader::decode() for decoding a still image without worrying about which format the image has. There doesn't seem to be an equivalent of that for decoding animations.

There is the AnimationDecoder trait, but there is no method that would return impl AnimationDecoder or that would just return an iterator over frames. Not that I could find anyway.