No not animated, I mean that the .png format specifies how to specify an arbitrary number of datablocks, without specifying how they should be used aside from

No not animated, I mean that the .png format specifies how to specify an arbitrary number of datablocks, without specifying how they should be used aside from amounts to an recommendation of which one should be shown. It used by some videogames as assets, for instance storing what amounts as a thumbnail as a shown image, but leaving meshes and textures in the other internal datablocks.