@Lady I chose 'intended to be perceived visually' because that's the closest to my reasoning. But my exact reasoning is more like 'labelling it as video seems inaccurate, because it has no audio capability, and it seems excessive to come up with an entirely new category like 'animated image' just to accomodate the idea of an image format with no audio channel (especially since it's just this one format that constitutes most if not all of this category of file formats on the web).