1. A system, comprising a computing device that includes a processor and a memory, the memory storing instructions executable by the processor, the instructions including instructions for: using image metadata to perform a first sub-classification of an image, wherein the first sub-classification is deterministic; based in part on the deterministic first sub-classification, using a combination of image data of the image and the image metadata to perform a second sub-classification, and in a third sub-classification, based in part on the second sub-classification, using the image data to make a probabilistic classification of the image according to a likely phantom type.