1. An anatomical image correction system, including: a memory that stores truncated anatomical image data acquired during a scan of a subject and positron emission tomography (PET) data acquired during a PET scan of the subject; and a processor that reconstructs a non-attenuation-corrected (NAC) PET image from the acquired PET data, generates an attenuation map from the acquired truncated anatomical image data, and compensates for truncated image data in the attenuation map using a contour in the NAC PET image.