1. A bar code processing apparatus comprising: a first image reading unit configured to read an image from an object to be read by visible light; a second image reading unit configured to read a fluorescent image from the object to be read by invisible light; a first detection unit configured to detect at least part of a background image included in the object to be read from a first read image read by the first image reading unit; a registration unit configured to register feature information indicative of a feature of a detection background image detected by the first detection unit; and a second detection unit configured to enhance a contrast of a background image area corresponding to at least part of the background image included in a second read image read by the second image reading unit on the basis of the feature information registered in the registration unit, and detect a fluorescent bar code from the second read image.