In this paper the feedback pulse coupled neural network (FPCNN) is used for the segmentation and edge detection of x-ray images generated from American Science and Engineering (AS&E) Inc. systems used for cargo and pallet search. We prove that this technique is able to isolate important parts of x-ray images. Furthermore, our results show that the FPCNN has a good ability to retrieve small density variations which is one of the main goals of x-ray inspection.