Method and apparatus for detecting cargo in container image using container wall background removal

A method of detecting cargo in a container image, the method comprising:

• receiving a backscatter X-ray target container image captured on a target container and a phantom installed at a preset location;
• acquiring a backscatter X-ray empty target container wall image of an empty container that corresponds to the target container, the phantom, and a capturing condition of the backscatter X-ray target container image;
• correcting the backscatter X-ray empty target container wall image using image information of the phantom included in the backscatter X-ray target container image and image information of the phantom included in the backscatter X-ray empty target container wall image;
• generating a difference image, in which a wall background of the target container is removed, using the backscatter X-ray target container image and the corrected backscatter X-ray empty target container wall image;
• and
• detecting cargo included in the target container based on the difference image.

An apparatus for detecting cargo in a container image, the apparatus comprising:

• a memory storing at least one instruction;
• and
• a processor configured to execute the at least one instruction stored in the memory,
• wherein the at least one instruction, when executed by the processor, causes the processor to:
• receive a backscatter X-ray target container image captured on a target container, wherein the backscatter X-ray target container image includes backscatter signals reflected from a container wall of the target container and backscatter signals reflected from a cargo inside the container wall;
• acquire a backscatter X-ray empty target container wall image of an empty container that corresponds to the target container and a capturing condition of the backscatter X-ray target container image, wherein the backscatter X-ray empty target container wall image includes the backscatter signals reflected from the container wall of the target container without accommodating the cargo therein;
• generate a difference image by removing a wall background caused by backscatter reflection from the container wall based on the backscatter X-ray target container image and the backscatter X-ray empty target container wall image;
• and
• detect the cargo included in the target container based on the difference image,
• wherein the processor additionally receives the capturing condition including a geometric condition between the target container and an X-ray source and a geometric condition between the target container and an X-ray detector, and
• acquires, as the backscatter X-ray empty target container wall image, an empty container wall image corresponding to information about the target container and the received capturing condition among empty container wall images pre-constructed for container information and each capturing condition.