Threat detection and discrimination using computer vision and magnetic spectrum observation

A system comprising:

• a magnetic field transmitter configured to generate a first magnetic field including a first frequency component, and a second frequency component;
• a plurality of magnetic field receivers including magnetic sensors, the plurality of magnetic field receivers configured to sample a combination of the first magnetic field and a second magnetic field resulting from interaction of the first magnetic field and an object;
• at least one image sensor;
• a memory storing non-transitory, computer-readable instructions;
• and
• at least one data processor configured to execute the instructions, which cause the at least one data processor to perform operations comprising:
• receiving, from the at least one image sensor, first data characterizing image data of a person passing through an inspection volume;
• receiving, from the plurality of magnetic field receivers, second data characterizing samples obtained by the plurality of magnetic field receivers;
• classifying the object as threat or non-threat based on the received second data and a polarizability index determined for the object characterizing a magnetic polarizability property of the object;
• determining, responsive to classifying the object as a threat, third data characterizing an indication of the object overlaid atop the first data;
• comparing the polarizability index determined for the object and the indication of the object in the third data;
• determining, based on the comparing, an alarm status associated with the object and/or the person;
• and
• providing the determined alarm status.