1. A system for determining container code comprising: at least one camera mounted on a container handler, said container handler hoisting or lowering a container; a computer system that is electrically coupled to said at least one camera; and electronic circuitry electrically coupled to said computer system; a motor attached to said container handler; a mobile support coupled to said motor; whereby when said cargo container is hoisted or lowered to a specific height, said computer system receives a trigger signal from said electronic circuitry to take a plurality of digital images from said at least one camera, extracts container recognition results from said plurality of digital images, and combines said results together to produce said container code, wherein said at least one camera is mounted on said mobile support so that said computer system commands said motor to move said at least one camera to a predefined position according to the length of said container being hoisted or lowered.