Patterns, within the context of computational imaging, can be defined as "a more or less repeatable, discernible regularity in the spatial arrangement of a type of theme of more or less recurring objects, with possibly both radiometrical and geometrical features, sometimes referred to as elements of a collection of objects."[i] The term "radiometrical features" refers to what can be called "tone." Machines discern this portion of machine "sight" by measuring how an object responds to electromagnetic radiation. A machine blasts an object with either ultraviolet, visible, or infrared light, or all three and uses the resulting radiation to recognize patterns and compare them against known patterns.