1. A machine for classifying peripheral pattern characteristics in two dimensional scene data, comprising in combination: means responsive to electrical signal representative of two dimensional scene data and for producing therefrom a zeroth-coefficient signal representative of a one dimensional Hadamard transform coefficient of sequency zero from data patterns along a peripheral segment of said scene data, a first-coefficient signal representative of a one dimensional Hadamard transform coefficient of sequency one from data patterns along said peripheral scene segment, and a second-coefficient signal representative of a one dimensional Hadamard transform coefficient of sequency two from data patterns along said peripheral scene segment; and a logic means connected for comparing the values of said zeroth-coefficient signal, said first-coefficient signal, and said second-coefficient signal with a plurality of signals of known value and for producing therefrom pattern classification signals representative of the data patterns in said peripheral scene segments.