Abstract: Digital matrices, for example digitized images, are enhanced by comparing a matrix to be enhanced with plural enhancement patterns for each position in the matrix of each element of the matrix to produce pattern codes commensurate with the matches with the enhancement patterns. The pattern codes are employed to generate plural enhancement decisions for each element of the matrix and these enhancement decisions are combined to provide a single enhancement action for each element of the matrix.

Abstract: A process for high temperature sintering of ferrous powder metallurgy compacts having a substantially uniform carbon distribution which comprises:(a) heating the ferrous powder metallurgy compact in the heating zone of a sintering furnace to a temperature of about 2,300.degree. to 2,550.degree. F. (1,260.degree. to 1,399.degree. C.),(b) introducing to the heating zone an atmosphere comprising about 2 to less than 10 volume percent hydrogen, about 0.5 to 2.0 volume percent carbon monoxide, about 0.5 to 1.0 volume percent methane and the balance nitrogen, and(c) removing the sintered product from the furnace.