Digital image processing apparatus with interpolation and adder circuits

摘要

Input data is sampled discretely by a sampling circuit and a cumulative histogram of a plurality of bars is prepared by a cumulative histogram preparing circuit on the basis of the sampled input data. The cumulative histogram is latched by a latch circuit for three vertical scanning periods. Bar values of the cumulative histogram are used by an interpolation circuit to perform contrast conversion of the input data. A gamma circuit applies the gamma characteristic to the data subject to the contrast conversion. An output of the gamma circuit and the input data are inputted to an adder circuit so as to be added and averaged at a predetermined ratio.