PURPOSE: To record a semi-halftone image at low cost by providing an arithmetic processor connected with an input switching network for generating an output signal concerning each block when the average tone values of these blocks is higher than a prescribed reference value. CONSTITUTION: Tone value data 'to be classified' at an input switching network 34 are parallelly sent to an arithmetic processor 40, and the arithmetic processor is connected to an output circuit 36 of the input switching network 34. The arithmetic processor 40 is composed of the cascade type network of mutually connected digital adders. The binary output signal of an output switching network 44 is sent through an output circuit 46 to a data output storage device 48. At the output switching network 44, 16 pieces of binary output signals are generated from 15 pieces of binary output signals of the arithmetic processor. Namely, one output signal is generated concerning 16 pieces of respective recording dots corresponding to this scanning field.
METHOD AND APPARATUS FOR RECORDING SEMI HALF-TONE IMAGE