| 摘要 |
PURPOSE:To predict density of each picture element by means of density level of a remarkable picture element and a density level of each peripheral picture element in the specific picture element area centering around the foregoing. CONSTITUTION:As for an input picture element signal, its density information is subjected to multivalue quantization by a quantizer 1. And the quantized signal is sent to the memory 2, and the density level information in the specific picture element area is stored. The predictive density levels q1-q4 of each small picture element in case the remarkable element has been divided into four depending upon the contents of the memory 2 are calculated by the arithmetic unit 3, and are stored in the memory 4. The threshold corresponding to each small picture element is called from ROM5 which has stored a daze pattern, and is compared with the levels q1-q4 by the comparator 6. As a result of the foregoing, a black or white level of each small picture element is decided and a binary picture element signal whose picture element has been made to have high density is output. |
