| 摘要 |
PURPOSE:To attain the line density conversion or magnification/reduction conversion by providing an original picture element density analyzing means analyzing density distribution of referenced original picture element information and a threshold value selecting means selecting a threshold value corresponding to the result of analysis of the said original picture element density analyzing means. CONSTITUTION:A conversion picture element position detection circuit 1 executes the detection processing of a conversion picture element position and the corresponding position of a conversion picture element, then a referenced original picture element data is extracted and inputted to a conversion picture element density operating circuit 3 and an original picture element density analyzing circuit 4a. Then the conversion picture element density calculation circuit 3 calculates the density of conversion picture element according to the referenced original picture element data and the position data of the conversion picture element outputted from the circuit 1. Further, the original picture element density analysis circuit 4a executes the surrounding mean density calculation or the detection processing of a specific pattern and the threshold value is set based on the result. The density of the conversion picture element is binary-coded based on the threshold value. Thus, the line density conversion or magnification/reduction conversion is applied without lowering the picture quality of the conversion picture element. |
