| 摘要 |
PURPOSE:To instantaneously obtain the frequency of occurrence of each density value of an optional area, by reading out in parallel a density value collecting area setting memory equipped with areas corresponding to the unit memory areas of a picture memory and the picture memory. CONSTITUTION:When a picture memory 2 is continuously scanned, picture patterns are always displayed in a display section 3 in accordance with density values written in the picture memory 2. When a command to collect the frequency of occurrence of each density value is given to a control section 1, a collection instructing signal line L4 is turned on and a density value extracting section 6 discriminates the density value of each dot outputted from a density value outputting line L3 by means of an ON signal from a density value collecting area setting memory 4 and brings up the count value of a prescribed count area of an occurring frequency counter 5 by density value. When this operation is performed on the whole area of the memory 2, the control section 1 reads out the occurring number of times by density value preserved in the counter 5 through a line L1. |
