| 摘要 |
PURPOSE:To obtain a signal level average in an area at low cost with a simple constitution irrespective of the size of a moving average area by dividing a signal level value operated by an addition means by the number of the picture elements of the moving average area by a moving average arithmetic means. CONSTITUTION:The moving average area of an object picture is scanned by a detecting head 10 to detect the signal level for every picture element and input to a shift register group 21. This register group 21 is constituted correspondingly to the picture elements of the number (m) of rows and the number (n) of a columns, a signal detected by the head 10 is added to a signal obtained by subtracting a detecting signal before the (m) rows from the output of a subtracter 23 by an adder 22 and the output is stored in a shift register 24. The latest (m) rows for every picture element stored in this register 24 is divided by the number (m) of the rows in the area by a divider 25. The signal of the (n) columns is processed by a subtracter 28, a shift register 26, an adder 27 and a divider 30 or the like and the average value of the signal level in the area 2 is calculated with a simple constitution. |
