| 摘要 |
PURPOSE:To reduce variance in the quantity of exposure for a slight difference between image, variance in set value, etc., by determining weight for a pattern according to the degree of consistency between feature quantities of a color original image and a decision condition, and weighting exposure quantities determined from an exposure quantity arithmetic expression and determining a final exposure quantity. CONSTITUTION:A sensor 28 divides the color original image into many parts, measures light, and inputs measured values to an exposure control circuit 40. Plural feature quantities of the color original image are found from the data obtained by the light measurement, the degree of consistency is found from the decision condition which determines the degree of consistency so that the feature quantities are larger and larger as the condition of a decision value is satisfied more and more and are smaller and smaller as that is satisfied less and less, and plural degrees of consistency with the decision condition are put together to determine the degree of consistency with plural patterns. The weight for each pattern is found from the degree of consistency with the pattern, exposure quantities determined from the exposure condition or exposure quantity arithmetic expression are weighted, and the exposure quantity is determined according to the mean of weighting. A dimming filter 60 is controlled through a driver 30 according to the exposure quantity to perform printing operation. |
