| 摘要 |
A shading correction apparatus can execute a first method of adding and averaging, in the sub-scanning direction, shading data obtained by reading a white reference plate in the main scanning direction and in the sub-scanning direction to obtain correction data to be used for shading correction and a second method of directly using shading data obtained by reading the white reference plate in the main scanning direction as correction data for shading correction. When the white reference plate is pre-scanned by an image sensor, and the minimum value of the obtained shading data is equal to or smaller than a predetermined value, the first method is selected. When the minimum value exceeds the predetermined value, the second method is selected. <IMAGE> |
