| 摘要 |
PROBLEM TO BE SOLVED: To apply proper density correction to an image in the case that a density difference is in existence on an original face due to a curved face or the presence of a photograph. SOLUTION: A peak luminance value BP is detected on the basis of luminance distribution data DN for each line from a line sensor 31 and a valid underground density allowable to an object is set on the basis thereof. In the case that the peak luminance value BP exceeds this allowable range, a change in a density information quantity is referenced and when the density change is large, it is regarded to be a density increase detected around a joint of a book, a background setting value BS is decided without correcting the detected peak luminance value data to correct the density. Furthermore, when the density change is small, it is regarded to be a high density area such as a photographing area, the peak luminance value data are corrected, the corrected background setting value BS is set to correct the density. |
