| 摘要 |
PROBLEM TO BE SOLVED: To improve accuracy for the discrimination of original image and to accelerate image discriminating processing. SOLUTION: A copying machine 1 has 1st and 2nd sensors 21 and 22 provided on the upstream side of contact glass 4 so as to successively discriminate the images on the surfaces of originals conveyed onto the contact glass 4 and a control part 30 for switching the reading threshold value of image reading part under the contact glass 4 into two stages at least. One threshold value is a reading threshold value enough for discriminating the image on the rear side surface of original defined as a discriminating object at least. Thus, the presence/absence of images on both the sides of original can be discriminated without turning out the original and further, by performing mirror processing to the image on the rear side surface, the original can be copied without being turned out. |
