Patent ID: 11956392
Assignee: RICOH COMPANY, LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H  B | IPC B  H

Claim 2:
3. The image forming apparatus according to claim 1,
wherein
the program instructions further cause the processor to
detect the front edge of the mark based on a second threshold set between a brightness value of a background color of the recording medium and a brightness value of the mark, and
calculate a position of the front edge in a width of the front line based on a product of a ratio and a detected value difference, the ratio being a ratio between (i) a difference between a brightness value of the front line and a brightness value of an immediately preceding front line that is a line immediately preceding the front line and (ii) a difference between the brightness value of the immediately preceding front line and the second threshold, the detected value difference being a difference between (iii) a detected value output from the detector corresponding to the front line and (iv) a detected value output from the detector corresponding to the immediately preceding front line.