Patent ID: 8422064

Claim:
An image-reading apparatus comprising: a power-on switch; a document plate where an original document is placed; a line image sensor that reads an image on the document plate by scanning to obtain image data; a reference-setting image that is placed outside a region of the document plate where the original document is placed and at a position where the line image sensor is able to read, wherein the reference-setting image includes a first pattern and a second pattern; and a control unit configured to set a reference position when the line image sensor reads the reference-setting image, wherein, when the power-on switch is turned on, the control unit selects a manner to read the reference-setting image depending on whether the control unit is in a power-on reset state or not, and wherein, not to read the reference-setting image is included in the selected manner when the control unit is not in a power-on reset state.