Medium-feeding apparatus, image reading apparatus, and medium-feeding method

A medium-feeding apparatus comprising:

• a medium mounting section on which a medium is to be mounted;
• a feeding roller configured to feed the medium mounted on the medium mounting section in a feeding direction;
• a movement detector disposed upstream of the feeding roller in the feeding direction, the movement detector being configured to output information on movement of the medium in a first direction parallel to the feeding direction and in a second direction intersecting the feeding direction;
• and
• a control unit configured to control feeding of the medium in accordance with the information acquired from the movement detector, wherein
• the control unit is configured to perform abnormal feeding processing depending on the movement of the medium in the second direction, wherein
• in the abnormal feeding processing, the control unit stops feeding of the medium when a first value indicating the movement of the medium in the first direction is within an allowable range and a second value indicating the movement of the medium in the second direction exceeds a threshold, and
• continues feeding of the medium when the first value is outside the allowable range.