Patent ID: 7782502

Claim:
A reading-characteristic correction method for an image reading device including a first reading unit configured to read one side of an original and a second reading unit configured to read the other side of the original, the reading-characteristic correction method comprising: causing the first reading unit and the second reading unit to read a monochrome reference original, and correcting gain and offset of a tone characteristic of the second reading unit, based on image data of the monochrome reference original read by the first reading unit and the second reading unit, such that the tone characteristic of the second reading unit matches a tone characteristic of the first reading unit; causing the first reading unit and the second reading unit to read a color reference original, and correcting, for individual color components, the offset of the tone characteristic of the second reading unit, based on image data of the color reference original read by the first reading unit and the second reading unit, such that differences between color read by the first reading unit and color read by the second reading unit are reduced.