READING DEVICE AND IMAGE FORMING APPARATUS

To provide a reading device that appropriately detects an edge position of a medium and appropriately corrects the attitude (registration amount and skew amount) of the medium, and an image forming apparatus.SOLUTION: An image forming apparatus comprises: a sheet conveying unit 210 of a main control unit 301 that conveys a medium; one or more reading units that read a sheet conveyed by the sheet conveying unit; and a reading parameter calculation unit included in a sheet attitude detection unit 220 that adjusts and updates setting values of the one or more reading units based on a result of comparison between read values of a background area of the sheet read by the one or more reading units and a preset read value of a background area of a sheet of the same type. The one or more reading units perform reading of the medium conveyed by the sheet conveying unit again based on the adjusted and updated setting values.SELECTED DRAWING: Figure 5 【課題】媒体のエッジ位置を適切に検出し、媒体の姿勢（レジスト量及びスキュー量）を適切に補正する読取装置及び画像形成装置を提供する。【解決手段】画像形成装置は、媒体を搬送する主制御部３０１の用紙搬送部２１０と、用紙搬送部により搬送される用紙を読み取る、一つないし複数の読取部と、一つないし複数の読取部で読み取った用紙の地肌領域の読取値と、予め設定された同じ種類の用紙の地肌領域の読取値と、の比較結果に基づき、一つないし複数の読取部の設定値を調整及び更新する、用紙姿勢検出部２２０が備える読取パラメータ算出部と、を備える。一つないし複数の読取部は、調整及び更新された設定値に基づいて、用紙搬送部により搬送される媒体の読み取りを再度行う。【選択図】図５