INCLINATION AMOUNT DETECTION DEVICE FOR DOCUMENT, AND IMAGE PROCESSING APPARATUS

• Main Authors: KAWANO TAKUYA, HABA KENYA
• Format: Patent
• Language: English; Japanese
• Published: 15.06.2017
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; IMAGE DATA PROCESSING OR GENERATION, IN GENERAL; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION

PROBLEM TO BE SOLVED: To detect an inclination amount of a document with accuracy independent of the document and within a shorter time than prior arts.SOLUTION: A device disposed on a surface of a background plate and detecting an inclination amount of a sheet-like document passing on the surface comprises: a light source for irradiating the document with light; means for acquiring an input image through scanning for reading a region including at least one end side of the document; means for detecting a boundary point KT between the document and the background plate in the input image for each of multiple positions X in a main scanning direction M1; means for determining an attention boundary point group KTG consisting of a plurality of boundary points KT; means for determining a midpoint Pc of an inclination line La for approximating the end side of the document; means for setting a line that passes the midpoint Pc and is inclined relatively to the main scanning direction M1, as the inclination line La; means for changing the inclination amount of the inclination line La in such a manner that an error between the attention boundary point group KTG and the inclination line La is reduced; and means for determining an inclination amount of the inclination line La that makes the error equal to or less than a threshold, as the inclination amount of the document.SELECTED DRAWING: Figure 8 【課題】原稿に依存しない精度でかつ従来よりも短い時間で原稿の傾き量を検出する。【解決手段】背景板の表面に配置されまたは表面を通過するシート状の原稿の傾き量を検出する装置は、原稿を照射する光源と、原稿の少なくとも１つの端辺を含んだ領域を読み取る走査によって入力画像を取得する手段と、入力画像における原稿と背景板との境界点ＫＴを、主走査方向Ｍ１の複数の位置Ｘのそれぞれについて検出する手段と、複数の境界点ＫＴからなる注目境界点群ＫＴＧを定める手段と、原稿の端辺を近似するための傾き線Ｌａの中点Ｐｃを定める手段と、傾き線Ｌａとして、中点Ｐｃを通り主走査方向Ｍ１に対して傾いた線を設定する手段と、注目境界点群ＫＴＧと傾き線Ｌａとの誤差が小さくなるように傾き線Ｌａの傾き量を変更する手段と、誤差がしきい値以下である傾き線Ｌａの傾き量を原稿の傾き量として決定する手段と、を有する。【選択図】図８