Patent ID: 8237997
Filing Date: 2012-08-07
Classification: G06T,H04N

Abstract:
1. An image reader, comprising: a document transport unit which transports a document; a reading unit which executes a read operation in a main-scanning direction at a predetermined reading position, and is capable of reading an image of a document which passes the reading position in a sub-scanning direction during transportation by the document transport unit; a striped image detection unit which detects a striped image generated by a presence of a foreign substance adhering to the reading position, based on an image that the reading unit has read in a predetermined position between documents transported through the reading position by the document transport unit; an average calculation unit which calculates an average of pixel values of pixels constituting the image of the document read by the reading unit, the pixels being in positions corresponding to the striped image detected by the striped image detection unit; a judgment unit which judges whether the average calculated by the average calculation unit is in a predetermined range; and a correction unit which performs a first correction processing to replace a pixel value of each pixel that constitutes the read image of the document by the reading unit and that is located at a position corresponding to the striped image, with a pixel value determined by a pixel value of a pixel around the pixel or with a predetermined pixel value, when the judgment unit judges that the average is outside the predetermined range, and performs a second correction processing to correct a pixel value of each pixel that constitutes the read image of the document by the reading unit and is located at a position corresponding to the striped image by using the pixel value of the pixel, when the judgment unit judges that the average is within the predetermined range.