Patent attributes
An image reading apparatus is provided which is capable of preventing abnormal lines from being generated on an image read out from an original document even if there is more or less dirt attached to a reading glass exclusively used for reading ADF original documents. In an image reading apparatus 100 of the present invention, in case of dirt adhering to a reading glass 11, when an original document 13 being sent to a document reading position PW by a transportation part 12 of an automatic document feeder 10 is being read by a scanning carriage 23 through the reading glass 11, abnormal densities appear in pixel data of positions corresponding to the dirt among the readout pixel data. However, a control part 30 of the image reading apparatus 100 nullifies the pixel data of abnormal densities, and compensates for the nullified pixel data based on their surrounding pixel data. As a result, even when dirt adheres to the reading glass, there can be created an excellent image with no missing pixel without appearance of any abnormal black line.
