Patent ID: 8416465

Claim:
A reader comprising: a reading unit configured to read image data on both sides of each of document sheets; a determining unit configured to make a determination as to whether a predetermined one of both sides of each of the document sheets is blank, based on the image data read by the reading unit; and a classifying unit configured to classify the image data read from each of the document sheets into one of different groups, based on the determination made by the determining unit; wherein the classifying unit comprises a mode changing unit configured to change a classifying mode from a first mode to a second mode in response to a predetermined instruction, wherein the classifying unit is configured to, in the first mode, classify the read image data into a predetermined one of the different groups, regardless of the determination by the determining unit, wherein the classifying unit is configured to, in the second mode, classify the read image data into one of the different groups, based on the determination by the determining unit, and wherein the classifying unit is configured to, immediately after the reading unit starts to read the image data of the document sheets, classify the read image data into the predetermined group in the first mode, wherein the classifying unit is configured to, in the first mode, classify the read image data into a first group, regardless of the determination by the determining unit, wherein the classifying unit is configured to, in the second mode, classify the read image data into one of the first group and a second group different from the first group, based on the determination by the determining unit, wherein the classifying unit is configured to, when the determining unit makes an initial determination that meets a requirement for the second group after the mode changing unit changes the classifying mode from the first mode to the second mode in response to the predetermined instruction, start to classify the read image data into the second group, and wherein the classifying unit is configured to, when the determining unit makes an initial determination that meets a requirement for the first group after the classifying unit starts to classify the read image data into the second group in the second mode, restart to classify the read image data into the first group, and cause the mode changing unit to restore the classifying mode to the first mode.