Image reading apparatus and control program for image reading apparatus for determining output range of image data based on reference-range information of such image data

An image reading apparatus comprising:

• a scanner which reads an image recorded on a document to obtain image data of the image by scanning;
• an operable portion which is to be operated by an operator;
• an outputting portion which outputs the image data read by the scanner;
• a read-controlling portion configured to conduct a reading operation in which the scanner reads and obtains sections of the image data of the document, wherein parts of the image respectively corresponding to the sections of the image data are read in a reading order;
• an image-data storing portion which stores, in a memory, the sections of the image data read by the scanner in the reading order;
• a display device which displays a display image based on the sections of the image data stored in the image-data storing portion, the display image corresponding to the image recorded on the document;
• a reference-range-information storing portion which stores reference-range information that is required to determine a reference range of the image data, the reference range being a range of the sections of the image data that are stored in the image-data-storing portion and are to be displayed as the display image on the display device;
• a reference-range managing portion which determines, on the basis of the reference-range information stored in the reference-range-information storing portion, the reference range of the image data stored in the memory by the image-data storing portion and which successively updates the reference-range information such that the reference range successively changes by a prescribed size;
• a display controlling portion which controls the display device to display the display image in a manner that parts of the display image respectively corresponding to the sections in the reference range are displayed in the same order as the reading order on the basis of the reference-range information;
• a timing controlling portion which controls updating intervals at which the reference range is updated by the prescribed size, such that an amount of the image data that corresponds to the display image newly displayed in a certain time period is smaller than an amount of the image data newly stored in the memory in the certain time period;
• a command detecting portion which detects a specific command which is to be inputted through the operable portion;
• and
• an output-range determining portion which determines an output range of the sections of image data that are stored in the memory and are to be outputted by the outputting portion, on the basis of the reference range decided based on the reference-range information that is the most recently updated by the reference-range managing portion, when the specific command is detected by the command detecting portion.