Image reading apparatus, non-transitory computer-readable medium for image reading apparatus, and method for controlling image reading apparatus

A non-transitory computer-readable recording medium storing computer-readable instructions for an image reading apparatus including:

• a platen configured to support an original;
• a reading device configured to optically read the original supported on the platen to obtain a plurality of line images for an entire image including an original image representing the original;
• and a processor, wherein the computer-readable instructions, when executed by the processor, cause the image reading apparatus to perform:
• controlling the reading device to start reading;
• before completing reading the entire image, determining whether the image to be obtained represents a book document spread open on the platen, the book document indicating a bound document;
• in a case where it is determined that the original image to be obtained represents the book document, determining whether a value satisfies a prescribed condition, the value being based on a difference between a first density distribution of an image in a first partial region of the entire image and a second density distribution of an image in a second partial region of the entire image, the first partial region including a part of a dark region, the dark region extending in an extending direction and an image in the dark region having a density larger than a prescribed density threshold value, the first partial region extending in a crossing direction crossing the extending direction, the second partial region including another part of the dark region and extending in the crossing direction, the second partial region being shifted from the first partial region with respect to the extending direction;
• in a case where the value satisfies the prescribed condition, controlling the reading device to interrupt reading the entire image;
• and
• in a case where the value does not satisfy the prescribed condition:
• controlling the reading device to continue reading the entire image so that all of the plurality of line images is read;
• and
• generating read data using the plurality of line images.

A method for controlling an image reading apparatus including:

• a platen configured to support an original;
• a reading device configured to optically read the original supported on the platen to obtain a plurality of line images for an entire image including an original image representing the original;
• and a processor, the method comprising:
• controlling the reading device to start reading;
• before completing reading the entire image, determining whether the image to be obtained represents a book document spread open on the platen, the book document indicating a bound document;
• in a case where it is determined that the original image to be obtained represents the book document, determining whether a value satisfies a prescribed condition, the value being based on a difference between a first density distribution of an image in a first partial region of the entire image and a second density distribution of an image in a second partial region of the entire image, the first partial region including a part of a dark region, the dark region extending in an extending direction and an image in the dark region having a density larger than a prescribed density threshold value, the first partial region extending in a crossing direction crossing the extending direction, the second partial region including another part of the dark region and extending in the crossing direction, the second partial region being shifted from the first partial region with respect to the extending direction;
• in a case where the value satisfies the prescribed condition, controlling the reading device to interrupt reading the entire image;
• and
• in a case where the value does not satisfy the prescribed condition:
• controlling the reading device to continue reading the entire image so that all of the plurality of line images is read;
• and
• generating read data using the plurality of line images.