Document reading apparatus that corrects read image data

A document reading apparatus comprising:

• a tray on which a document can be placed;
• a conveyance unit configured to convey the document placed on the tray;
• a reading unit configured to read the document being conveyed in a conveyance direction by the conveyance unit to output first image data;
• an image processing unit configured to generate second image data from the first image data by image processing including correction processing of correcting the first image data based on correction data;
• a reference member;
• and
• at least one processor, wherein the at least one processor is configured to:
• set a reading operation parameter including a resolution parameter indicating a resolution in the conveyance direction and a resolution in a width direction orthogonal to the conveyance direction of an image indicated by the second image data,
• perform generation processing of generating the correction data by causing the reading unit to read the reference member, and
• control whether to set the resolution in the width direction when causing the reading unit to read the reference member to a first resolution or a second resolution lower than the first resolution based on one or more parameters regarding a size of a document included in the reading operation parameter in a case where the resolution parameter when performing the generation processing indicates the second resolution as the resolution in the width direction.