1. A document-image-data providing device which provides document image data to an information processing device, comprising: a document image inputting unit configured to input document image data; an area recognition unit configured to recognize respective areas of document image elements which constitute the document image data; an element data extracting unit configured to extract, when a document image element of the document image data is selected in the information processing device, element data of the selected document image element from the document image data, based on a corresponding one of the areas recognized by the area recognition unit; an element data providing unit configured to provide the element data extracted by the element data extracting unit, to the information processing device; an image generating unit configured to generate a first document image data having a first resolution lower than a resolution of the input document image data and a second document image data having a second resolution lower than the first resolution of the first document image data; an image providing unit configured to provide the generated second document image data having the second resolution to the information processing device; and a list providing unit configured to provide a list of the second document image data to the information processing device as a list of the document image data, wherein the image providing unit is configured to provide, when a second document image element is selected from the list of the second document image data, a first document image element corresponding to the selected second document image element as a preview image of document image data corresponding to the second document image data to the information processing device.