Patent ID: 7738737

Claim:
An image processing apparatus, comprising: an input unit that inputs document data; an image reduction unit that sequentially reduces a document expressed by document data that has been input, while changing a reduction factor in stages; a reduction factor specification unit that refers to the characters that constitute the document that has been reduced with the respective reduction factors, and specifies the largest reduction factor at which blank regions surrounded by line portions that express each character do not disappear; a resolution specification unit that specifies a resolution of the characters for the reduction factor that has been specified; and a resolution conversion unit that converts a resolution of the document data that has been input by the input unit to the resolution that has been specified by the resolution specification unit, wherein the reduction factor specification unit: captures character regions from the document before being reduced by the image reduction unit; of the regions that are surrounded by line portions in each character region that has been captured, specifies regions larger than a predetermined size as the blank regions; counts a number of the blank regions in the document before being reduced and in the document that has been reduced with the respective reduction factors; specifies the smallest reduction factor at which the number of blank regions in the reduced document is less than the number of the blank regions that has been counted before reduction of the document; and specifies, as the largest reduction factor at which the blank regions surrounded by the line portions that express each character do not disappear, a reduction factor that is one step less than the smallest reduction factor at which the number of the blank regions in the reduced document is less than the number of the blank regions that has been counted before reduction of the document.