Mark sheet image processing system

An image processing system comprising:

• a processor;
• and
• memory configured to store instructions that, when executed by the processor, cause the processor to:
• analyze a mark sheet that includes a plurality of sets of a character string representing an item, and a frame arranged in a first direction with respect to the respective character string and whose inside is filled in when the item represented by the character string is selected, the plurality of sets being arranged in a second direction perpendicular to the first direction;
• and
• identify a filled-in frame, which is the frame whose inside is filled in, from an area image that is an image of the area among images read from the mark sheet by an image reading device by:
• generating a first image by removing from the area image at least elements that are in contact with a boundary of the area image;
• generating a second image by removing from the first image at least elements whose area is equal to or smaller than a specific ratio, less than 1, of an area of the largest element in the first image;
• identifying an element in the second image as a blank frame, whose inside is not filled in;
• identifying an element among elements in the area image whose position in the first direction is within a specific distance of the position of the blank frame as the frame;
• and
• identifying the frame for which there is no corresponding blank frame within the specific distance as the filled-in frame.