Sheet processing apparatus and method

An image forming system comprising:

• a sheet feeding unit configured to feed sheets of different sheet sizes;
• a cutting unit configured to cut an edge portion of a fed sheet;
• a folding unit configured to fold the sheets a number of times;
• a calculation unit configured to calculate a sheet utilization efficiency for each of the different sheet sizes based on the difference between an area of the sheet before cutting and the area of the sheet after cutting the edge portion by the cutting unit;
• and
• a sheet size selection unit configured to select a size of sheet to be fed based on a result of calculation with respect to the sheet utilization efficiency for each of the different sheet sizes,
• wherein the sheet size selection unit selects a size of sheet to be fed based on the area of the sheet before cutting by the cutting unit and folding by the folding unit, and the area of the sheet after folding the sheet by the folding unit and cutting the edge portion by the cutting unit.

An image forming system, comprising:

• a folding unit configured to determine a number of times to fold a sheet based at least upon a length of the sheet in a conveyance direction and a cutting margin;
• a division unit configured to determine a number of times to divide the sheet based at least upon a length of the sheet in a direction orthogonal to the conveyance direction and the cutting margin subsequent to determining the number of times to fold the sheet;
• a cutting unit configured to cut an edge portion of the sheet subsequent to the division unit determining the number of times to divide the sheet;
• and
• a calculation unit configured to calculate a sheet utilization efficiency based on an area of the sheet before cutting and the area of the sheet after cutting the edge portion by the cutting unit.