To enable a user to recognize printing results without going to the installation site of the printer.
A printer apparatus 2 performs printing according to a printing command transmitted from a client via a network and reads the image of the printed sheet by a scanner so as to obtain printing result image data. The printer apparatus 2 first detects the sheet state such as inclination of the sheet and folding/overlapping from the contents of the printing result image data and determines the quality of the printing results from the detection results. When a sheet having a low light reflectance is used as a backing sheet of the part of the sheet where image is read for the quality determination, more precise determination results can be obtained.
Nobuo Suzuki
Wachi Shigeaki