The presence of possibility of occurrence of an excessive adaptation due to use of only learned training data is detected during a learning stage. The user is urged to add data and other information, thereby avoiding the excessive adaptation. For this purpose, the invention has: an inputting unit for inputting a learning image; a generating unit for generating a discrimination model used to decide whether or not a target is normal on the basis of the learning image; a deciding unit for deciding whether or not the number of input learning images is insufficient when the discrimination model is generated; and a notifying unit for notifying a message for urging the user to add the learning image when it is decided that the number of input learning images is insufficient.