Patent attributes
A printer detects a roll radius of a recording paper roll once a day and measures the remaining amount of recording paper. Then the printer calculates the number of photo prints in the previous day as an actual consumption value from a difference in remaining amount of paper between the day and the previous day. The printer stores the actual consumption values in the form of a calendar cumulatively and creates a consumption record of the recording paper. Next, the printer estimates predicted consumption of the recording paper in a coming week based on the consumption record. And the printer predicts the time of occurrence of a paper-out condition based on the remaining amount of the recording paper and the predicted consumption. When it is predicted that the printer will be out of paper within a coming week, the printer displays a warning message on a LCD and urges a supervisor of the printer to prepare a new recording paper roll.