A portable electronic apparatus configured to be battery-powered and to display a visual program received from the outside is provided. The portable electronic apparatus has a receiver configured to receive EPG data related to the program, a battery power estimator configured to estimate remaining battery power, an image processor configured to process an image included in the program by using a plurality of functions of image quality control, and a controller configured to set how to use each of the functions by means of the image processor. The controller is configured to estimate battery lasting time on the basis of the remaining battery power, a setting of the use of the functions and the EPG data. The controller is configured to update the setting of the use of the functions upon judging the remaining battery power to be short of enough to display the program to the end.