IMAGE DISPLAY SYSTEM, PORTABLE TERMINAL DEVICE, CONTROL METHOD, AND CONTROL PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide an image display system capable of accurately hiding part of an image when displaying the image, and provide a portable terminal device, a control method and a control program.SOLUTION: The image display system performs the steps of: detecting a first colored portion 33 which is colored with a first color and a second colored portion 34 which is colored with a second color in image information of a sheet 21 captured by an imaging section 5; defining a masking area 32 with respect to a display area 12 on the basis of the detected first colored portion 33 and second colored portion 34 when the distance between the first colored portion 33 and the second colored portion 34 are closer than a predetermined distance; displaying the image information of the sheet 21 in a display section 6; displaying a masking image 35 over the masking area 32; and stop displaying the masking image 35 on the basis of a touch on a touch panel 7.