1. A still image display device comprising: a recording medium for recording an in-focus image and an out-of-focus image obtained by imaging an identical object; the still image display device performing the functions of: reading said in-focus image and said out-of-focus image from said recording medium, calculating a blur evaluation value based on a difference between high frequency components contained in said in-focus image and said out-of-focus image, evaluating the degree of blurriness of said out-of-focus image relative to said in-focus image by comparing said blur evaluation value with a predetermined reference value, choosing a first mixture ratio set in a case where said blur evaluation value is evaluated to be equal to or more than said reference value, and choosing a second mixture ratio set in a case where said blur valuation value is evaluated to be less than said reference value, provided that said first mixture ratio set refers to one set having a gradually varying mixture ratio for mixing said in-focus image and said out-of-focus image, and said second mixture ratio set refers to one set having a higher mixture ratio of said in-focus image and a lower mixture ratio of said out-of-focus image than said first mixture ratio set, and generating a plurality of mixed images from said in-focus image and said out-of-focus image read out of said recording medium in accordance with a chosen one of said first and second mixture ratio sets; a display that displays said mixed images; and a display controller that sequentially displays said plurality of mixed images on said display.