1. An image processing device comprising: a region divider configured or programmed to divide an image into a predetermined region according to a parallax value with respect to each pixel of the image, and convert the parallax value for each region; a map filtering processor configured or programmed to apply filtering to the parallax map based on the parallax value converted by the region divider; a filtering magnitude selector configured or programmed to select a magnitude of an image filtering corresponding to the parallax map applied with the filtering by the map filtering processor; a blurred image generator configured or programmed to generate a blurred image of the image by applying the image filtering to the image; and an image composer configured or programmed to generate a composite image obtained by compositing the image and the blurred image based on the parallax map after the filtering by the map filtering processor.