1. An imaging device comprising: an imaging section imaging a field to generate main photographic image data at the time of releasing and generating moving image data at the time of waiting main shooting; a region specifying section, based on said moving image data, specifying a main subject region containing a main subject and a background region other than that, of said main photographic image; and an image processing section performing image processing on said main photographic image data different from each other between said main subject region and said background region.