1. An electronic device for correcting a positional deviation between a plurality of images obtained in time series and performing synthesis processing on the plurality of corrected images, the electronic device comprising: a motion vector determination unit that determines a motion vector between the plurality of images; an image synthesis unit that corrects the positional deviation between the plurality of images based on the determined motion vector and generates a synthesized image by synthesizing the plurality of images subjected to the positional deviation correction; a filter area extraction unit that extracts a filter area in which filter processing is to be performed based on a degree of inconsistency occurring when the positional deviation between the plurality of images is corrected; a filter kernel determination unit that determines a filter kernel based on an imaging condition of an image pickup device; and a filter processing unit that performs filter processing based on the filter kernel on the extracted filter area of the synthesized image; wherein the filter kernel determination unit determines a degree of blur by obtaining values of a focal length, an F value, an object distance, and a background distance upon acquisition of the plurality of images, and determines the filter kernel based on the determined degree of blur.