A system for transmitting images, including: a base server being situated at a point where an image is to be taken, and being connected to an imaging device; and an aggregation server being connected to the base server through an electrical communication channel, the base server including: reference image transmitting means for transmitting image data (hereinafter, referred to as "reference image data") of a frame acting as a reference (hereinafter, referred to as "reference frame") to the aggregation server at a predetermined timing among images of a plurality of consecutive frames sequentially obtained through the imaging device; extracted area computing means for obtaining an image (hereinafter, referred to as "background image") acting as a background among images of a plurality of consecutive frames sequentially obtained through the imaging device, and sequentially computing a rectangular third area surrounding both a rectangular first area and a rectangular second area for each of frames individually following the reference frame selected among a plurality of consecutive frames sequentially obtained through the imaging device, the first area surrounding an area in which a difference is generated between an image of the each of frames and the background image, the second area surrounding an area in which a difference is generated between an image of a frame immediately prior to the each of frames and the background image, wherein a threshold is used to judge whether such a difference is generated; and extracted image transmitting means for sequentially extracting image data of the third area out of the each of frames, and transmitting the thus extracted image data to the aggregation server, the aggregation server including image synthesizing means for synthesizing a moving image based on the reference image data transmitted from the base server, and the image data of the third area extracted out of the each of frames. a base server being situated at a point where an image is to be taken, and being connected to an imaging device; and an aggregation server being connected to the base server through an electrical communication channel, the base server including: reference image transmitting means for transmitting image data (hereinafter, referred to as "reference image data") of a frame acting as a reference (hereinafter, referred to as "reference frame") to the aggregation server at a predetermined timing among images of a plurality of consecutive frames sequentially obtained through the imaging device; extracted area computing means for obtaining an image (hereinafter, referred to as "background image") acting as a background among images of a plurality of consecutive frames sequentially obtained through the imaging device, and sequentially computing a rectangular third area surrounding both a rectangular first area and a rectangular second area for each of frames individually following the reference frame selected among a plurality of consecutive frames sequentially obtained through the imaging device, the first area surrounding an area in which a difference is generated between an image of the each of frames and the background image, the second area surrounding an area in which a difference is generated between an image of a frame immediately prior to the each of frames and the background image, wherein a threshold is used to judge whether such a difference is generated; and extracted image transmitting means for sequentially extracting image data of the third area out of the each of frames, and transmitting the thus extracted image data to the aggregation server, reference image transmitting means for transmitting image data (hereinafter, referred to as "reference image data") of a frame acting as a reference (hereinafter, referred to as "reference frame") to the aggregation server at a predetermined timing among images of a plurality of consecutive frames sequentially obtained through the imaging device; extracted area computing means for obtaining an image (hereinafter, referred to as "background image") acting as a background among images of a plurality of consecutive frames sequentially obtained through the imaging device, and sequentially computing a rectangular third area surrounding both a rectangular first area and a rectangular second area for each of frames individually following the reference frame selected among a plurality of consecutive frames sequentially obtained through the imaging device, the first area surrounding an area in which a difference is generated between an image of the each of frames and the background image, the second area surrounding an area in which a difference is generated between an image of a frame immediately prior to the each of frames and the background image, wherein a threshold is used to judge whether such a difference is generated; and extracted image transmitting means for sequentially extracting image data of the third area out of the each of frames, and transmitting the thus extracted image data to the aggregation server, the aggregation server including image synthesizing means for synthesizing a moving image based on the reference image data transmitted from the base server, and the image data of the third area extracted out of the each of frames.