1. A radiographic imaging system including a plurality of radiographic imaging apparatuses each configured to acquire a radiographic image based on radiation emitted from a radiation source and a processing unit configured to combine a plurality of the radiographic images acquired from the plurality of radiographic imaging apparatuses to generate a stitched image, the radiographic imaging system comprising: a correction image data determination unit configured to determine correction image data based on an irradiation condition of radiation emitted from the radiation source; and an image correction unit configured to correct an area of the stitched image corresponding to an area in which the plurality of radiographic imaging apparatuses overlap each other, by using the correction image data.