1. An image processing apparatus comprising: an image processing unit which performs image processing on each of a plurality of images of a same subject having different resolutions; and an image combining unit which combines an image processing result of each of the plurality of images obtained by the image processing unit, wherein the image processing unit performs different patterns of image processing on each of the plurality of images, wherein the image processing unit performs at least brightness noise reduction and chroma noise reduction as image processing, and wherein the image processing unit performs the brightness noise reduction on an image of a higher resolution than a resolution of an image on which the chroma noise reduction is performed.