1. An image display apparatus for a vehicle, a seat of a driver of which is adjacent to a first side, which is one of a right side and a left side of the vehicle, the apparatus comprising: a first camera for producing first image data corresponding to a first outer region rearward of the vehicle; a second camera for producing second image data corresponding to a second outer region outward of a second side opposite to the first side of the vehicle, the second outer region having an overlap with the first outer region; a display arranged inside the vehicle for displaying an image of a part of the first outer region and the second outer region; an image processing unit for processing the first image data and the second image data to produce processed image data corresponding to an integrated region, which includes a part of the first outer region and the second outer region without the overlap and is viewed by an artificial sightline of the driver, which is assumed to pass through the display to reach the integrated region so that the integrated region is visible for the driver; a display control unit for causing the display to reproduce an image of the integrate region using the processed image data; and a storage unit for storing shape data specifying an outer shape of each sub-display, and position data specifying arranged positions of each sub-display, wherein the display includes a plurality of sub-displays arranged inside the vehicle, the sub-displays being adjacent to each other, the processed image data includes a plurality of data items, the integrated region includes a plurality of sub-regions, the image processing unit clips the first image data and the second image data to produce each data item corresponding to each sub-region, which is viewed by the artificial sightline of the driver, which is assumed to pass through each sub-display to reach the each sub-region, the display control unit causes the each sub-display to reproduce an image of the each sub-region using the each data item, the image processing unit clips the first image data and the second image data by referring to the shape data and the position data stored in the storage unit, and the display control unit causes the each sub-display to reproduce an image of the each sub-region using the each data item, the image being displayed without an overlap with an image reproduced in a sub-display adjacent to the each sub-display.