1. An image processing device for generating a high resolution image from first to N-th low resolution images, where N is an integer equal to or greater than two, the image processing device comprising: a positional offset calculator for calculating a positional offset between the first low resolution image and each J-th low resolution image, where J is an integer ranging from two to N; a combiner for obtaining a combined pixel array in which pixel values of pixels in the first to N-th low resolution images are assigned to pixels arrayed on a common plane on the basis of the positional offsets, and obtaining valid pixel flag data indicating whether or not each pixel on the common plane has been assigned a pixel value from the first to N-th low resolution images; and a pixel value calculator for obtaining a pixel value of each pixel in the high resolution image from an interpolation operation based on the pixel values of the pixels in the combined pixel array, using, for each pixel of interest set on the common plane, pixel values of pixels in an area of interest set to include the pixel of interest; wherein the pixel value calculator includes an interpolation coefficient calculator for obtaining, for the pixels in the area of interest, interpolation coefficients with values that increase with increasingly strong correlation with the pixel of interest; and an interpolation operation unit for performing the interpolation operation by using the interpolation coefficients and the pixel values of the pixels in the area of interest.