1. An image processing device comprising: at least one memory operable to store program code; at least one processor operable to read the program code and operate as instructed by the program code, the program code including: calculator code configured to cause at least one of said at least one processor to calculate a statistic of each of first material images among multiple initial images depicting an object; initializer code configured to cause at least one of said at least one processor to construct a volume of the object from multiple second material images and multiple second imaging directions associated respectively with the multiple second material images among the multiple initial images; estimator code configured to cause at least one of said at least one processor to estimate a statistic associated with an observation direction from the calculated statistics; render code configured to cause at least one of said at least one processor to render an image by observing the constructed volume in the observation direction; corrector code configured to cause at least one of said at least one processor to correct the rendered image based on the statistic estimated in association with the observation direction; and constructor code configured to cause at least one of said at least one processor to construct a volume of the object from at least the observation direction and corrected image.