To correct the light quantity unevenness of the photographed image of various exposure levels.

A model code is read from a photographic film and a light quantity correction value is calculated by using a light quantity correction parameter corresponding to this model code. The photographed image of the photographic film is read and the image data meeting its density is specified from the model code and is converted to an exposure by a density-exposure conversion table. The exposure increased or decreased by the light quantity correction value is converted to corrected image data by the density-exposure conversion table. The density-exposure conversion table is formed by every kind of the photographic films in accordance with the film characteristics of the photographic films.