IMAGE PROCESSING SYSTEM CAPABLE OF APPLYING GOOD TEXTURE SUCH AS BLUR

An image processing apparatus assumes the characteristic of a virtual image sensing optical system, and applies a blur effect corresponding to an in-focus state to a captured image. An image input unit captures image information including distance information to each portion of an object to be photographed. A parameter input unit inputs a parameter from which the effective aperture and focal length of the assumed image sensing optical system can be derived. An in-focal pint position designation unit designates the in-focal pint position of the assumed image sensing optical system. A blur state calculation unit calculates a blur state from the distance information input by the image input unit, the in-focal pint position designated by the in-focal pint position designation unit, and the parameter input by the parameter input unit. An image processing unit applies the blur effect to the image input by the image input unit in correspondence with the blur state calculated by the blur state calculation unit.