Patent ID: 7877135

Claim:
An image data processor, comprising: an image signal receiver that receives an autofluorescence image signal generated by an imaging device when said imaging device captures an autofluorescence image, the autofluorescene image being an optical image of an object illuminated by an exciting light that makes an organ generate autofluorescence; a histogram generator that generates an autofluorescence histogram, the autofluorescence histogram being a histogram of luminance in said autofluorescence image based on said autofluorescence image signal; a gain calculator that calculates an autofluorescence gain used for amplifying said autofluorescence image signal based on said autofluorescence histogram and a predetermined luminance value for said autofluorescence image signal, wherein said autofluorescence gain is calculated so that one of an average luminance value and a maximum luminance value in said autofluorescence histogram amplified by said autofluorescence gain corresponds to said predetermined luminance value; an amplifier that generates an amplified autofluorescence image signal by amplifying said autofluorescence image signal by said autofluorescence gain; and a signal feeder that can output said amplified autofluorescence image signal to a monitor that displays an amplified autofluorescence image corresponding to said amplified autofluorescence image signal.