Patent ID: 8639010

Claim:
A radiographic apparatus comprising an image correcting unit for correcting offset of a detection value for every pixel to output corrected image data, the detection values being outputted from a radiation detector having pixels for detecting radiation arranged in a two-dimensional array, wherein the image correcting unit comprises: an offset-pammeter calculation unit calculating offset parameter as a time average of the detection values for every pixel upon taking dark images; a fluctuation-noise calculation unit calculating a fluctuation noise that is a standard deviation of the detection values for every pixel upon taking dark images; a correction constant calculation unit calculating a correction constant from the fluctuation noise for holding a negative value of a noise amplitude; an offset correcting unit calculating an offset correction value by subtracting the offset parameter from the detection value at which a subject is imaged and adding the correction constant; and a gain correcting unit calculating corrected image data through multiplying a value, obtained by subtracting the correction constant from the offset correction value, by a gain correcting coefficient for correcting differences of the pixels in detecting property and then adding the correction constant, and wherein the image correcting unit corrects the offset while holding noise components contained in the detection value.