METHOD OF TREATING GRADATION OF XXRAY PICTURE OF BREAST AND ITS DEVICE

摘要

A method and apparatus for processing a frontal chest radiograph in a radiographic image copying system in which an original radiograph is scanned with a scanning light beam and the light transmitted through the radiograph is detected by a photodetector which gives an output to be processed and used for recording a visible image on a recording medium. The frontal chest radiograph is gradation processed. The gradation processing is characterized in that the density at the boundary of the heart and the lungs of the image on the recording medium is lowered to lower the contrast of the heart and raise the contrast of the lungs.