Fig. 1A–G.

(A) A DICOM image after optimal brightness and contrast adjustment, (B) adaptive histogram equalization filter, (C) triple gray filter, (D) color filter, (E) bone filter, and (F) Retinex filter images of a nondisplaced subcapital fracture are shown. This fracture was not diagnosed at presentation to the emergency room. (G) One day after the first radiograph was taken, the patient presented to the emergency room with a displaced subcapital fracture. In the DICOM image, the image brightness is not equal, whereas with the histogram equalization filter the brightness of the image is equally distributed. With the triple gray filter the image was parted into three zones and rebuilt, whereas with the color filter the image was parted into seven zones and rebuilt. The color filter was dropped after the pilot study. With the bone filter the bony trabeculae are enhanced, whereas with the Retinex filter bone elements are enhanced according to a multiscale level.