Digitized X-ray enhancement by pixel ordering

The main diagnosis tool in the evaluation of the hip prosthesis fit in total hip arthroplasty (THA) procedures are the X-ray film images. In order to design a computer aided diagnosis tool, the first step is to digitize the film images. A simple way of doing this is to take pictures of the X-ray film with a digital camera. We propose a method for the enhancement of the often poor-quality and reduced dynamic range digital images of the Xray film and for the increase of their dynamic range by using a strict ordering relation and a histogram specification technique.