Adaptive movable window enhancement in digital chest radiography

The global linear min-max windowing is the most common clinical method of contrast enhancement, but it is inadequate for chest images because of wide dynamic range. Here, a method of local contrast enhancement is described, which uses a movable window. This technique automatically calculates the local histogram over the movable window, the maximum and minimum of the gray-level window based on the local cumulative distribution function (CDF) without manual intervention.