An algorithm for enhancement of noisy X-ray images

A simple and fast algorithm for enhancement of noisy images is presented. It can be utilised as a preprocessing step for an automatic image analysis. The quality of an image is improved by reducing available noise and simultaneously increasing the contrast without increasing the overall dynamic range. An identification of what type of enhancement is adequate at different image locations is attempted. The image is divided into blocks which are classified into four different types. Different enhancement procedures are applied for the different types of blocks.