1. A system for processing an image, comprising a region detector comprising an artifact detector for detecting a region comprising an artifact in the image; a parameter determining unit for determining a parameter, based on a portion of the image excluding the detected region; and an image processing module for processing the image, using the derived parameter; characterized in that the system further comprises user interface ( 8 ) to enable a user to visualize both the image and the artifact excluded during the processing of the image.