<description>This parameter determines what is detected as detail and thus preserved. To see what detail areas will be preserved, use the 'mask' parameter.</description>
<description>This is the number of iterations of a 3x3 averaging blur to be performed on the areas to be smoothed. It is applied only to the non-detail areas as determined by the 'threshold' parameter, and smoothing does not cross image detail. The filter becomes much slower as the strength is raised.</description>