It is a progression from some of the filters in the original application.
Edit By BS Editor: It is a progression from some of the filters in the original application and allows you to Create an image with up to eight different colours or, if you want, to preseve parts of the original image.

Once an image has been loaded the transition points are set with the Sliders at the bottom of the screen. The colour that will appear Between the points set is shown in the colour patch between the sliders, clicking on this will open a colour chooser that allows you to pick any colour you want. It is not necessary to use all eight colours, in FACT fewer usually produce a more pleasing result, to use fewer just MOVE sliders at the ends to the top or bottom. A slider cannot be moved below one to its right, if a slider passes another the this one will be moved to the same value. If the checkbox beside a colour patch is ticked then the colour will not be used and the original image will be used between these points. you can free download Posteriser 2.0.2 now.