In this tutorial we will use the Replicator filter under Building Blocks/Geometry in the Styles Browser to create a new image made up of tiny stars that starts from an ordinary photograph, such as this one of a sunflower.
Load the photograph you want to change from the File menu and then switch to the Style Editor. It will show up as an Image Source Filter node containing its thumbnail image. Insert a second Image Source Filter from Generators/Sources. This will be the image you will replicate throughout your photograph.

Select this second Image Source node and in the Properties+Preview pane select the Image Path, which will be the folder location of this second image on your computer or external storage location. It will appear in the preview pane on the right. We have chosen to use star.gif.

Insert the Replicator filter into the workspace with a double-click on the filter (click here to see how). Connect the Image Source Filter's image pin (from the star gif) to the Source Image pin of the Replicator filter (1) and then connect the Image Source's output pin (from the sunflower) to the Color Map pin (2) and finally, connect the Replicator's output pin to Layer #1 on the right side of the editor (click here to see how). Having the secondary Image source (the sunflower) connected to the Color Map will make sure that the replicated image of the star maps the original colors of the sunflower to the final image.

Change the Replicator's properties to best fit the image. Suggestions include increasing the Size and the Number of instances and/or changing the various jitter properties if you want. The sunflower's new image is now being generated as if was made up of small stars.

By changing only a small amount of the property settings in the Replicator filter, here are two examples of what you can get as a result: