This changes the image so it looks like it is made up from square tiles. You can set the number of tiles to use both horizontally and vertically. You can alter the maximum and minimum gap between tiles (if the maximum and minimum are not the same, the gap for each tile will be a random value between them), for both vertical and horizontal gap. You can give the tiles an edge, and control it's thickness. You can alter the lighting effect on the tiles edges (horizontal and vertical), and you can specify how transparent the colour used in the gaps is.
There are no seperate options.