The Save With Special Options screen provides additional choices for saving images at customized sizes.  The Save a Tiled Image of the Specified Size option allows for creation of an image that is tiled to fill any specified Image Width and Height, optionally with Center Tiles or Mandala enabled.  The Large Source Image Save Options portion of the screen is available when the source image for the current effect is larger than the screen dimensions (otherwise this area is disabled and grayed).  The Upscale Window can be used to display an upscaled image before saving.  When saving a PNG format image, a Transparent Color can optionally be specified.  The Resolution value that is stored with some image formats can be set to a specified DPI (dots or pixels per inch), though changing the Resolution will not alter the quality of an image.