The “Increase Resolution” filter is commonly used to print large prints from small images. It first doubles (or quadruples) the width and height of the image to produce the “Intermediate” image (see below), and then uses advanced interpolation techniques to remove the “pixelated” effect. For a low resolution image, it produces a much better result than simply increasing the image size through Photoshop or similar image editing apps.
There are three different filter types: Normal, Harder and Softer. If you have a high quality picture, you can choose Harder. If you have a low quality picture, you should choose Softer.
The Increase Resolution filter is available in the stand-alone program but is not yet available in the plugin.