This script allows you to extract and apply saturation to a layer. When you extract, it adds a new layer with the saturation values (in gray colors). You can then use curves, brightness/contrast or the dodge tool to correct saturation. When you are okay with the adjustements you can put back the saturation by applying it.
This script will resize an image for printing, specifically it changes the pixels per inch setting and resizes the canvas. I did this so I could "resize" an image to have a full frame print. A white border will be created to pad the "short" edge.