How can I center the image on a page? I want images to cover the page completely, and since they have proper size (roughly A4), I only need them to be centered. Now they are stuck to the top, leaving a gap on bottom (and same for left-right).
I have the following script (note my Lua trick to process images in a batch). Image names are "Image00001.png" and so on.
for n = 1, 9 do