load image - print it on large format epson printer

This is what I need. Load a jpeg or tiff. The jpeg or tiff is always 12" wide or high. (assume 300 dpi so one side will be always 3600 pixels.). Rotate if necessary so that the 12" part is the height of the image. then print the image (large format epson printers). Here's the tricky part that I can't figure out...to get the epson printer driver to advance the paper (CUSTOM PAPER SIZE) to match the image size WITHOUT going into the printer driver and setting the size manually. The paper roll size is 12" (not sheets) .The first part is trivial the 2nd part (changing paper size programatically) I cannot figure out. Realize that epson will always add 3mm advance before and after the print. Can you help me with this? This must be in vb.net or vb6