Canon imagePROGRAF GP-4000 - Manual (Page 695)

I want to easily create vertical or horizontal banners
You can print originals that are in landscape (or portrait) orientation automatically enlarged to fit the roll
width. This is an easy way to create vertical or horizontal banners.
Printing Hanging and Horizontal Banners (Large-Format Printing) (Windows)
Printing Hanging and Horizontal Banners (Large-Format Printing) (macOS)
695