Hi Old Fox,
Yes, in Qimage it's called a frame which is applied in the editor in the CUTOUT  but you can makesection. See attached screen shot.
There are a limited number of frames in the cutout collection but you can make your own, either in Qimage or, for more elaborate ones in a graphics/editor program.
See Qimage help for the rules about creating these: List of major functions - cutouts.
You have shown one example with an actual image which I assume you did in some other editor. Repeat that with a pure black image instead, save as filename.frame.tiff at say a size of 1500 pixels and copy to the Qimage cutouts folder. You can use that for ever more and not have to create a new image in some other program.
Most of my collection of cutouts & frames is illustrated here http://www.pbase.com/tjm04/cutout with one example from there below:



Terry

You can make the cutout square to fit all aspect ratios but because the frame is stretched around the image, there is some variation in width top-bottom to sides.
I usually make a frame with an aspect ratio of 4:3, one landscape and one portrait format and then the width variation around the frame is very small. You may need to make a "special" for panoramas
Terry