User pano to get to equirectangular format with a 2:1 ratio

I am trying to add a user pano taken with my drone from above a property. I created the pano in a stitcher program (3D vista) and it came out in a 2.791x1 size dimension. Any suggestions on how to make it into a equirectangular format with a 2:1 ratio? Thanks!

The process of taking all those drone images and converting them into an acceptable equirectangular format is the reason I stopped working on this after experimenting with it: its time consuming and tedious!
I found a program called autostitch that does a good job of merging the drone images, but this resulting file still needs to be worked over in photoshop to fill in the “blank” areas above the drone to make a realistic pano.

Try adjusting canvas size in a photo editor to add required height to meet the 2:1 aspect ratio requirement. The simplest is to leave the added pixels grey or black, if you do not want to spend time filling them in from surrounding pixels. You will need to experiment with positioning the image vertically in that expanded canvas.