If an iPhone screen recording, which is 1080 x 1920 (portrait size) is edited in iMovie or Final Cut Pro, and resaved as a final video, I noticed the video will be landscape: 1920 x 1080 with black bars at left and right.
It isn't a problem if viewed on a desktop computer, but if viewed in any mobile phone, then, the left and right black bars will "push" the video to be really tiny, about 1/9 of the screen size.
Is there a way to "preserve" the video as portrait: 1080 x 1920, so that there is no black bars, and so the video will be shown on mobile phone as the original 100% screen size, instead of 1/9 of screen?
(iMovie's crop must crop it as landscape size, and Final Cut's crop can do a crop, except when "Share" as file, the file saved is landscape size again.)
I can think of one way which is to use HandBrakeCLI to do a crop, but then can it and how can it be done in iMovie / Final Cut Pro?