I have 3840 × 2160 videos where I want to cut out a moving person on stage (e.g. music video). The crop area is fixed (1080 x 1920). The problem is, the person is moving around. Not much, but in a 3min. video the crop area would move a couple of times.
Example: Frame 0-889, area(500,34,1080,1920) - Frame 950-1735, area (800,10,1080,1920) - Frame 1820-2530, area(600,40,1080,1920)
I gave some example numbers above. The solution should interpolate the crop area between Frame 889 and Frame 950; Frame 1735 and Frame 1820. Ideally I would like to define those areas in a visual editor which allows me to move a fixed size crop rectangle for the Frames and coordinates given above.
Optionally I could also figure out the crop areas without visual help and then use that data to crop the video in something like ffmpeg (although I don't know how to do this properly including the interpolation step).
I am on Linux and tried different video editors but their crop filters are not useful to solve my task. I have Windows available but no commercial editing software installed at the moment.
Thanks for the help!