I've been using the following zoom commands when making image videos:

Zoom in:
Code:
ffmpeg -loop 1 -i input.jpg -vf "zoompan=z='min(zoom+0.0015,1.5)':d=125" -c:v libx264 -t 5 -s "800x450" zoomin.mp4
Zoom out:
Code:
ffmpeg -loop 1 -i input.jpg -vf "zoompan=z='if(lte(zoom,1.0),1.5,max(1.001,zoom-0.0015))':d=125" -c:v libx264 -t 5 -s "800x450" zoomout.mp4
These zoom to/from the image's corners but I'd like to try to zoom to/from a specific part of the image.
i.e. starting with a close-up of someone's face then panning-out to show them standing in front of a famous landmark. (or vice-versa panning-in)

Is this possible? Does anyone know how to go about it?