Best guess on first instance, about 20 ft horizontal clearance and 10-15 ft vertical clearance. That would be enough to get my attention, too!
This is based on flying my local area which is almost uninhabited but dense with very tall trees - I'm recalling the image of the trees when observing from the ground so I could see the clearance.
The second instance I'd guess you had 60 ft horizontal clearance. And FWIW I think you did a pretty good job of staying away from being directly above masses of people (I confess I stopped viewing after the second instance, so hopefully nothing dumb was shown after that!) - hard to avoid either people or cars completely if flying in an inhabited area.
Were you flying manually or on a planned mission in Litchi? One of my first tries in Litchi was a planned orbit of my house out in the woods. I walked around it, checked Google Earth very carefully and checked elevations. When the autonomous mission was flown exactly as planned, one of the propellers was close enough to a very large Douglas fir branch to blow the light new-growth branches out of its own way - the CAS cameras were pointing at the house, away from the tree, so didn't see it - if it had hit the main branch 2 inches further in, it would have been quite costly. THAT showed even careful planning can be a bit off! Took my heartrate a couple minutes to settle down.
If you have a decent ground-track record from Litchi, you might be able to zoom in and get a much better idea of horizontal clearance if you can spot the structures in satellite view.
