I am not sure what kind of extreme algorithm YouTube uses, but then by asking it to correct the shakiness in the video, it produces amazing results.
I had read about some mathematical transforms which work on digital signals, and that includes pics and videos, which enable us to modify them as needed. And I believe the engineering team of YouTube must have found out some great combination to produce fantastic results.
Leave it on Google to deliver the best, Always.
To check out an example, please see the following link.
