UPDATE: Hello there. This stream has ended, and because it was longer than 12 hours youtube didn't archive any part of it. In fact, the stream lasted unbroke...
It’s easy to do this with a computer and no AI. Just have a recording of him saying each individual number and then get the computer to read the relevant recording while going through the digits of PI. You could have a number of recordings for each number and choose one randomly to simulate variation.
Crazy times we live in that my first instinct was “what a clever use of AI” only to read the description to see that no AI was used!
It’s easy to do this with a computer and no AI. Just have a recording of him saying each individual number and then get the computer to read the relevant recording while going through the digits of PI. You could have a number of recordings for each number and choose one randomly to simulate variation.
Although that will require some mastery on the actor’s part to allow for it to be edited well without special effects
Edit: watched the stream after commenting, since we can’t see the actor, there is no need for editing the video, that makes it simpler, true