According to the documentary, the group worked with film director Peter Jackson to obtain this AI program, which produced the final result.

Source: https://pjmedia.com/jon-del-arroz/2023/11/03/ai-reconstructing-john-lennons-vocals-for-a-new-beatles-song-is-creepy-n4923596

New Line Cinema and WingNut Films produced the trilogy, with Barrie M. Osborne, Peter Jackson, Fran Walsh, and Tim Sanders serving as producers (Sanders only for The Fellowship of the Ring).

Source: https://www.comingsoon.net/movies/news/1262808-the-lord-of-the-rings-trilogy-netflix-release-date-set-for-february

No filmmakers have been named yet, but Peter Jackson, Fran Walsh, and Philippa Boyens said in a statement that Warner Bros. and Embracer “have kept us in the loop every step of the way.”

Source: https://1010wcsi.com/entertainment-news/ellen-pompeo-megan-mullally-nick-offerman-more/?utm_source=rss&utm_medium=rss&utm_campaign=ellen-pompeo-megan-mullally-nick-offerman-more

Peter Jackson, he was still honing his craft in his home country of New Zealand and dabbling with a variety of genres.

Source: https://collider.com/peter-jackson-dead-alive-movie/

Still from the Peter Jackson Lord of the Rings: The Fellowship of the Ring movie adaptation.

Source: https://greekreporter.com/2023/01/24/plato-ring-allegory-lord-of-the-rings/

The technology created by Peter Jackson for enabled Paul to decouple ‘s piano from his voice which was the impediment to completing the project.

Source: https://brobible.com/culture/article/beatles-now-and-then-music-video-john-lennon/