Optical flow-based tracking

In January 2020, it was announced that The Irishman, a movie directed by Martin Scorsese, was nominated for an Oscar. This movie details the life of truck driver, gangster, and teamster Frank Sheeran (played by Robert DeNiro). In the movie, we see Sheeran at different times in his life. From the time he was in his 20's to the time he was in his 80's. The whole time we saw DeNiro on the screen it was obvious that it was him and you could really tell that he was twenty years old or eighty years old.

In previous movies, this might have been achieved with makeup. For this movie, makeup was not used for this purpose. Instead they used special effects and they retouched DeNiro's face with digital makeup. Amazing, right?

For many years, making realistic faces with computers was extremely difficult, but Hollywood and its special effects artists have finally cracked the code. Obviously, they are using more sophisticated techniques...