In one demonstration, the researchers taped a woman speaking into a camera, and then reprocessed the footage into a new video that showed her speaking entirely new sentences, and even mouthing words to a song in Japanese, a language she does not speak. The results were enough to fool viewers consistently, the researchers report.

The technique's inventors say it could be used in video games and movie special effects, perhaps reanimating Marilyn Monroe or other dead film stars with new lines. It could also improve dubbed movies, a lucrative global industry.