Face2Face is a fascinating technology that allows realistic facial reenactment in real-time video. Here is a brief overview and review of its key features:

Real-Time Facial Mapping
The core capability of Face2Face is advanced facial mapping and image processing algorithms that can track facial features in one video and transpose those movements onto a face in a separate video in real-time. This facial "puppeteering" works even as the source face moves around.

Facial Expression Transfer
In addition to basic mouth shapes as someone talks, Face2Face can also transfer subtle facial expressions like smiles, frowns, eyebrow raises etc. This helps the reenacted face take on the personality and emotional cues of the driving video for very convincing results.

Retargeting Capabilities
Face2Face allows retargeting a person's facial movements to someone else's face. This means you can make celebrities or friends appear to say things in real-time video by driving their recreated faces with your own live facial movements.

Preserving Original Identity
While the technology manipulates certain facial aspects like expressions, the underlying identity and look of the target face is preserved. Key attributes like skin tone or facial structure remain intact rather than being distorted by the process.

The technology demonstrates the growing sophistication of machine learning for generative synthetic video. Face2Face provides a simple workflow for puppeteering and reenacting faces, allowing even amateur creators to generate compelling video edits. It points to a future where highly-realistic synthetic video becomes increasingly commonplace.