Well, nowadays, as we all know, it is possible. We see its results in movies, video games and other fields of research but not everyone knows how this process works.
The technology that fuses real life and animation and makes it possible to film someone and transfer their data in computerized form is called Motion Capture (also Performance Capture or Mo-cap).
It is somehow a descendant of one animation techniques, Rotoscoping.
Rotoscoping is an animation technique that animators use to track the footage of moving images, frame by frame, to produce realistic action.
Motion capture is used in military, entertainment, sports, medical, and computer vision and robotics validation applications. In film production and video game development, it refers to recording the actions of human actors and using that information to animate digital character models in 2D or 3D computer animation.
It started as a photogrammetric analysis tool in biomechanics research in the 1970s and 1980s and has expanded into other fields as the technology matured.
How does this work? Well, some sensors are needed. Those are placed all over a person to track and record movements, to be converted into data that will create a virtual skeleton in real time.
For example, we have optical systems that use data acquired from image sensors to triangulate the 3D position of a subject between two or more calibrated cameras to provide overlapping projections.
One of the largest motion capture providers in the world is OptiTrack, developed in 1996 by NaturalPoint, Inc. It offers high-performance optical tracking and its product line includes motion capture software and high-speed tracking cameras.
There are many additional accessories, but we may summarize the process like this:
The human body is tracked thanks to markers
identified by camers
then the data is processed in a specific software: Motive.
Here some examples on how does it works:
This system is also used in live performances, to make the human body able to control electronic instruments with its movement.
An example is the composition Bodyscapes from V. Moar, G. Eckel und D. Pirrò:
References
Science World: How Motion Capture works
Wikipedia: Motion Capture
OptiTrack: https://optitrack.com/
Wikipedia: Rotoscoping
