If developing video games or cartoons is your favourite occupation, then we are sure that you have seen the following cliché. This is a man in a black tight suit, covered in sensors from head to toe. From the outside, they look ridiculous, but we are sure that these curious subjects perform important work in real life. These people may be world-famous actors, but now we’re going to tell you a secret that these are just talented actors who play motion-capture animations. Through their actions, 3D models can realistically move and have live facial expressions.
How motion capture technology works
The work of an actor who plays in motion capture scenes is much more complicated than it seems at first sight. The costume of such an actor has some special sensors that the camera scans. Then, this program processes the actions of a living person and creates a model using frames. Within this model, the frame is made of hinges for its sliding. Such frames are the best option for any animated 3D model. There are two general types of motion capture:
- An optical passive system in which infrared light is transmitted to the sensors, that is, the markers and it is reflected from them, then comes into the lenses of the cameras again. After that, the software calculates the position of the sensors in space.
- Optical active system, in which markers have a replacement in the form of LEDs, each of which has its own name. According to this name, this program recognizes the position of the LED in the space and connects it with the required dice on the model. Thanks to individual names, there is almost no confusion in this system.
In the modern world, there is one more motion capture system such as magnetic. Within this model, the markers are positioned by magnetic flow distortion. There are also gyroscopic circuits that send data directly to the computer. A few years ago, experts found a problem in these systems, such as difficulties in working. For example, magnetic systems cannot work reliably due to the presence of fittings and wiring at the base of the room. Gyroscopic circuits require a large number of wires.
Features of the modern system
Modern motion capture technology has components that meet the requirements of any such system. Actors’ faces also have special sensors that they attach to their faces. Now, they look neater and smaller. So, there are more than 80-220 units of these. Each actor has a bezel in front of his face, which includes a camera that records the actor’s facial expressions in real time. The sensors on the suit inform the camera of the movement of the human body. Modern game engines can independently complete the movements of the actor, and thus they improve the acting. This feature is useful if the marker has been lost from sight. They create a clear image before filming is finished. However, this is not the last step in the process as there is some refinement of the inaccuracies as well as the addition of new moves. All these procedures are performed manually.
How do mockup actors work?
There are some actors who do mockup acting. Such actors must play joyful and sad situations on the set in front of a large number of outsiders )we mean pavilion workers). In this process, a large number of sensors are on each actor, and they can hold different items in their hands. When shooting a certain object in close-up, the camera should film only the movement of fingers and hands. Furniture, doors and motorcycles are fake items that specialists and artists create from plywood, cardboard or plastic. These items must be as compact as possible, or even transparent, so that the movement of markers does not overlap with them. In order for the sensors on the actors’ costumes to work reliably, on the set, the props must be matt and do not reflect artificial or natural light.
Sometimes, mockup is a tool for working with animal actors too. So, Red Dead Redemption is a game for which its creators created to capture the movements of horses that had to move as naturally as possible. During the filming of key scenes, this horse often dropped the sensors, and the crew were forced to re-shoot many duplicates. This horse was also the source of the horses within this game. Sometimes, dogs and other animals were also used by actors to capture movement. Thus, this technology has had a huge impact on the creation of video games and animations and made them more realistic.
