Motion Capture in Computer Graphics

Today, we see many movies, games, animations, 2D and 3D images, and drug designing. Have you ever wondered how these things have been created and how they work? These projections replicate the same of living beings and creatures. This could done with Computer Graphics.

What is Computer Graphics?

Computer Graphics is a term that refers to the creation and manipulation such as any sketch or image from the computer for a meaningful representation. Computer graphics techniques are used in many fields like animation, rendering 2D and 3D images, graphical user interface (UI) designs, to make stimulation and other games, movies and film making industries and many more. Another term coined for computer graphics is ‘CG’ or ‘CGI’.

The term ‘Computer Graphics’ was given by Verne Hudson and William Fetter who were from Boeing.

Types of Computer Graphics

There are mainly two broad categories:

• Raster Graphics
• Vector Graphics

1. Raster Graphics

Another term used for ‘RG’ is ‘Bitmap images’. These are the graphics composed of pixel grids. Here each pixel has its specific color value and is used for drawing an image web graphics and digital photography. Extensions used: SVG, EPS, PDF, AI, DXF.

A Raster Graphic designed image

2. Vector Graphics

The graphics are designed using mathematical equations or geometrical shapes to create shapes, lines, etc. They carry the advantage of scaled infinitely without losing quality.

Extensions used: .BMP, .TIF, .GIF, .JPG.

A Vector Graphic designed image

Computer Graphics have rendering, modelling, and animation fundamentals known as projections. From this, the computer can render 3D scenes to 2D images.

Segments in Computer Graphics

Segments are basic building blocks of a graphical scene. They are commonly used in 2D graphics to represent lines or curves that connect two or more points.

Types of Segments :

• Posted Segment: When the visible attribute of the segment is set to 1, it is called a Posted segment. This is included in the active segment list.
• Unposted Segment: When a visible attribute of the segment is set to 0, it is called an Unposted segment. This is not included in the active segment list.

Applications

• Used in pharmaceutical sciences for drug formulation using Computer-aided drug design.
• Rapidly growing in animation for creating different models and characters.
• A well-used to generate 3D Graphics.
• To produce a skilled and detailed virtual reality environment.

What is Motion Capture?

Motion capture is the technique used to digitally record the movement of objects or people for various purposes like education through virtual reality, making games, movies, etc.

Motion capture allows one to make a highly realistic virtual environment, as it captures the subtle nuances and details of human or object motion that would be difficult to replicate manually.

Types of Motion Capture

There are 2 types of motion capture, they are:

1. Optical Motion Capture

• Active Optical Motion Capture: These systems use markers with built-in light sources. The light is infrared which is captured by the specialized camera and offers a better accuracy in motion tracking.
• Passive Optical motion capture: Here, reflective markers are used at the object or subject. Multiple cameras capture the subject in 3 Dimensions allowing better motion tracking.

2. Inertial Motion Capture

This method does not use cameras and markers instead gyroscopes and accelerometers are attached to the subject body. They detect the movement. This method is used in outdoor scenarios where cameras are impractical.

What Does Motion Capture do in Computer Graphics?

The motion capture captures the real human effects and the very minute detail of every fraction of the body movement. It gives:

• The Motion Capture technique helps the creators to observe movements and actual actors’ details, which is then used to create virtual reality concepts. This makes the animation look more realistic.
• This technique helps in saving time by easily, rapidly, and accurately tracking motions and gestures. This gives an edge in the resource-saving process, allowing for faster production of high-quality animations.
• It doesn’t only permit recording the movements, but also the gestures, detailed expressions and motions. This adds richness and expressiveness to the visuals of animation, making them more interesting and realistic.
• By using motion capture data, animators can ensure consistency in movement throughout a scene or project.

Applications of Motion Graphics

• Data capture: capturing the real-life movement of human beings and apply to give more edge and depth in animation and movies.
• Animation: motion capture allows to making of realistic character movements and replicating real-life aspects.
• Data Processing: The captured data is processed to extract the motion information. This involves tracking the movement of the markers in 3D space and converting it into a digital representation of the movement.

Conclusion

We have discussed computer graphics and its fundamentals, motion capture, their types, how they work and their proper application.

Frequently Asked Questions on Motion Capture – FAQs

Define motion capture.

Motion capture is a technique used to create animations and VRs by tracking the real-life motions and gestures of human beings and other living beings.

What software is commonly used for motion capture data processing?

i) MotionBuilder

ii) Blender

iii) Vicon Nexus

iv) Rokoko Studio

v) OptiTrack Motive

What is the role of motion capture in sports analysis and biomechanical research?

The motion capture plays a vital role in sports and biomechanical research to reduce injury chances and to teach correct techniques to the players.

How does the motion capture technology act?

Motion capture technique allows the user to record the real-time gestures, minor details of expressions and movements of the living beings, then the data gathered is processed and calibrated and when required the data is integrated with animated characters and visuals.