Traditionally, all 3D animation had been done with keyframe animation. This means that an animator must move the character for each frame, which can add up to hundreds of thousands of frames for a single project. It’s an incredibly complex and tedious process. 

Motion capture provides data that realistically portrays how the body naturally moves. The animator will then review the raw data, fix any errors, and tweak the motions to match how they want the character to move. This process is called clean up animation.