Methods, systems, and apparatus, including medium-encoded computer program products, for providing editable keyframe-based animation data for applying to a character to animate motion of the character in three-dimensional space. Three-dimensional motion data is constructed from two-dimensional videos. The three-dimensional motion data represents movement of people in the two-dimensional videos and includes, for each person, a root of a three-dimensional skeleton of the person. The three-dimensional skeleton comprises multiple three-dimensional poses of the person during at least a portion of frames of a video from the two-dimensional videos. The three-dimensional motion data is converted into editable keyframe-based animation data in three-dimensional space and provided to animate motion.