  Live animation of 2D characters has recently become a popular way for
storytelling, and has potential application scenarios like tele-present agents
or robots. As an extension of human-human communication, there is a need for
augmenting the emotional communication experience of live animation. In this
paper, we explore the emotional expressiveness issue of 2D live animation. In
particular, we propose a descriptive emotion command model to bind a triggering
action, the semantic meaning, psychology measurements, and behaviors of an
emotional expression. Based on the model, we designed and implemented a
proof-of-concept 2D live animation system, where a novel visual programming
tool for editing the behaviors of 2D digital characters, and an emotion command
recommendation algorithm are proposed. Through a user evaluation, we showcase
the usability of our system and its potential for boosting creativity and
enhancing the emotional communication experience.
