  In this study, our goal is to create interactive avatar agents that can
autonomously plan and animate nuanced facial movements realistically, from both
visual and behavioral perspectives. Given high-level inputs about the
environment and agent profile, our framework harnesses LLMs to produce a series
of detailed text descriptions of the avatar agents' facial motions. These
descriptions are then processed by our task-agnostic driving engine into motion
token sequences, which are subsequently converted into continuous motion
embeddings that are further consumed by our standalone neural-based renderer to
generate the final photorealistic avatar animations. These streamlined
processes allow our framework to adapt to a variety of non-verbal avatar
interactions, both monadic and dyadic. Our extensive study, which includes
experiments on both newly compiled and existing datasets featuring two types of
agents -- one capable of monadic interaction with the environment, and the
other designed for dyadic conversation -- validates the effectiveness and
versatility of our approach. To our knowledge, we advanced a leap step by
combining LLMs and neural rendering for generalized non-verbal prediction and
photo-realistic rendering of avatar agents.
