We introduce 3D Gaussian blendshapes for modeling photorealistic head avatars. Taking a monocular video as input, we learn a base head model of neutral expression, along with a group of expression blendshapes, each of which corresponds to a basis expression in classical parametric face models. Both the neutral model and expression blendshapes are represented as 3D Gaussians, which contain a few properties to depict the avatar appearance. The avatar model of an arbitrary expression can be effectively generated by combining the neutral model and expression blendshapes through linear blending of Gaussians with the expression coefficients. High-fidelity head avatar animations can be synthesized in real time using Gaussian splatting. Compared to state-of-the-art methods, our Gaussian blendshape representation better captures high-frequency details exhibited in input video, and achieves superior rendering performance.
我们引入了3D高斯混合形状（blendshapes）来模拟逼真的头部头像。输入单眼视频，我们学习了一个中性表情的基础头部模型，以及一组表情混合形状，每一个都对应于经典参数面部模型中的基础表情。中性模型和表情混合形状均以3D高斯表示，这些高斯包含几个属性以描述头像外观。通过将中性模型和表情混合形状通过高斯线性混合与表情系数结合，可以有效地生成任意表情的头像模型。使用高斯喷溅技术可以实时合成高保真的头部头像动画。与最先进的方法相比，我们的高斯混合形状表示更好地捕捉了输入视频中展示的高频细节，并实现了更优越的渲染性能。