  Talking head video generation aims to produce a synthetic human face video
that contains the identity and pose information respectively from a given
source image and a driving video.Existing works for this task heavily rely on
2D representations (e.g. appearance and motion) learned from the input images.
However, dense 3D facial geometry (e.g. pixel-wise depth) is extremely
important for this task as it is particularly beneficial for us to essentially
generate accurate 3D face structures and distinguish noisy information from the
possibly cluttered background. Nevertheless, dense 3D geometry annotations are
prohibitively costly for videos and are typically not available for this video
generation task. In this paper, we first introduce a self-supervised geometry
learning method to automatically recover the dense 3D geometry (i.e.depth) from
the face videos without the requirement of any expensive 3D annotation data.
Based on the learned dense depth maps, we further propose to leverage them to
estimate sparse facial keypoints that capture the critical movement of the
human head. In a more dense way, the depth is also utilized to learn 3D-aware
cross-modal (i.e. appearance and depth) attention to guide the generation of
motion fields for warping source image representations. All these contributions
compose a novel depth-aware generative adversarial network (DaGAN) for talking
head generation. Extensive experiments conducted demonstrate that our proposed
method can generate highly realistic faces, and achieve significant results on
the unseen human faces.
