  Existing 3D-aware portrait synthesis methods can generate impressive
high-quality images while preserving strong 3D consistency. However, most of
them cannot support the fine-grained part-level control over synthesized
images. Conversely, some GAN-based 2D portrait synthesis methods can achieve
clear disentanglement of facial regions, but they cannot preserve view
consistency due to a lack of 3D modeling abilities. To address these issues, we
propose 3D-SSGAN, a novel framework for 3D-aware compositional portrait image
synthesis. First, a simple yet effective depth-guided 2D-to-3D lifting module
maps the generated 2D part features and semantics to 3D. Then, a volume
renderer with a novel 3D-aware semantic mask renderer is utilized to produce
the composed face features and corresponding masks. The whole framework is
trained end-to-end by discriminating between real and synthesized 2D images and
their semantic masks. Quantitative and qualitative evaluations demonstrate the
superiority of 3D-SSGAN in controllable part-level synthesis while preserving
3D view consistency.
