We address the problem of multi-object 3D pose control in image diffusion models. Instead of conditioning on a sequence of text tokens, we propose to use a set of per-object representations, Neural Assets, to control the 3D pose of individual objects in a scene. Neural Assets are obtained by pooling visual representations of objects from a reference image, such as a frame in a video, and are trained to reconstruct the respective objects in a different image, e.g., a later frame in the video. Importantly, we encode object visuals from the reference image while conditioning on object poses from the target frame. This enables learning disentangled appearance and pose features. Combining visual and 3D pose representations in a sequence-of-tokens format allows us to keep the text-to-image architecture of existing models, with Neural Assets in place of text tokens. By fine-tuning a pre-trained text-to-image diffusion model with this information, our approach enables fine-grained 3D pose and placement control of individual objects in a scene. We further demonstrate that Neural Assets can be transferred and recomposed across different scenes. Our model achieves state-of-the-art multi-object editing results on both synthetic 3D scene datasets, as well as two real-world video datasets (Objectron, Waymo Open).
翻译:我们解决了图像扩散模型中的多目标三维姿态控制问题。不同于基于文本标记序列的条件生成,我们提出使用一组针对每个目标的表示——神经资产——来控制场景中各个目标的三维姿态。神经资产通过从参考图像(如视频帧)中池化目标的视觉表示获得,并经过训练以在不同图像(例如视频的后续帧)中重建相应目标。重要的是,我们在编码参考图像中目标视觉信息的同时,以目标帧中的目标姿态作为条件。这使得模型能够学习解耦的外观与姿态特征。将视觉表示与三维姿态表示以标记序列格式结合,使我们能够保持现有模型的文本到图像架构,仅需用神经资产替代文本标记。通过对预训练的文本到图像扩散模型进行基于此信息的微调,我们的方法实现了对场景中单个目标的细粒度三维姿态与位置控制。我们进一步证明神经资产可在不同场景间迁移与重组。该模型在合成三维场景数据集以及两个真实世界视频数据集(Objectron、Waymo Open)上均取得了最先进的多目标编辑效果。