In DreamFusion they do use a NeRF representation.
Nice.
OpenAI shitting their pants even more.
What they don't do is release the actual models and datasets, and it's very expensive to retrain those.
They also release Whisper model and code[2]
btw I like how it hallucinated bumper carrier mounted Spare Wheel based on the size of tires, heavy duty roof rack and bull bars while ground truth render was in a much less likely configuration of stock undercarriage frame hanger/no spare.
On the other hand, diffusion models can learn fairly arbitrary distributions of signals, so by exploiting this learned prior together with view consistency, they can be much more sample efficient than ordinary NeRFs. Without learning such a prior, 3D reconstruction from a single image is extremely ill-posed (much like monocular depth estimation).
Asking as someone who's dreadfully slow at 3d modeling.
https://blogs.nvidia.com/blog/2022/09/23/3d-generative-ai-re...
https://research.nvidia.com/publication/2021-11_extracting-t...