  In this paper we describe a learned method of traffic scene generation
designed to simulate the output of the perception system of a self-driving car.
In our "Scene Diffusion" system, inspired by latent diffusion, we use a novel
combination of diffusion and object detection to directly create realistic and
physically plausible arrangements of discrete bounding boxes for agents. We
show that our scene generation model is able to adapt to different regions in
the US, producing scenarios that capture the intricacies of each region.
