Hybrid Gaussian Splatting for Novel Urban View Synthesis
This work addresses the problem of generating realistic urban views from different traversals for applications like autonomous driving simulation, but it is incremental as it builds on hybrid methods.
The paper tackled novel view synthesis in street scenes by combining Gaussian splatting for 3D reconstruction with a diffusion model for enhancement, achieving an aggregated score of 0.432 and second place in the RealADSim-NVS challenge.
This paper describes the Qualcomm AI Research solution to the RealADSim-NVS challenge, hosted at the RealADSim Workshop at ICCV 2025. The challenge concerns novel view synthesis in street scenes, and participants are required to generate, starting from car-centric frames captured during some training traversals, renders of the same urban environment as viewed from a different traversal (e.g. different street lane or car direction). Our solution is inspired by hybrid methods in scene generation and generative simulators merging gaussian splatting and diffusion models, and it is composed of two stages: First, we fit a 3D reconstruction of the scene and render novel views as seen from the target cameras. Then, we enhance the resulting frames with a dedicated single-step diffusion model. We discuss specific choices made in the initialization of gaussian primitives as well as the finetuning of the enhancer model and its training data curation. We report the performance of our model design and we ablate its components in terms of novel view quality as measured by PSNR, SSIM and LPIPS. On the public leaderboard reporting test results, our proposal reaches an aggregated score of 0.432, achieving the second place overall.