paper-with-me

홈 › Papers

CityDreamer4D: Compositional Generative Model of Unbounded 4D Cities

2025-01-15 · Haozhe Xie, Zhaoxi Chen, Fangzhou Hong, Ziwei Liu

3D scene generation has garnered growing attention in recent years and has made significant progress. Generating 4D cities is more challenging than 3D scenes due to the presence of structurally complex, visually diverse objects like buildings and vehicles, and heightened human sensitivity to distortions in urban environments. To tackle these issues, we propose CityDreamer4D, a compositional generative model specifically tailored for generating unbounded 4D cities. Our main insights are 1) 4D city generation should separate dynamic objects (e.g., vehicles) from static scenes (e.g., buildings and roads), and 2) all objects in the 4D scene should be composed of different types of neural fields for buildings, vehicles, and background stuff. Specifically, we propose Traffic Scenario Generator and Unbounded Layout Generator to produce dynamic traffic scenarios and static city layouts using a highly compact BEV representation. Objects in 4D cities are generated by combining stuff-oriented and instance-oriented neural fields for background stuff, buildings, and vehicles. To suit the distinct characteristics of background stuff and instances, the neural fields employ customized generative hash grids and periodic positional embeddings as scene parameterizations. Furthermore, we offer a comprehensive suite of datasets for city generation, including OSM, GoogleEarth, and CityTopia. The OSM dataset provides a variety of real-world city layouts, while the Google Earth and CityTopia datasets deliver large-scale, high-quality city imagery complete with 3D instance annotations. Leveraging its compositional design, CityDreamer4D supports a range of downstream applications, such as instance editing, city stylization, and urban simulation, while delivering state-of-the-art performance in generating realistic 4D cities.

📄 PDF Abstract BibTeX arXiv:2501.08983

Code (1)

hzxie/CityDreamer4D 공식 구현

Tasks

Scene Generation

Methods 이 논문이 사용한 방법론

Softmax The Softmax output function transforms a previous layer's output into a vector of probabilities. It is commonly used for multiclass classification. Given an input vector $x$…
Attention 설명 없음

Similar Papers 제목 키워드 기반

CityDreamer: Compositional Generative Model of Unbounded 3D Cities

2023-09-01 · CVPR 2024 1 · Haozhe Xie, Zhaoxi Chen, Fangzhou Hong, Ziwei Liu

3D city generation is a desirable yet challenging task, since humans are more sensitive to structural distortions in urban environments. Additionally, generating 3D cities is more complex than 3D natural scenes since bui…

modelScene Generation

GaussianCity: Generative Gaussian Splatting for Unbounded 3D City Generation

2024-06-10 · Haozhe Xie, Zhaoxi Chen, Fangzhou Hong, Ziwei Liu

3D city generation with NeRF-based methods shows promising generation results but is computationally inefficient. Recently 3D Gaussian Splatting (3D-GS) has emerged as a highly efficient alternative for object-level 3D g…

3D GenerationNeRFScene Generation

Generative Gaussian Splatting for Unbounded 3D City Generation

2025-01-01 · CVPR 2025 1 · Haozhe Xie, Zhaoxi Chen, Fangzhou Hong, Ziwei Liu

3D city generation with NeRF-based methods shows promising generation results but is computationally inefficient. Recently 3D Gaussian splatting (3D-GS) has emerged as a highly efficient alternative for object-level …

3D GenerationAttributeDecoderNeRF

Enhancing Multimodal Compositional Reasoning of Visual Language Models with Generative Negative Mining

2023-11-07 · Ugur Sahin, Hang Li, Qadeer Khan, Daniel Cremers 외

Contemporary large-scale visual language models (VLMs) exhibit strong representation capacities, making them ubiquitous for enhancing image and text understanding tasks. They are often trained in a contrastive manner on …

Geometric Signatures of Compositionality Across a Language Model's Lifetime

2024-10-02 · Jin Hwa Lee, Thomas Jiralerspong, Lei Yu, Yoshua Bengio 외

By virtue of linguistic compositionality, few syntactic rules and a finite lexicon can generate an unbounded number of sentences. That is, language, though seemingly high-dimensional, can be explained using relatively fe…