NTR-Gaussian: Nighttime Dynamic Thermal Reconstruction with 4D Gaussian Splatting Based on Thermodynamics

Thermal infrared imaging enables a non-invasive measurement of the surface temperature of objects with all-weather applicability. Leveraging such techniques for 3D reconstruction can accurately reflect the temperature distribution of a scene, thereby supporting applications such as building monitoring and energy management. However, existing approaches predominantly focus on static 3D reconstruction for a single time period, overlooking the dynamic nature of thermal radiation phenomena, and failing to predict or analyze temperature variations over time. In this paper, we introduce a novel method, termed NTR-Gaussian, grounded in thermodynamics to address the challenge of nighttime dynamic thermal reconstruction using 4D Gaussian Splatting. Specifically, We utilize neural networks to predict thermodynamic parameters, such as emissivity, convective heat transfer coefficient, and heat capacity, etc. By means of integration, we numerically solve the infrared temperature of the scene at each moment during the night, so as to predict the temperature of the nighttime scene more accurately. To further advance research in this domain, we release a comprehensive dataset of dynamic thermal reconstruction spanning four distinct regions. Extensive experiments demonstrate that NTR-Gaussian significantly outperforms comparison methods in thermal reconstruction, achieving a predicted temperature error within 1 degree Celsius. The code is available at https://github.com/NPUCVPG/NTR-Gaussian.