🤖 AI Summary
This study investigates the structural properties and predictability limits of convergence solutions in multi-view optimization with 3D Gaussian Splatting (3DGS), focusing on how density distribution influences the coupling between geometry and appearance parameters. Through statistical analysis, learnability probing, and variance decomposition, the work reveals for the first time that rendering-optimal references (RORs) exhibit bimodal scale and radiance characteristics. A density-stratification mechanism is introduced to distinguish geometry-dominated regions from view-synthesis-dominated ones. Building on this insight, a rendering-free, density-aware predictor is developed, demonstrating that parameters in high-density regions can be accurately predicted from point clouds, whereas sparse regions suffer prediction failure due to strong parameter coupling. The proposed strategy substantially enhances training robustness.
📝 Abstract
We investigate what structure emerges in 3D Gaussian Splatting (3DGS) solutions from standard multi-view optimization. We term these Rendering-Optimal References (RORs) and analyze their statistical properties, revealing stable patterns: mixture-structured scales and bimodal radiance across diverse scenes. To understand what determines these parameters, we apply learnability probes by training predictors to reconstruct RORs from point clouds without rendering supervision. Our analysis uncovers fundamental density-stratification. Dense regions exhibit geometry-correlated parameters amenable to render-free prediction, while sparse regions show systematic failure across architectures. We formalize this through variance decomposition, demonstrating that visibility heterogeneity creates covariance-dominated coupling between geometric and appearance parameters in sparse regions. This reveals the dual character of RORs: geometric primitives where point clouds suffice, and view synthesis primitives where multi-view constraints are essential. We provide density-aware strategies that improve training robustness and discuss architectural implications for systems that adaptively balance feed-forward prediction and rendering-based refinement.