AA-Splat: Anti-Aliased Feed-forward 3D Gaussian Splatting

다국어 초록 (Multilingual Abstract)

Feed-forward 3D Gaussian Splatting (FF-3DGS) methods are promising in 3D reconstruction and novel view synthesis (NVS), for their ability to reliably reconstruct sparse-view scenes without the need for costly per-scene optimization. However, FF-3DGS methods continue to be built using incorrect screen-space dilation filters, which result in severe aliasing and erosion artifacts when rendering sampling rates are drastically altered from those seen during training (i.e., rendering at drastically zoomed-in/out views). We observe that merely integrating the 2D Mip filters and 3D band-limiting used for anti-aliased per-scene 3DGS into FF-3DGS causes unnatural grid-like rendering artifacts due to interfering with the pixel-aligned nature of the primitives. We adopt an opacity balancing (OB) technique to seamlessly integrate overlapping pixel-aligned Gaussian primitives into the rendering process. We observe that OB compensation is complementary with the 2D Mip filter and 3D band-limiting filters, where removal of either reintroduces unnatural rendering artifacts for zoomed-in views. We test AA-Splat on multi-scale extensions of common FF-3DGS benchmarks and demonstrate massive improvements on out-of-distribution scales.