3DGSR: Implicit Surface Reconstruction with 3D Gaussian Splatting
(2404.00409)Abstract
In this paper, we present an implicit surface reconstruction method with 3D Gaussian Splatting (3DGS), namely 3DGSR, that allows for accurate 3D reconstruction with intricate details while inheriting the high efficiency and rendering quality of 3DGS. The key insight is incorporating an implicit signed distance field (SDF) within 3D Gaussians to enable them to be aligned and jointly optimized. First, we introduce a differentiable SDF-to-opacity transformation function that converts SDF values into corresponding Gaussians' opacities. This function connects the SDF and 3D Gaussians, allowing for unified optimization and enforcing surface constraints on the 3D Gaussians. During learning, optimizing the 3D Gaussians provides supervisory signals for SDF learning, enabling the reconstruction of intricate details. However, this only provides sparse supervisory signals to the SDF at locations occupied by Gaussians, which is insufficient for learning a continuous SDF. Then, to address this limitation, we incorporate volumetric rendering and align the rendered geometric attributes (depth, normal) with those derived from 3D Gaussians. This consistency regularization introduces supervisory signals to locations not covered by discrete 3D Gaussians, effectively eliminating redundant surfaces outside the Gaussian sampling range. Our extensive experimental results demonstrate that our 3DGSR method enables high-quality 3D surface reconstruction while preserving the efficiency and rendering quality of 3DGS. Besides, our method competes favorably with leading surface reconstruction techniques while offering a more efficient learning process and much better rendering qualities. The code will be available at https://github.com/CVMI-Lab/3DGSR.
Overview
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3DGSR is a method that merges implicit SDFs with 3D Gaussian Splatting for detailed 3D surface reconstruction, ensuring high-quality rendering and geometric accuracy.
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The method introduces a differentiable SDF-to-opacity transformation, enabling detailed surface reconstructions by guiding the placement and shape of Gaussians with SDF values.
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It uses volumetric rendering for SDF optimization, employing a consistency regularization to reduce artefacts and improve the overall quality of the reconstructed surface.
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Through extensive evaluations, 3DGSR outperforms existing surface reconstruction techniques, demonstrating its potential in virtual reality, 3D printing, and digital heritage preservation.
3DGSR: Enhanced Surface Reconstruction via Implicit SDF and 3D Gaussian Splatting
Introduction to 3DGSR
The paper introduces 3DGSR, a method that utilizes implicit Signed Distance Fields (SDFs) within a 3D Gaussian Splatting (3DGS) framework to enable detailed and accurate 3D surface reconstruction. This method inherits the efficiency and high-quality rendering capabilities of 3DGS while integrating a novel differentiable SDF-to-opacity conversion, aimed at aligning implicit SDFs with 3D Gaussians for joint optimization. The key contributions include a method for effectively connecting SDF and 3D Gaussians, a strategy to provide dense supervisory signals for continuous SDF learning, and extensive evaluations demonstrating superior performance in both reconstruction quality and rendering efficiency.
Core Components and Methodology
- Differentiable SDF-to-Opacity Transformation: An important innovation in 3DGSR is transforming SDF values into Gaussian opacities, enabling a unified optimization framework that aligns SDFs with 3D Gaussians. This approach allows the SDFs to guide the placement and shape of Gaussians, facilitating detailed surface reconstruction.
- Volumetric Rendering for SDF Optimization: To overcome the sparse supervision provided by optimizing 3D Gaussians alone, 3DGSR incorporates volumetric rendering derived from the SDF. This step introduces consistency regularization, comparing depth and normals rendered from 3D Gaussians against those from the volumetric rendering, effectively optimizing the SDF over the entire space and reducing artefacts in areas not directly covered by Gaussians.
- Experimental Validation: The method is rigorously evaluated against leading surface reconstruction techniques on diverse datasets. The results show that 3DGSR outperforms existing methods in terms of reconstruction quality, as elucidated by a lower Chamfer distance and higher F1 scores, while maintaining competitive rendering performance.
Implications and Future Directions
- Practical Significance: 3DGSR presents a balanced approach to high-quality 3D surface reconstruction and efficient rendering, suitable for applications in virtual reality, 3D printing, and digital heritage preservation where both accurate geometrical details and visual quality are critical.
- Theoretical Contributions: The research addresses the longstanding challenge of integrating SDF-based surface definition with point-based rendering techniques, offering a novel perspective that leverages the strengths of both to achieve superior results.
- Future Research: The paper opens avenues for further exploration into combining implicit geometric representations with other rendering techniques, optimization strategies for the SDF-to-opacity conversion to accommodate varying geometric complexities, and the development of more sophisticated models for handling dynamic scenes.
Conclusion
3DGSR represents a significant advancement in the field of 3D surface reconstruction, providing a method that combines the detailed geometric representation capabilities of implicit SDF with the efficient rendering qualities of 3D Gaussian Splatting. Through its innovative approach to coupling these two components and the comprehensive evaluation against state-of-the-art methods, the paper sets a new benchmark for future research in the domain.