Unsigned Distance Fields (UDFs) are a natural implicit representation for open surfaces but, unlike Signed Distance Fields (SDFs), are challenging to triangulate into explicit meshes. This is especially true at high resolutions where neural UDFs exhibit higher noise levels, which makes it hard to capture fine details. Most current techniques perform within single voxels without reference to their neighborhood, resulting in missing surface and holes where the UDF is ambiguous or noisy. We show that this can be remedied by performing several passes and by reasoning on previously extracted surface elements to incorporate neighborhood information. Our key contribution is an iterative neural network that does this and progressively improves surface recovery within each voxel by spatially propagating information from increasingly distant neighbors. Unlike single-pass methods, our approach integrates newly detected surfaces, distance values, and gradients across multiple iterations, effectively correcting errors and stabilizing extraction in challenging regions. Experiments on diverse 3D models demonstrate that our method produces significantly more accurate and complete meshes than existing approaches, particularly for complex geometries, enabling UDF surface extraction at higher resolutions where traditional methods fail.
翻译:无符号距离场(UDFs)是开放曲面的自然隐式表示,但与有符号距离场(SDFs)不同,将其三角化为显式网格具有挑战性。这在神经UDFs表现出更高噪声水平的高分辨率情况下尤为明显,导致难以捕捉精细细节。现有技术大多在单个体素内独立处理,未参考邻域信息,导致在UDF模糊或噪声区域出现表面缺失和孔洞。我们证明,通过多次迭代处理并基于先前提取的表面元素进行邻域信息推理,可有效解决此问题。我们的核心贡献在于提出一种迭代神经网络,通过空间传播来自渐远邻域的信息,逐步提升每个体素内的表面重建质量。与单次处理方法不同,我们的方法在多次迭代中整合新检测的表面、距离值和梯度,有效修正错误并稳定挑战性区域的提取。在多样化三维模型上的实验表明,本方法生成的网格比现有方法显著更精确完整,尤其适用于复杂几何结构,实现了传统方法无法达成的高分辨率UDF表面提取。