FF-ProCams: Feed-Forward Gaussian Splatting for Projector-Camera System
FF-ProCams uses feed-forward Gaussian modeling with Mamba2-Transformer to achieve real-time multi-view scene reconstruction in projector-camera systems.
Key Findings
Methodology
FF-ProCams employs a hybrid Mamba2-Transformer encoder to fuse geometric and photometric cues from sparse multi-view observations, predicting relightable 3D Gaussian primitives. It introduces a projector-aware differentiable renderer to simulate arbitrary projection and camera poses. The model is trained end-to-end on a large synthetic dataset covering diverse geometries and materials, enabling fast inference without scene-specific optimization. With only 8 input views, it surpasses traditional optimization-based methods using 297 views, achieving a reconstruction speed of 0.13 seconds, three to five orders of magnitude faster.
Key Results
- FF-ProCams achieves high-fidelity projector-aware rendering, supporting unseen patterns and poses, with a test-time reconstruction time of 0.13 seconds, outperforming optimization-based baselines by a large margin.
- Experimental results on synthetic and real scenes show PSNR improvements of over 5dB, with better generalization to unseen projection patterns and camera configurations.
- Ablation studies confirm the effectiveness of the Mamba2-Transformer for long-range context modeling and the Gaussian representation's adaptability to lighting variations.
Significance
This work addresses the critical bottleneck of slow scene optimization in active projection systems, enabling real-time, high-quality scene reconstruction. It significantly advances spatial augmented reality, projection mapping, and scene reflectance acquisition, bridging the gap between efficiency and accuracy. The method's ability to generalize to unseen patterns and poses opens new avenues for interactive and dynamic projection applications, fostering industrial automation, entertainment, and AR innovations.
Technical Contribution
The paper introduces a novel hybrid encoder combining Mamba2 and Transformer for multi-view feature aggregation, along with a projector-aware differentiable renderer supporting physically-based relighting. It constructs a large synthetic dataset for supervised training, enabling end-to-end learning of relightable Gaussian primitives, which represent scene geometry and reflectance explicitly. This approach departs from prior scene-optimized or baked appearance methods, offering a scalable, fast, and generalizable solution.
Novelty
This is the first framework to perform feed-forward, real-time scene reconstruction for projector-camera systems using relightable Gaussian primitives. It uniquely integrates long-range modeling via Mamba2-Transformer with physically-based rendering, supporting arbitrary projection patterns and dynamic scenes, marking a significant innovation over existing static or scene-optimized methods.
Limitations
- The model struggles with scenes involving highly reflective or complex materials under extreme lighting conditions, leading to residual errors.
- Dependence on pre-calibrated projector and camera parameters limits robustness against calibration inaccuracies.
- Current training relies heavily on synthetic data; real-world domain gaps may affect performance, necessitating domain adaptation techniques.
Future Work
Future research will focus on improving material and lighting modeling robustness, incorporating self-supervised learning to reduce reliance on synthetic data, and extending capabilities to dynamic, non-rigid scenes. Enhancing calibration robustness and exploring unsupervised domain adaptation will further improve practical deployment in real-world environments.
AI Executive Summary
Projector-camera systems (ProCams) are vital for active scene perception and appearance control, widely used in spatial augmented reality and projection mapping. Traditional inverse rendering methods, though high in fidelity, are hampered by lengthy scene-specific optimization, making real-time applications impractical. Meanwhile, mainstream feed-forward 3D reconstruction models lack the ability to adapt to active projection illumination, limiting their effectiveness in dynamic environments. To bridge this gap, the authors propose FF-ProCams, a novel framework that combines a hybrid Mamba2-Transformer encoder with a relightable Gaussian primitive representation. This design enables the model to fuse multi-view geometric and photometric cues efficiently, predicting scene geometry and reflectance in a single forward pass. The introduction of a projector-aware differentiable renderer allows accurate simulation of observations under arbitrary projection patterns and poses, supporting relighting and pose variation without scene optimization. Training on a large synthetic dataset covering diverse geometries and materials, FF-ProCams demonstrates remarkable performance, reconstructing scenes from only 8 views with a speed of 0.13 seconds—over three orders of magnitude faster than traditional methods requiring hours. Experimental results show high fidelity in synthetic and real-world scenarios, with excellent generalization to unseen patterns and configurations. This breakthrough paves the way for real-time, interactive projection systems, significantly impacting AR, entertainment, and industrial applications. Despite these advances, challenges remain in modeling complex materials and handling calibration errors, guiding future research directions toward more robust, adaptive, and dynamic scene understanding solutions.
Deep Analysis
Background
ProCams结合主动投影与被动摄像,近年来在空间增强现实、投影映射等领域得到广泛关注。早期研究多集中在几何校准和光度校正,代表性工作包括利用光传输矩阵(LTM)进行几何匹配,以及基于深度学习的反射场(NeRF)实现高质量场景重建。然而,这些方法多依赖繁琐的场景优化,难以满足实时需求。随着神经渲染和3D表示技术的发展,出现了基于高斯剖分(Gaussian Splatting)和Transformer的端到端模型,显著提升了效率和泛化能力。尽管如此,现有模型多局限于静态场景或固定光照条件,难以应对投影光照变化带来的复杂反射和光照变化问题。
Core Problem
传统ProCams方法依赖场景优化,耗时长(分钟至小时),限制了其在动态交互中的应用。同时,现有前馈模型多只支持被动观察,无法有效模拟投影光照引起的空间变化,导致重建的场景反映光照条件的能力不足。如何在保证高效率的同时,准确建模投影光照变化,成为当前的核心难题。
Innovation
1)提出结合Mamba2-Transformer的混合编码器,有效融合多视角几何与光度信息,提升特征表达能力。2)引入投影器感知的可微渲染器,支持任意投影和相机姿态下的高保真渲染。3)构建大规模合成数据集,提供丰富监督信号,支持端到端训练。4)实现仅用8视角输入,快速重建场景,突破传统优化耗时瓶颈。
Methodology
- �� 输入多视角投影和相机图像,包括黑白场、白色场和投影图像,结合已知相机参数。• 利用混合Mamba2-Transformer编码器,将多视角信息融合成丰富的特征表示。• 通过两个轻量级线性预测头,分别预测几何属性(深度、尺度、旋转、透明度)和材质属性(反照率、粗糙度、环境色)。• 采用光线反投影,将高斯中心沿相机光线回归,确保几何一致性。• 生成高斯原语后,进行投影和光照模拟,利用投影器感知的可微渲染器,模拟复杂投影光照下的观察。• 最终实现端到端训练,优化高斯参数,支持实时推理。
Experiments
- �� 使用合成数据集,涵盖多种几何形状、材质和投影模式,进行训练和验证。• 采用PSNR、MSE等指标评估重建质量,与优化方法(如NeMap)对比。• 进行消融实验验证编码器、渲染器和数据集对性能的贡献。• 在真实场景中测试模型的泛化能力,展示支持未见投影和新姿态的能力。
Results
- �� 仅用8视角,模型在投影感知渲染中达到PSNR提升5dB以上,重建时间缩短至0.13秒,远优于传统方法的几分钟。• 在多场景、多材质条件下,模型表现出优异的泛化能力,误差显著降低。• ablation显示Mamba2-Transformer增强了长距离依赖建模,提升了几何和光照的准确性。
Applications
- �� 适用于空间增强现实、投影映射、场景重建等实时交互场景。• 只需少量视角数据,即可实现快速高质量的场景重建。• 支持复杂投影模式和动态场景,为工业、娱乐等行业提供技术支撑。
Limitations & Outlook
- �� 在极端反射材质或强光条件下,重建误差仍存在。• 依赖预校准参数,实际应用中需考虑校准误差影响。• 目前模型主要在静态场景中验证,动态非刚性场景仍需优化。
Plain Language Accessible to non-experts
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ELI14 Explained like you're 14
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Abstract
Projector-camera (ProCams) systems achieve active scene perception and controllable appearance manipulation via structured illumination, serving as a core infrastructure for spatial augmented reality, projection mapping, and surface reflectance acquisition. Existing inverse-rendering methods for ProCams deliver high-fidelity results but rely on time-consuming per-scene optimization, while mainstream feed-forward 3D reconstruction models produce baked appearance that cannot adapt to spatially varying projector illumination. To resolve this accuracy-efficiency trade-off, we propose FF-ProCams, a Feed-Forward 3D Gaussian inverse-rendering framework for ProCams. A hybrid Mamba2-Transformer encoder aggregates cross-view geometric and photometric cues from sparse multi-view observations, and lightweight heads predict a relightable Gaussian representation in a single forward pass. We further design a projector-aware differentiable renderer to synthesize camera observations under arbitrary active illumination and ProCams poses. To enable feed-forward training, we construct a large-scale synthetic ProCams dataset covering diverse object geometries and surface materials. Experiments show FF-ProCams achieves high-fidelity projector-aware rendering, generalizes to unseen patterns, and supports novel projector-camera poses. Using only 8 input views, it outperforms optimization-based baselines with 297 views while reducing test-time reconstruction to 0.13 seconds (a three-to-five-order-of-magnitude speedup). The code and data are available at https://github.com/CPREgroup/FF-ProCams/.