在 3D 视觉领域， 如何从二维图像快速、精准地恢复三维世界 ，一直是计算机视觉与计 算 机 图 形 学 最 核 心 的 问 题 之 一 。 从 早 期 的 Structure-from-Motion (SfM) 到 Neural Radiance Fields (NeRF) ，再到 3D Gaussian Splatting (3DGS) ，技术的演进让我们 离实时、通用的 3D 理解越来越近。然而，以往的方法往往依赖于每个场景的反复优化 （per-scene optimization），既慢又缺乏泛化能力。在 AI 驱动的新时代，一个全新的范 式正在崛起 —— Feed-Forward 3D 。 点击下方 卡片 ，关注" 3D视觉之心 "公众号 第一时间获取 3D视觉干货 论文标题：Advances in Feed-Forward 3D Reconstruction and View Synthesis: A Survey 论文链接：https://arxiv.org/abs/2507.14501 论文主页：https://fnzhan.com/projects/Feed-Forward-3D/ 这篇由 ...

Core Viewpoint - The article discusses advancements in autonomous driving simulation technology, highlighting the integration of various components such as scene rendering, data collection, and intelligent agents to create realistic driving environments [1][2][3]. Group 1: Simulation Components - The first step involves creating a static environment using 3D Gaussian Splatting and Diffusion Models to build a realistic cityscape, capturing intricate details [1]. - The second step focuses on data collection from panoramic views to extract dynamic assets like vehicles and pedestrians, enhancing the realism of simulations [2]. - The third step emphasizes relighting techniques to ensure that assets appear natural under various lighting conditions, simulating different times of day and weather scenarios [2]. Group 2: Intelligent Agents and Weather Systems - The fourth step introduces intelligent agents that mimic real-world behaviors, allowing for complex interactions within the simulation [3]. - The fifth step incorporates weather systems to enhance the atmospheric realism of the simulation, enabling scenarios like rain or fog [4]. Group 3: Advanced Features - The sixth step includes advanced features that challenge autonomous vehicles with unexpected obstacles, simulating real-world driving complexities [4].

Core Viewpoint - The article discusses the development and implementation of the Street Gaussians algorithm, which aims to efficiently model dynamic street scenes for autonomous driving simulations, addressing previous limitations in training and rendering speeds [2][3]. Group 1: Background and Challenges - Previous methods faced challenges such as slow training and rendering speeds, as well as inaccuracies in vehicle pose tracking [3]. - The Street Gaussians algorithm represents dynamic urban street scenes as a combination of point-based backgrounds and foreground objects, utilizing optimized vehicle tracking poses [3][4]. Group 2: Technical Implementation - The background model is represented as a set of points in world coordinates, each assigned a 3D Gaussian to depict geometric shape and color, with parameters including covariance matrices and position vectors [8]. - The object model for moving vehicles includes a set of optimizable tracking poses and point clouds, with similar Gaussian attributes to the background model but defined in local coordinates [11]. Group 3: Innovations in Appearance Modeling - The article introduces a 4D spherical harmonic model to encode temporal information into the appearance of moving vehicles, reducing storage costs compared to traditional methods [12]. - The effectiveness of the 4D spherical harmonic model is demonstrated, showing significant improvements in rendering results and reducing artifacts [16]. Group 4: Initialization Techniques - Street Gaussians utilizes aggregated LiDAR point clouds for initialization, addressing the limitations of traditional SfM point clouds in urban environments [17]. Group 5: Course and Learning Opportunities - The article promotes a specialized course on 3D Gaussian Splatting (3DGS), covering various subfields and practical applications in autonomous driving, aimed at enhancing understanding and implementation skills [26][30].

Core Viewpoint - The emergence of 3D Gaussian Splatting (3DGS) as a leading 3D modeling technology has introduced significant security vulnerabilities, particularly through a newly proposed attack method called Poison-Splat, which can drastically increase training costs and system failures [1][2][31]. Group 1: Introduction and Background - 3DGS has rapidly become a dominant technology in 3D vision, replacing NeRF due to its high rendering efficiency and realism [2][7]. - The adaptive nature of 3DGS, which adjusts computational resources based on scene complexity, is both a strength and a potential vulnerability [8][11]. - The research highlights a critical security blind spot in mainstream 3D reconstruction systems, revealing how minor alterations to input images can lead to significant operational disruptions [2][31]. Group 2: Attack Mechanism - The Poison-Splat attack targets the GPU memory usage and training time by introducing perturbations to input images, leading to increased computational costs [12][22]. - The attack is modeled as a max-min bi-level optimization problem, employing innovative strategies such as a proxy model to approximate the victim's behavior and maximizing the Total Variation (TV) of images to induce excessive complexity in 3DGS [13][16][15]. - The attack can significantly increase GPU memory usage from under 4GB to 80GB and training time by up to five times, demonstrating its effectiveness [25][22]. Group 3: Experimental Results - Experiments conducted on various 3D datasets showed that unconstrained attacks could lead to GPU memory usage surging by 20 times and rendering speeds dropping to one-tenth of the original [25][22]. - Even with constraints on pixel perturbations, the attack remains potent, with some scenarios showing over eightfold increases in memory consumption [27][22]. Group 4: Implications and Contributions - The research emphasizes that the findings are not merely academic but represent real threats to 3D service providers that allow user-uploaded content [31][40]. - Simple defenses, such as limiting the number of Gaussian points, are ineffective as they compromise the quality of 3D reconstructions [39][35]. - The study aims to raise awareness about the security of AI systems in 3D modeling, advocating for the development of more intelligent defense mechanisms [41][37].