Improving Physics-Augmented Continuum Neural Radiance Field-Based Geometry-Agnostic System Identification with Lagrangian Particle Optimization
- URL: http://arxiv.org/abs/2406.04155v1
- Date: Thu, 6 Jun 2024 15:17:33 GMT
- Title: Improving Physics-Augmented Continuum Neural Radiance Field-Based Geometry-Agnostic System Identification with Lagrangian Particle Optimization
- Authors: Takuhiro Kaneko,
- Abstract summary: Geometry-agnostic system identification is a technique for identifying the geometry and physical properties of an object from video sequences without any geometric assumptions.
Recently, physics-augmented continuum neural radiance fields (PAC-NeRF) has demonstrated promising results for this technique.
We propose Lagrangian particle optimization (LPO), in which the positions and features of particles are optimized through video sequences in Lagrangian space.
- Score: 20.586692311724914
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Geometry-agnostic system identification is a technique for identifying the geometry and physical properties of an object from video sequences without any geometric assumptions. Recently, physics-augmented continuum neural radiance fields (PAC-NeRF) has demonstrated promising results for this technique by utilizing a hybrid Eulerian-Lagrangian representation, in which the geometry is represented by the Eulerian grid representations of NeRF, the physics is described by a material point method (MPM), and they are connected via Lagrangian particles. However, a notable limitation of PAC-NeRF is that its performance is sensitive to the learning of the geometry from the first frames owing to its two-step optimization. First, the grid representations are optimized with the first frames of video sequences, and then the physical properties are optimized through video sequences utilizing the fixed first-frame grid representations. This limitation can be critical when learning of the geometric structure is difficult, for example, in a few-shot (sparse view) setting. To overcome this limitation, we propose Lagrangian particle optimization (LPO), in which the positions and features of particles are optimized through video sequences in Lagrangian space. This method allows for the optimization of the geometric structure across the entire video sequence within the physical constraints imposed by the MPM. The experimental results demonstrate that the LPO is useful for geometric correction and physical identification in sparse-view settings.
Related papers
- Triplet: Triangle Patchlet for Mesh-Based Inverse Rendering and Scene Parameters Approximation [0.0]
inverse rendering seeks to derive the physical properties of a scene, including light, geometry, textures, and materials.
Meshes, as a traditional representation adopted by many simulation pipeline, still show limited influence in radiance field for inverse rendering.
This paper introduces a novel framework called Triangle Patchlet (abbr. Triplet), a mesh-based representation, to comprehensively approximate these parameters.
arXiv Detail & Related papers (2024-10-16T09:59:11Z) - Physics-based reward driven image analysis in microscopy [5.581609660066545]
We present a methodology based on the concept of a Reward Function to optimize image analysis dynamically.
The Reward Function is engineered to closely align with the experimental objectives and broader context.
We extend the reward function approach towards the identification of partially-disordered regions, creating a physics-driven reward function and action space of high-dimensional clustering.
arXiv Detail & Related papers (2024-04-22T12:55:04Z) - Towards Geometric-Photometric Joint Alignment for Facial Mesh
Registration [3.588864037082647]
This paper presents a Geometric-Photometric Joint Alignment method, for accurately aligning human expressions by combining geometry and photometric information.
Experimental results demonstrate faithful alignment under various expressions, surpassing the conventional ICP-based methods and the state-of-the-art deep learning based method.
In practical, our method enhances the efficiency of obtaining topology-consistent face models from multi-view stereo facial scanning.
arXiv Detail & Related papers (2024-03-05T03:39:23Z) - Flexible Isosurface Extraction for Gradient-Based Mesh Optimization [65.76362454554754]
This work considers gradient-based mesh optimization, where we iteratively optimize for a 3D surface mesh by representing it as the isosurface of a scalar field.
We introduce FlexiCubes, an isosurface representation specifically designed for optimizing an unknown mesh with respect to geometric, visual, or even physical objectives.
arXiv Detail & Related papers (2023-08-10T06:40:19Z) - PAC-NeRF: Physics Augmented Continuum Neural Radiance Fields for
Geometry-Agnostic System Identification [64.61198351207752]
Existing approaches to system identification (estimating the physical parameters of an object) from videos assume known object geometries.
In this work, we aim to identify parameters characterizing a physical system from a set of multi-view videos without any assumption on object geometry or topology.
We propose "Physics Augmented Continuum Neural Radiance Fields" (PAC-NeRF), to estimate both the unknown geometry and physical parameters of highly dynamic objects from multi-view videos.
arXiv Detail & Related papers (2023-03-09T18:59:50Z) - PVSeRF: Joint Pixel-, Voxel- and Surface-Aligned Radiance Field for
Single-Image Novel View Synthesis [52.546998369121354]
We present PVSeRF, a learning framework that reconstructs neural radiance fields from single-view RGB images.
We propose to incorporate explicit geometry reasoning and combine it with pixel-aligned features for radiance field prediction.
We show that the introduction of such geometry-aware features helps to achieve a better disentanglement between appearance and geometry.
arXiv Detail & Related papers (2022-02-10T07:39:47Z) - Self-supervised Geometric Perception [96.89966337518854]
Self-supervised geometric perception is a framework to learn a feature descriptor for correspondence matching without any ground-truth geometric model labels.
We show that SGP achieves state-of-the-art performance that is on-par or superior to the supervised oracles trained using ground-truth labels.
arXiv Detail & Related papers (2021-03-04T15:34:43Z) - Fast Gravitational Approach for Rigid Point Set Registration with
Ordinary Differential Equations [79.71184760864507]
This article introduces a new physics-based method for rigid point set alignment called Fast Gravitational Approach (FGA)
In FGA, the source and target point sets are interpreted as rigid particle swarms with masses interacting in a globally multiply-linked manner while moving in a simulated gravitational force field.
We show that the new method class has characteristics not found in previous alignment methods.
arXiv Detail & Related papers (2020-09-28T15:05:39Z) - Convex Geometry and Duality of Over-parameterized Neural Networks [70.15611146583068]
We develop a convex analytic approach to analyze finite width two-layer ReLU networks.
We show that an optimal solution to the regularized training problem can be characterized as extreme points of a convex set.
In higher dimensions, we show that the training problem can be cast as a finite dimensional convex problem with infinitely many constraints.
arXiv Detail & Related papers (2020-02-25T23:05:33Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.