VolumetricSMPL: A Neural Volumetric Body Model for Efficient Interactions, Contacts, and Collisions

TL;DR

VolumetricSMPL achieves 10x faster inference using Neural Blend Weights.

cs.CV 🔴 Advanced 2025-06-29 3 views
Marko Mihajlovic Siwei Zhang Gen Li Kaifeng Zhao Lea Müller Siyu Tang
computer vision body modeling neural networks volumetric model interaction

Key Findings

Methodology

VolumetricSMPL utilizes Neural Blend Weights to generate compact MLP decoders by dynamically blending learned weight matrices using predicted shape- and pose-dependent coefficients, significantly enhancing computational efficiency while maintaining expressiveness.

Key Results

  • VolumetricSMPL achieves a 500x speedup in human-object interaction reconstruction tasks, compared to COAP, with 10x faster inference and 6x lower GPU memory usage.
  • 3x faster and more accurate human mesh recovery in 3D scenes from egocentric views.
  • 7x faster scene-constrained human motion synthesis with 20x lower GPU memory.

Significance

The study significantly improves the efficiency and accuracy of human-environment interaction modeling, addressing computational bottlenecks of traditional mesh models, advancing the field of computer vision.

Technical Contribution

VolumetricSMPL introduces Neural Blend Weights to reduce the size of MLP decoders, offering more efficient computation and memory usage, and supports Signed Distance Function for differentiable contact modeling.

Novelty

This is the first application of Neural Blend Weights in volumetric body modeling, overcoming limitations of traditional large-scale MLP decoders for more efficient inference.

Limitations

  • Complex scenarios may still face self-intersection issues, requiring further optimization.
  • Accuracy of shape and pose predictions depends on the quality of training data.

Future Work

Future research can explore more complex scene interactions, optimize self-intersection handling, and extend to more human motion synthesis tasks.

AI Executive Summary

VolumetricSMPL is a novel neural volumetric body model that enables efficient interactions, contacts, and collisions through Neural Blend Weights. Traditional mesh models face computational bottlenecks in handling complex interactions, while VolumetricSMPL significantly improves inference speed and memory efficiency by dynamically blending weight matrices.

Experimental results demonstrate the model's superior performance across multiple tasks, including human-object interaction reconstruction, human mesh recovery in 3D scenes, and scene-constrained human motion synthesis. Compared to previous models like COAP, VolumetricSMPL achieves 10x faster inference and 6x lower GPU memory usage.

Despite these advancements, VolumetricSMPL may still encounter self-intersection issues in complex scenarios. Future research can further optimize self-intersection handling and extend to more human motion synthesis tasks. The model's broad applicability and significant performance improvements offer new possibilities in the field of computer vision.

Deep Analysis

Background

Body modeling plays a crucial role in computer vision and graphics. Traditional mesh models face computational bottlenecks in handling human-environment interactions. Recently, volumetric neural implicit models have gained attention, but they come with high computational costs and memory requirements.

Core Problem

Traditional mesh models are inefficient in handling complex human articulations and interactions, making efficient contact and collision detection challenging, thus limiting their application scope.

Innovation

VolumetricSMPL achieves compact MLP decoders through Neural Blend Weights, dynamically blending weight matrices, significantly enhancing computational efficiency while maintaining expressiveness.

Methodology

  • �� Use Neural Blend Weights to generate compact MLP decoders.

  • �� Dynamically blend weight matrices using predicted shape- and pose-dependent coefficients.

  • �� Implement Signed Distance Function for efficient and differentiable contact modeling.

Experiments

Experiments were conducted using multiple datasets, evaluating tasks such as human-object interaction reconstruction and human mesh recovery in 3D scenes. Compared to COAP, significant improvements in speed and memory usage were demonstrated.

Results

Achieved 500x speedup in human-object interaction reconstruction, with improved accuracy. 3x faster human mesh recovery in 3D scenes, and 7x faster scene-constrained human motion synthesis.

Applications

The model can be used for real-time human motion capture, interaction modeling in virtual reality, and human motion synthesis in complex scenes.

Limitations & Outlook

Complex scenarios may face self-intersection issues, requiring further optimization. Accuracy of shape and pose predictions depends on the quality of training data.

Plain Language Accessible to non-experts

Imagine you're in a kitchen cooking, and VolumetricSMPL is like a smart chef assistant. Traditional mesh models are like manually chopping vegetables, inefficient, while VolumetricSMPL, through Neural Blend Weights, is like an automatic vegetable chopper, quickly and efficiently handling various ingredients. It can automatically adjust chopping styles based on different dish requirements, ensuring every dish is perfect.

ELI14 Explained like you're 14

Hey there! Imagine playing a game where the character and environment interactions are as real as in the real world. VolumetricSMPL is like a super-smart game engine that quickly processes character movements and environmental changes. It's like a magician, allowing your game character to move freely in complex scenes without lag or errors. Isn't that cool?

Glossary

Neural Blend Weights

A method for dynamically blending weight matrices to generate compact MLP decoders.

Used in VolumetricSMPL to enhance computational efficiency.

Signed Distance Function

A function representing the distance to an object's surface, supporting differentiable contact modeling.

Implemented in VolumetricSMPL for contact modeling.

MLP Decoder

A multi-layer perceptron used for decoding input data.

Used in VolumetricSMPL to generate volumetric models.

COAP

A volumetric occupancy model using large-scale MLP decoders.

Compared with VolumetricSMPL for performance analysis.

Human-Object Interaction

Study of interaction behaviors between humans and objects.

VolumetricSMPL used for reconstructing such interactions.

Open Questions Unanswered questions from this research

  • 1 How to further optimize self-intersection handling in complex scenarios?
  • 2 How to improve the accuracy of shape and pose predictions?

Applications

Immediate Applications

Real-time motion capture

Achieve efficient motion capture using VolumetricSMPL, applicable in virtual reality and film production.

Long-term Vision

Intelligent interaction systems

Future development of smarter interaction systems for natural human-environment interaction.

Abstract

Parametric human body models play a crucial role in computer graphics and vision, enabling applications ranging from human motion analysis to understanding human-environment interactions. Traditionally, these models use surface meshes, which pose challenges in efficiently handling interactions with other geometric entities, such as objects and scenes, typically represented as meshes or point clouds. To address this limitation, recent research has explored volumetric neural implicit body models. However, existing works are either insufficiently robust for complex human articulations or impose high computational and memory costs, limiting their widespread use. To this end, we introduce VolumetricSMPL, a neural volumetric body model that leverages Neural Blend Weights (NBW) to generate compact, yet efficient MLP decoders. Unlike prior approaches that rely on large MLPs, NBW dynamically blends a small set of learned weight matrices using predicted shape- and pose-dependent coefficients, significantly improving computational efficiency while preserving expressiveness. VolumetricSMPL outperforms prior volumetric occupancy model COAP with 10x faster inference, 6x lower GPU memory usage, enhanced accuracy, and a Signed Distance Function (SDF) for efficient and differentiable contact modeling. We demonstrate VolumetricSMPL's strengths across four challenging tasks: (1) reconstructing human-object interactions from in-the-wild images, (2) recovering human meshes in 3D scenes from egocentric views, (3) scene-constrained motion synthesis, and (4) resolving self-intersections. Our results highlight its broad applicability and significant performance and efficiency gains.

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