Author Login Chief Editor Login Reviewer Login Editor Login Remote Office

Computer Engineering ›› 2025, Vol. 51 ›› Issue (8): 95-106. doi: 10.19678/j.issn.1000-3428.0069317

• Research Hotspots and Reviews • Previous Articles     Next Articles

Acceleration Approach for Neural Radiance Field in Dynamic 3D Human Reconstruction

XIAO Yilong1, DENG Yiqin2, CHEN Zhigang1,*()   

  1. 1. School of Computer Science and Engineering, Central South University, Changsha 410083, Hunan, China
    2. School of Control Science and Engineering, Shandong University, Jinan 250061, Shandong, China
  • Received:2024-01-29 Revised:2024-04-10 Online:2025-08-15 Published:2025-08-15
  • Contact: CHEN Zhigang

面向动态三维人体重建的神经辐射场加速方法

肖祎龙1, 邓伊琴2, 陈志刚1,*()   

  1. 1. 中南大学计算机学院, 湖南 长沙 410083
    2. 山东大学控制科学与工程学院, 山东 济南 250061
  • 通讯作者: 陈志刚
  • 基金资助:
    2020年度科技创新2030—“新一代人工智能”重大项目(2020AAA0109605); 国家自然科学基金(62301300); 中国博士后自然科学基金(2023M732090); 长沙市科技计划重大专项(kh2103016); 山东省自然科学基金(ZR2023QF053)

Abstract:

This study proposes a novel acceleration method for the Neural Radiance Field (NeRF) in dynamic 3D human reconstruction to address the challenges of low training efficiency and high computational complexity in volume rendering. To improve the ability of the NeRF to represent detailed local features, multiresolution hash encoding is used as positional encoding, which increases the NeRF′s convergence speed. In addition, a shallow network is designed to estimate the volume density of the NeRF. An opacity loss function is proposed to optimize the network using the human alpha map output obtained by PP-Matting. The proposed density estimation network is used to compute the transmittance distribution along the camera rays during volume rendering. The importance sampling strategy for volume rendering is then implemented by inversely sampling the transmittance distribution, which reduces the number of unnecessary sampling points and improves the volume rendering′s computational efficiency. Furthermore, precise human foreground masks are generated by binarizing human alpha maps, which enhances the quality of the reconstructed datasets. Extensive experiments demonstrate that the combination of multiresolution hash encoding and importance sampling strategy improves the reconstruction speed on the ZJU-MoCap and SHTU-MoCap datasets by 17.7%, 9.5%, and 37.5%, respectively, compared to the Neural Body, HumanNeRF, and MonoHuman, while also achieving higher reconstruction accuracy. The use of binarized PP-Matting increases the accuracy of human masks to over 96%.

Key words: 3D human reconstruction, Neural Radiance Field (NeRF), volume rendering acceleration, human mask extraction, positional encoding

摘要:

针对动态三维人体重建场景下神经辐射场训练效率低和体渲染计算复杂度高的问题,提出一种神经辐射场(NeRF)加速方法。引入多分辨率哈希编码作为位置特征编码,提高神经辐射场的局部细节特征表示能力,加快模型收敛;设计体密度估计网络,添加不透明度损失函数,结合PP-Matting方法输出的人体透明度图优化体密度估计网络,通过估计体渲染过程中相机射线上透射率分布,结合逆变换采样实现体渲染重要性采样,减少无效采样点,提高体渲染计算效率;通过二值化透明度图获得高精度人体前景掩码,提高人体重建数据集质量。实验结果表明,引入多分辨率哈希编码和体渲染重要性采样策略后,该方法在ZJU-MoCap和SHTU-MoCap数据集上重建速度相较Neural Body、HumanNeRF和MonoHuman等人体重建方法提高17.7%、9.5%和37.5%,且重建精度更高,通过PP-Matting方法配合二值化操作将人体掩码提取精度提升至96%以上。

关键词: 三维人体重建, 神经辐射场, 体渲染加速, 人体掩码提取, 位置特征编码