SeSDF: Self-evolved Signed Distance Field for Implicit 3D Clothed Human Reconstruction

Yukang Cao, Kai Han, Kwan-Yee K. Wong

Please refer to our webpage for more visualizations.

We address the problem of clothed human reconstruction from a single image or uncalibrated multi-view images. Existing methods struggle with reconstructing detailed geometry of a clothed human and often require a calibrated setting for multi-view reconstruction. We propose a flexible framework which, by leveraging the parametric SMPL-X model, can take an arbitrary number of input images to reconstruct a clothed human model under an uncalibrated setting. At the core of our framework is our novel self-evolved signed distance field (SeSDF) module which allows the framework to learn to deform the signed distance field (SDF) derived from the fitted SMPL-X model, such that detailed geometry reflecting the actual clothed human can be encoded for better reconstruction. Besides, we propose a simple method for self-calibration of multi-view images via the fitted SMPL-X parameters. This lifts the requirement of tedious manual calibration and largely increases the flexibility of our method. Further, we introduce an effective occlusion-aware feature fusion strategy to account for the most useful features to reconstruct the human model. We thoroughly evaluate our framework on public benchmarks, and our framework establishes a new state-of-the-art.

The environment (in conda yaml) for SeSDF training and testing.

conda env create -f environment_sesdf.yaml
conda activate sesdf

You may also need to install torch_scatter manually for the 3D encoder

pip install torch==1.10.0+cu102 torchvision==0.11.0+cu102 torchaudio==0.10.0 -f https://download.pytorch.org/whl/torch_stable.html
pip install torch-scatter==2.0.9 -f https://pytorch-geometric.com/whl/torch-1.10.0+cu102.html

If you are using RTX 3090 or higher, please install torch, torchvision, and torch-scatter correspondingly, i.e.,

pip install torch==1.10.0+cu111 torchvision==0.11.1+cu111 torchaudio==0.10.0 -f https://download.pytorch.org/whl/torch_stable.html
pip install torch-scatter==2.0.9 -f https://pytorch-geometric.com/whl/torch-1.10.0+cu111.html

Follow pytorch3d and kaolin to install the required package.

We use THUman2.0 dataset for training and testing. You can download it and corresponding SMPL-X parameters and meshes from this link after following the instruction and sending the request form.

1. Generating the precomputed radiance transfer (PRT) for each obj mesh as in instructed in PIFu:

cd process_data
python -m prt_util -i {path_to_THUman2.0_dataset}

2. Rendering the meshes into 360-degree images. Together with RENDER folder for images, it will generate the MASK, PARAM, UV_RENDER, UV_MASK, UV_NORMAL, UV_POS, and copy the meshes to GEO/OBJ. Remember to add -e to enable EGL rendering.

python -m render_data -i {path_to_THUman2.0_dataset} -o {path_to_THUman2.0_processed_for_training} -e
cd ..

After data preprocessing, the dataset directory would be like:

THU2_processed/
├── UV_RENDER
├── UV_POS
├── UV_NORMAL
├── UV_MASK
├── PARAM
├── MASK
├── GEO/OBJ
├── SMPLX
├── val.txt

Training the single-view pipeline (The intermediate results and checkpoints are saved under ./results and ./checkpoints respectively.)

cd ./single-view
python -m apps.train_shape --dataroot {path_to_processed_THUman2.0_processed} --random_flip --random_scale --num_stack 4 --num_hourglass 2 --resolution 512 --hg_down 'ave_pool' --norm 'group' --val_train_error --val_test_error --gpu_ids=0,1,2 --batch_size 3 --learning_rate 0.0001 --sigma 0.02 --checkpoints_path {your_checkpoints_folder} --results_path {your_results_folder} --schedule 4 --num_threads 10

Training the multi-view pipeline

cd ../multi-view
python -m apps.train_shape --dataroot {path_to_processed_THUman2.0_processed} --random_flip --random_scale --num_stack 4 --num_hourglass 2 --resolution 512 --hg_down 'ave_pool' --norm 'group' --val_train_error --val_test_error --gpu_id=0 --batch_size 1 --learning_rate 0.0001 --sigma 0.02 --checkpoints_path {your_checkpoints_folder} --results_path {your_results_folder} --schedule 4 --num_threads 10 --num_views 3

See {your_results_folder}/pred.ply for intermediate visualizations during training.

Testing with the single-view pipeline (we follow a similar approach in ICON to obtain the estimated SMPL-X model.)

python ./apps/eval.py --batch_size 1 --num_stack 4 --num_hourglass 2 --resolution 512 --hg_down 'ave_pool' --norm 'group' --norm_color 'group' --test_folder_path {path_to_your_testdata} --load_netG_checkpoint_path {path_to_your_netG_checkpoint}

If you want to cite our work, please use the following bib entry:

@inproceedings{cao2023sesdf,
author    = {Yukang Cao and Kai Han and Kwan-Yee K. Wong},
title     = {SeSDF: Self-evolved Signed Distance Field for Implicit 3D Clothed Human Reconstruction},
booktitle = {IEEE Conference on Computer Vision and Pattern Recognition (CVPR)},
year      = {2023},
}