Diverse Point Cloud Completion with Geometry-Aware Transformers

PoinTr

PoinTr: Diverse Point Cloud Completion with Geometry-Aware Transformers

Created by Xumin Yu*, Yongming Rao*, Ziyi Wang, Zuyan Liu, Jiwen Lu, Jie Zhou

This repository contains PyTorch implementation for PoinTr: Diverse Point Cloud Completion with Geometry-Aware Transformers (ICCV 2021 Oral Presentation) [arXiv].

PoinTr is a transformer-based model for point cloud completion. By representing the point cloud as a set of unordered groups of points with position embeddings, we convert the point cloud to a sequence of point proxies and employ a transformer encoder-decoder architecture for generation. We also propose two more challenging benchmarks ShapeNet-55/34 with more diverse incomplete point clouds that can better reflect the real-world scenarios to promote future research.

Pretrained Models

We provide pretrained PoinTr models:

Usage

Requirements

• PyTorch >= 1.7.0
• python >= 3.7
• CUDA >= 9.0
• GCC >= 4.9
• torchvision
• timm
• open3d
• tensorboardX

pip install -r requirements.txt

Building Pytorch Extensions for Chamfer Distance, PointNet++ and kNN

NOTE: PyTorch >= 1.7 and GCC >= 4.9 are required.

# Chamfer Distance
bash install.sh
# PointNet++
pip install "git+git://github.com/erikwijmans/Pointnet2_PyTorch.git#egg=pointnet2_ops&subdirectory=pointnet2_ops_lib"
# GPU kNN
pip install --upgrade https://github.com/unlimblue/KNN_CUDA/releases/download/0.2/KNN_CUDA-0.2-py3-none-any.whl

Dataset

The details of our new ShapeNet-55/34 datasets and other existing datasets can be found in DATASET.md.

Evaluation

To evaluate a pre-trained PoinTr model on the Three Dataset with single GPU, run:

bash ./scripts/test.sh <GPU_IDS> --ckpts <path> --config <config> --exp_name <name> [--mode <easy/median/hard>]

Some examples:

Test the PoinTr pretrained model on the PCN benchmark:

bash ./scripts/test.sh 0 --ckpts ./pretrained/PoinTr_PCN.pth --config ./cfgs/PCN_models/PoinTr.yaml --exp_name example

Test the PoinTr pretrained model on ShapeNet55 benchmark (easy mode):

bash ./scripts/test.sh 0 --ckpts ./pretrained/PoinTr_ShapeNet55.pth --config ./cfgs/ShapeNet55_models/PoinTr.yaml --mode easy --exp_name example

Test the PoinTr pretrained model on the KITTI benchmark:

bash ./scripts/test.sh 0 --ckpts ./pretrained/PoinTr_KITTI.pth --config ./cfgs/KITTI_models/PoinTr.yaml --exp_name example

Training

To train a point cloud completion model from scratch, run:

# Use DistributedDataParallel (DDP)
bash ./scripts/dist_train.sh <NUM_GPU> <port> --config <config> --exp_name <name> [--resume] [--start_ckpts <path>] [--val_freq <int>]
# or just use DataParallel (DP)
bash ./scripts/train.sh <GPUIDS> --config <config> --exp_name <name> [--resume] [--start_ckpts <path>] [--val_freq <int>]

Some examples:

Train a PoinTr model on PCN benchmark with 2 gpus:

CUDA_VISIBLE_DEVICES=0,1 bash ./scripts/dist_train.sh 2 13232 --config ./cfgs/PCN_models/PoinTr.yaml --exp_name example

Resume a checkpoint:

CUDA_VISIBLE_DEVICES=0,1 bash ./scripts/dist_train.sh 2 13232 --config ./cfgs/PCN_models/PoinTr.yaml --exp_name example --resume

Finetune a PoinTr on PCNCars

CUDA_VISIBLE_DEVICES=0,1 bash ./scripts/dist_train.sh 2 13232 --config ./cfgs/KITTI_models/PoinTr.yaml --exp_name example --start_ckpts ./weight.pth

Train a PoinTr model with a single GPU:

bash ./scripts/train.sh 0 --config ./cfgs/KITTI_models/PoinTr.yaml --exp_name example

We also provide the Pytorch implementation of several baseline models including GRNet, PCN, TopNet and FoldingNet. For example, to train a GRNet model on ShapeNet-55, run:

CUDA_VISIBLE_DEVICES=0,1 bash ./scripts/dist_train.sh 2 13232 --config ./cfgs/ShapeNet55_models/GRNet.yaml --exp_name example

Completion Results on ShapeNet55 and KITTI-Cars

License

MIT License

Acknowledgements

Our code is inspired by GRNet and mmdetection3d.

Citation

If you find our work useful in your research, please consider citing:

@inproceedings{yu2021pointr,
  title={PoinTr: Diverse Point Cloud Completion with Geometry-Aware Transformers},
  author={Yu, Xumin, Rao, Yongming and Wang, Ziyi and Liu, Zuyan, and Lu, Jiwen and Zhou, Jie},
  booktitle={ICCV},
  year={2021}
}

GitHub

https://github.com/yuxumin/PoinTr