LION: Latent Point Diffusion Models for 3D Shape Generation

NeurIPS 2022

Xiaohui Zeng   Arash Vahdat   Francis Williams   Zan Gojcic   Or Litany   Sanja Fidler   Karsten Kreis

Paper   Project Page

Update

• add pointclouds rendering code used for paper figure, see utils/render_mitsuba_pc.py
• When opening an issue, please add @ZENGXH so that I can reponse faster!

Install

• Dependencies:

  • CUDA 11.6

• Setup the environment Install from conda file

      conda env create --name lion_env --file=env.yaml 
      conda activate lion_env 
  
      # Install some other packages 
      pip install git+https://github.com/openai/CLIP.git 
  
      # build some packages first (optional)
      python build_pkg.py
  

  Tested with conda version 22.9.0

• Using Docker

  • build the docker with bash ./docker/build_docker.sh
  • launch the docker with bash ./docker/run.sh

Demo

run python demo.py, will load the released text2shape model on hugging face and generate a chair point cloud. (Note: the checkpoint is not released yet, the files loaded in the demo.py file is not available at this point)

Released checkpoint and samples

• will be release soon
• after download, run the checksum with python ./script/check_sum.py ./lion_ckpt.zip
• put the downloaded file under ./lion_ckpt/

Training

data

• ShapeNet can be downloaded here.
• Put the downloaded data as ./data/ShapeNetCore.v2.PC15k or edit the pointflow entry in ./datasets/data_path.py for the ShapeNet dataset path.

train VAE

• run bash ./script/train_vae.sh $NGPU (the released checkpoint is trained with NGPU=4 on A100)
• if want to use comet to log the experiment, add .comet_api file under the current folder, write the api key as {"api_key": "${COMET_API_KEY}"} in the .comet_api file

train diffusion prior

• require the vae checkpoint
• run bash ./script/train_prior.sh $NGPU (the released checkpoint is trained with NGPU=8 with 2 node on V100)

(Optional) monitor exp

• (tested) use comet-ml: need to add a file .comet_api under this LION folder, example of the .comet_api file:

{"api_key": "...", "project_name": "lion", "workspace": "..."}

• (not tested) use wandb: need to add a .wandb_api file, and set the env variable export USE_WB=1 before training

{"project": "...", "entity": "..."}

• (not tested) use tensorboard, set the env variable export USE_TFB=1 before training
• see the utils/utils.py files for the details of the experiment logger; I usually use comet-ml for my experiments

evaluate a trained prior

• download the test data (Table 1) from here, unzip and put it as ./datasets/test_data/
• download the released checkpoint from above

checkpoint="./lion_ckpt/unconditional/airplane/checkpoints/model.pt" 
bash ./script/eval.sh $checkpoint  # will take 1-2 hour 

other test data

• ShapeNet-Vol test data:
  • please check here before using this data
  • all category: 1000 shapes are sampled from the full validation set
  • chair, airplane, car
• table 21 and table 20, point-flow test data
  • check here before using this data
  • mug and bottle
  • 55 catergory data

Evaluate the samples with the 1-NNA metrics

• download the test data from here, unzip and put it as ./datasets/test_data/
• run python ./script/compute_score.py (Note: for ShapeNet-Vol data and table 21, 20, need to set norm_box=True)

Citation

@inproceedings{zeng2022lion,
    title={LION: Latent Point Diffusion Models for 3D Shape Generation},
        author={Xiaohui Zeng and Arash Vahdat and Francis Williams and Zan Gojcic and Or Litany and Sanja Fidler and Karsten Kreis},
        booktitle={Advances in Neural Information Processing Systems (NeurIPS)},
        year={2022}
}