Direct-PoseNet: Absolute Pose Regression with Photometric Consistency

Shuai Chen, Zirui Wang, and Victor Prisacariu (3DV 2021)

Project Page | Paper

Setup

Installing Requirements

We tested our code based on CUDA10.1+, PyTorch 1.7.1+, and Python 3.6.9+ using docker.

We also used tensorflow-graphics library in our evaluation code for get_error_in_q(). Update: The dependencies of this package could be easily replaced by the latest pytorch3d library if you wish to run the code without any tensorflow packages.

Rest of dependencies are in requirement.txt

Data Preparation

• 7Scenes

We use similar data preparation as in MapNet. You can download the 7-Scenes datasets to the data/deepslam_data directory.

Or you can use simlink

cd data/deepslam_data && ln -s 7SCENES_DIR 7Scenes

Notice that we additionally computed a pose averaging stats (pose_avg_stats.txt) in data/7Scenes to align the 7Scenes' coordinate system with NeRF's coordinate system. You could re-align

• LLFF

You can download the LLFF dataset via google drive.

cd data
(DOWNLOAD nerf_llff_data.zip into data/)
unzip nerf_llff_data.zip
cd ..

Training

Our method relies on a pretrained NeRF model and a pretrained pose regression model as we stated in the paper. The followings are examples to train the models.

• NeRF model (7-Scenes)

python run_nerf.py --config config_nerf.txt

• NeRF model (LLFF)

python run_nerf.py --config configs/fern.txt

• Pose regression baseline model

python train.py --config config_pn.txt

• Direct-PoseNet model

python train.py --config config_direct_pn.txt

• Direct-PoseNet + Unlabeled model

python train.py --config config_direct_pn_unlabel.txt

Evaluation

We provide methods to evaluate our direct-pn and direct-pn+U models.

• To evaluate the NeRF model in PSNR, simply add --render_test argument. To save rendered images as videos, add --render_video_train or --render_video_test

python run_nerf.py --config config_nerf.txt --render_test

• To evaluate APR performance of the pose regression baseline model, Direct-pn, or Direct-pn+U model, you can just add --eval --testskip=1 --pretrain_model_path=../logs/PATH_TO_CHECKPOINT. For example:

python train.py --config config_direct_pn.txt --eval --testskip=1 --pretrain_model_path=../logs/direct_pn_heads/checkpoint.pt

Pre-trained model

We currently provide the 7-Scenes models in our paper. You can download our paper models using this link. We suggest the models to be put in a new directory (./logs/) of the project

Acknowledgement

We thank Kejie Li for his advice on experimental design and generous help to polish our paper. We also appreciate Henry Howard-Jenkins and Theo W. Costain for some great comments and discussions.

Our NeRF code is modified based on nerf-pytorch. Thanks for their excellent work!

Citation

@inproceedings{chen2021direct,
  title={Direct-PoseNet: Absolute pose regression with photometric consistency},
  author={Chen, Shuai and Wang, Zirui and Prisacariu, Victor},
  booktitle={2021 International Conference on 3D Vision (3DV)},
  pages={1175--1185},
  year={2021},
  organization={IEEE}
}