Skeleton2D3D

Code for reproducing the results in the following paper:

This repo, together with image-play and pose-hg-train (branch image-play), hold the code for reproducing the results in the following paper:

Forecasting Human Dynamics from Static Images
Yu-Wei Chao, Jimei Yang, Brian Price, Scott Cohen, Jia Deng
IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2017

Check out the project site for more details.

Role

• The role of this repo is to implement training step 2 (Sec. 3.3), i.e. pre-training a 3D skeleton converter to recover 3D joint locations from 2D heatmaps.

• This is later used to initialize the 3D skeleton converter sub-network in training step 3 (Sec. 3.3), i.e. training the full system.

Citing Skeleton2D3D

Please cite Skeleton2D3D if it helps your research:

@INPROCEEDINGS{chao:cvpr2017,
  author = {Yu-Wei Chao and Jimei Yang and Brian Price and Scott Cohen and Jia Deng},
  booktitle = {Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition},
  title = {Forecasting Human Dynamics from Static Images},
  year = {2017},
}

Clone the Repository

This repo contains one submodules (pose-hg-train), so make sure you clone with --recursive:

git clone --recursive https://github.com/ywchao/skeleton2d3d.git

Contents

1. Download Pre-Computed Models and Prediction
2. Dependencies
3. Setting Up Human3.6M
4. Setting Up Penn Action
5. Training 3D Skeleton Converter on Ground-Truth Heatmaps
6. Fine-Tuning 3D Skeleton Converter on Predicted Heatmaps
7. Comparison with Zhou et al. [40]
8. Evaluation

Download Pre-Computed Models and Prediction

If you just want to run the training of the full system, i.e. image-play, you can simply download the pre-computed models and prediction (108M) and skip the remaining content.

./scripts/fetch_s2d3d_models_prediction.sh
./scripts/setup_symlinks_models.sh

This will populate the exp folder with precomputed_s2d3d_models_prediction and set up a set of symlinks.

You can also now set up Human3.6M and run the evaluation demo with the downloaded prediction. This will ensure exact reproduction of the paper's results.

Dependencies

To proceed to the remaining content, make sure the following are installed.

• Torch7
  • We used commit bd5e664 (2016-10-17) with CUDA 8.0.27 RC and cuDNN v5.1 (cudnn-8.0-linux-x64-v5.1).
  • All our models were trained on a GeForce GTX TITAN X GPU.
• matio-ffi
• torch-hdf5
• MATLAB

Setting Up Human3.6M

The Human3.6M dataset is used for training and evaluation.

1. Download the Human3.6M dataset. Only the Poses RawAngles and Videos files are required:

   Poses_RawAngles_S1.tgz
   Poses_RawAngles_S5.tgz
   Poses_RawAngles_S6.tgz
   Poses_RawAngles_S7.tgz
   Poses_RawAngles_S8.tgz
   Poses_RawAngles_S9.tgz
   Poses_RawAngles_S11.tgz
   Videos_S1.tgz
   Videos_S5.tgz
   Videos_S6.tgz
   Videos_S7.tgz
   Videos_S8.tgz
   Videos_S9.tgz
   Videos_S11.tgz

   Place these files under external/Human3.6M.

2. Extract the files:

   for i in external/Human3.6M/*.tgz; do tar zxvf $i -C external/Human3.6M; done

   This will populate the external/Human3.6M folder with S1, S5, S6, S7, S8, S9, and S11.

3. Download the Human3.6M dataset code:

   ./h36m_utils/fetch_h36m_code.sh

   This will populate the h36m_utils folder with Release-v1.1.

4. Generate meta files. Start MATLAB matlab under skeleton2d3d. You should see the message added paths for the experiment! followed by the MATLAB prompt >>. Run the following command:

   H36MDataBase.instance;

   Set the data path to external/Human3.6M and the config file directory to h36m_utils/Release-v1.1. This will create a new file H36M.conf under skeleton2d3d.

5. Preprocess data for training and evaluation:

   matlab -r "generate_data_h36m; quit"

   This will populate the data/h36m folder with frames, train.mat, and val.mat.

6. Optional: Visualize 3D pose sequences:

   matlab -r "vis_3d_pose; quit"

   The output will be saved in output/vis_3d_pose.

Setting Up Penn Action

The Penn Action dataset is used for running prediction.

1. Download the Penn Action dataset to external. external should contain Penn_Action.tar.gz. Extract the files:

   tar zxvf external/Penn_Action.tar.gz -C external

   This will populate the external folder with a folder Penn_Action with frames, labels, tools, and README.

2. Preprocess Penn Action by cropping the images:

   matlab -r "prepare_penn_crop; quit"

   This will populate the data/penn-crop folder with frames and labels.

3. Generate validation set and preprocess annotations:

   matlab -r "generate_valid_penn; quit"
   python tools/preprocess.py

   This will populate the data/penn-crop folder with valid_ind.txt, train.h5, val.h5, and test.h5.

Training 3D Skeleton Converter on Ground-Truth Heatmaps

We begin with training a 3D skeleton converter on Human3.6M. As the first step, we use ground-truth heatmaps as input to the network.

1. Before starting, make sure to remove the symlinks from the download section, if any:

   find exp -type l -delete

2. Optional: Visualize training examples. Each example consists of input ground-truth heamaps and ground-truth 3D pose. The heamaps are artificially generated by projecting 3D pose onto the image plane. This is done in Torch7 each time we load a training sample. We provide a way to visualize this process in MATLAB:

   matlab -r "vis_pose_proj; quit"

   The output will be saved in output/vis_pose_proj.

3. Start training:

   ./scripts/h36m/res-64.sh $GPU_ID

   The output will be saved in exp/h36m/res-64.

4. Optional: Visualize training loss and accuracy:

   matlab -r "plot_loss_err; quit"

   The output will be saved to output/plot_res-64.pdf.

5. Optional: Visualize prediction on a subset of the validation set:

   matlab -r "vis_preds_h36m; quit"

   The output will be saved in output/vis_res-64/h36m_val. The predicted pose is colored by blue, green, and red, and the ground-truth pose is colored by black, cyan, and magenta.

6. Optional: Run prediction on Penn Action. Given the Human3.6M trained model, we can run prediction on Penn Action. Again, we use ground-truth heatmaps as input to the network. Note that Penn Action contains unlabeled joints, which will introduce empty heatmaps that were not seen during training.

   ./scripts/penn-crop/res-64-pred.sh $GPU_ID

   The output will be saved in exp/penn-crop/res-64.

7. Optional: Visualize prediction on a subset of the validation set:

   matlab -r "vis_preds_penn; quit"

   The output will be saved in output/vis_res-64/penn_val.

Fine-Tuning 3D Skeleton Converter on Predicted Heatmaps

Rather than ground-trtuh heatmaps, often times the 3D skeleton converter is expected to take predicted heatmaps as input. We next fine-tune the pre-trained 3D skeleton converter on heatmaps produced by an hourglass network.

1. Obtain a trained hourglass model. This is done with the submodule pose-hg-train.

   Option 1: Download pre-computed hourglass models (50M): (recommended)

   cd pose-hg-train
   ./scripts/fetch_hg_models.sh
   ./scripts/setup_symlinks_models.sh
   cd ..

   This will populate the pose-hg-train/exp folder with precomputed_hg_models and set up a set of symlinks.

   Option 2: Train your own models.

2. Start training:

   ./scripts/h36m/hg-256-res-64-hg0-hgfix.sh $GPU_ID

   The output will be saved in exp/h36m/hg-256-res-64-hg0-hgfix.

3. Optional: Visualize training loss, error, and accuracy:

   matlab -r "plot_loss_err_acc; quit"

   The output will be saved to output/plot_hg-256-res-64-hg0-hgfix.pdf.

4. Optional: Visualize prediction on a subset of the validation set:

   matlab -r "vis_preds_h36m_hg; quit"

   The output will be saved in output/vis_hg-256-res-64-hg0-hgfix/h36m_val. The predicted pose is colored by blue, green, and red, and the ground-truth pose is colored by black, cyan, and magenta.

5. Optional: Run prediction on Penn Action. Again, rather than using ground-truth heatmaps as in the last section, we use predicted heatmaps as input here.

   ./scripts/penn-crop/hg-256-res-64-hg0-hgfix-pred.sh $GPU_ID

   The output will be saved in exp/penn-crop/hg-256-res-64-hg0-hgfix.

6. Optional: Visualize prediction on a subset of the validation set:

   matlab -r "vis_preds_penn_hg; quit"

   The output will be saved in output/vis_hg-256-res-64-hg0-hgfix/penn_val.

Comparison with Zhou et al. [40]

This demo shows how we compare 3D pose recovery with Zhou et al. [40] in the paper (Sec. 4.2).

1. Fine-tune the hourglass network on Human3.6M. We will use the hourglass output as input to Zhou et al.'s method. Our goal is to evaluate the 3D pose output on Human3.6M. Since the hourglass model from pose-hg-train is trained on MPII and Penn Action, we first fine-tune it on Human3.6M:

   ./scripts/h36m/hg-256.sh $GPU_ID

   The output will be saved in exp/h36m/hg-256.

2. Run prediction:

   ./scripts/h36m/hg-256-pred.sh $GPU_ID

   The output will be saved in exp/h36m/hg-256.

3. Download Zhou et al.'s MATLAB code:

   ./shapeconvex/fetch_shapeconvex.sh

   This will populate the shapeconvex folder with release.

4. Learn pose dictionary on Human3.6M:

   matlab -r "shapeconvex_dl; quit"

   The output will be saved to shapeconvex/shapeDict_h36m.mat.

5. Run 3D pose estimation:

   matlab -r "shapeconvex_run; quit"

   The output will be saved to shapeconvex/res_hg-256-pred/h36m_val.

6. Optional: Visualize prediction on a subset of the validation set:

   matlab -r "shapeconvex_vis; quit"

   The output will be saved to shapeconvex/vis_hg-256-pred/h36m_val.

7. Finally, for a fair comparison, we also need to fine-tune our 3D skeleton converter using the fine-tuned hourglass.

   ./scripts/h36m/hg-256-res-64-hg1-hgfix.sh $GPU_ID

   The output will be saved in exp/h36m/hg-256-res-64-hg1-hgfix.

Evaluation

This demo runs the MATLAB evaluation script and reproduces our results in the paper (Tab. 2). If you are using pre-computed prediction, and want to also output Zhou et al.'s results, make sure to first run step 3, 4, and 5 in the last section.

1. Compute mean per joint position errors (MPMJE):

   matlab -r "eval_run; quit"

   This will print out the MPMJE values.

2. Optional: Visualize Zhou et al.'s and our results.

   matlab -r "vis_run; quit"

   The output will be saved in evaluation/shapeconvex and evaluation/skeleton2d3d.