# Waymo Dataset¶

## Prepare dataset¶

Before preparing Waymo dataset, if you only installed requirements in requirements/build.txt and requirements/runtime.txt before, please install the official package for this dataset at first by running

# tf 2.1.0.
pip install waymo-open-dataset-tf-2-1-0==1.2.0
# tf 2.0.0
# pip install waymo-open-dataset-tf-2-0-0==1.2.0
# tf 1.15.0
# pip install waymo-open-dataset-tf-1-15-0==1.2.0

or

pip install -r requirements/optional.txt

Like the general way to prepare dataset, it is recommended to symlink the dataset root to $MMDETECTION3D/data. Due to the original Waymo data format is based on tfrecord, we need to preprocess the raw data for convenient usage in the training and evaluation procedure. Our approach is to convert them into KITTI format. The folder structure should be organized as follows before our processing. mmdetection3d ├── mmdet3d ├── tools ├── configs ├── data │ ├── waymo │ │ ├── waymo_format │ │ │ ├── training │ │ │ ├── validation │ │ │ ├── testing │ │ │ ├── gt.bin │ │ ├── kitti_format │ │ │ ├── ImageSets You can download Waymo open dataset V1.2 HERE and its data split HERE. Then put tfrecord files into corresponding folders in data/waymo/waymo_format/ and put the data split txt files into data/waymo/kitti_format/ImageSets. Download ground truth bin files for validation set HERE and put it into data/waymo/waymo_format/. A tip is that you can use gsutil to download the large-scale dataset with commands. You can take this tool as an example for more details. Subsequently, prepare Waymo data by running python tools/create_data.py waymo --root-path ./data/waymo/ --out-dir ./data/waymo/ --workers 128 --extra-tag waymo Note that if your local disk does not have enough space for saving converted data, you can change the --out-dir to anywhere else. Just remember to create folders and prepare data there in advance and link them back to data/waymo/kitti_format after the data conversion. After the data conversion, the folder structure and info files should be organized as below. mmdetection3d ├── mmdet3d ├── tools ├── configs ├── data │ ├── waymo │ │ ├── waymo_format │ │ │ ├── training │ │ │ ├── validation │ │ │ ├── testing │ │ │ ├── gt.bin │ │ ├── kitti_format │ │ │ ├── ImageSets │ │ │ ├── training │ │ │ │ ├── calib │ │ │ │ ├── image_0 │ │ │ │ ├── image_1 │ │ │ │ ├── image_2 │ │ │ │ ├── image_3 │ │ │ │ ├── image_4 │ │ │ │ ├── label_0 │ │ │ │ ├── label_1 │ │ │ │ ├── label_2 │ │ │ │ ├── label_3 │ │ │ │ ├── label_4 │ │ │ │ ├── label_all │ │ │ │ ├── pose │ │ │ │ ├── velodyne │ │ │ ├── testing │ │ │ │ ├── (the same as training) │ │ │ ├── waymo_gt_database │ │ │ ├── waymo_infos_trainval.pkl │ │ │ ├── waymo_infos_train.pkl │ │ │ ├── waymo_infos_val.pkl │ │ │ ├── waymo_infos_test.pkl │ │ │ ├── waymo_dbinfos_train.pkl Here because there are several cameras, we store the corresponding image and labels that can be projected to that camera respectively and save pose for further usage of consecutive frames point clouds. We use a coding way {a}{bbb}{ccc} to name the data for each frame, where a is the prefix for different split (0 for training, 1 for validation and 2 for testing), bbb for segment index and ccc for frame index. You can easily locate the required frame according to this naming rule. We gather the data for training and validation together as KITTI and store the indices for different set in the ImageSet files. ## Training¶ Considering there are many similar frames in the original dataset, we can basically use a subset to train our model primarily. In our preliminary baselines, we load one frame every five frames, and thanks to our hyper parameters settings and data augmentation, we obtain a better result compared with the performance given in the original dataset paper. For more details about the configuration and performance, please refer to README.md in the configs/pointpillars/. A more complete benchmark based on other settings and methods is coming soon. ## Evaluation¶ For evaluation on Waymo, please follow the instruction to build the binary file compute_detection_metrics_main for metrics computation and put it into mmdet3d/core/evaluation/waymo_utils/. Basically, you can follow the commands below to install bazel and build the file. # download the code and enter the base directory git clone https://github.com/waymo-research/waymo-open-dataset.git waymo-od cd waymo-od git checkout remotes/origin/master # use the Bazel build system sudo apt-get install --assume-yes pkg-config zip g++ zlib1g-dev unzip python3 python3-pip BAZEL_VERSION=3.1.0 wget https://github.com/bazelbuild/bazel/releases/download/${BAZEL_VERSION}/bazel-${BAZEL_VERSION}-installer-linux-x86_64.sh sudo bash bazel-${BAZEL_VERSION}-installer-linux-x86_64.sh
sudo apt install build-essential

# configure .bazelrc
./configure.sh
# delete previous bazel outputs and reset internal caches
bazel clean

bazel build waymo_open_dataset/metrics/tools/compute_detection_metrics_main
cp bazel-bin/waymo_open_dataset/metrics/tools/compute_detection_metrics_main ../mmdetection3d/mmdet3d/core/evaluation/waymo_utils/

Then you can evaluate your models on Waymo. An example to evaluate PointPillars on Waymo with 8 GPUs with Waymo metrics is as follows.

./tools/slurm_test.sh ${PARTITION}${JOB_NAME} configs/pointpillars/hv_pointpillars_secfpn_sbn-2x16_2x_waymo-3d-car.py \
checkpoints/hv_pointpillars_secfpn_sbn-2x16_2x_waymo-3d-car_latest.pth --out results/waymo-car/results_eval.pkl \
--eval waymo --eval-options 'pklfile_prefix=results/waymo-car/kitti_results' \
'submission_prefix=results/waymo-car/kitti_results'

pklfile_prefix should be given in the --eval-options if the bin file is needed to be generated. For metrics, waymo is the recommended official evaluation prototype. Currently, evaluating with choice kitti is adapted from KITTI and the results for each difficulty are not exactly the same as the definition of KITTI. Instead, most of objects are marked with difficulty 0 currently, which will be fixed in the future. The reasons of its instability include the large computation for evaluation, the lack of occlusion and truncation in the converted data, different definitions of difficulty and different methods of computing Average Precision.

Notice:

1. Sometimes when using bazel to build compute_detection_metrics_main, an error 'round' is not a member of 'std' may appear. We just need to remove the std:: before round in that file.

2. Considering it takes a little long time to evaluate once, we recommend to evaluate only once at the end of model training.

3. To use TensorFlow with CUDA 9, it is recommended to compile it from source. Apart from official tutorials, you can refer to this link for possibly suitable precompiled packages and useful information for compiling it from source.

## Testing and make a submission¶

An example to test PointPillars on Waymo with 8 GPUs, generate the bin files and make a submission to the leaderboard.

./tools/slurm_test.sh ${PARTITION}${JOB_NAME} configs/pointpillars/hv_pointpillars_secfpn_sbn-2x16_2x_waymo-3d-car.py \
checkpoints/hv_pointpillars_secfpn_sbn-2x16_2x_waymo-3d-car_latest.pth --out results/waymo-car/results_eval.pkl \
--format-only --eval-options 'pklfile_prefix=results/waymo-car/kitti_results' \
'submission_prefix=results/waymo-car/kitti_results'

After generating the bin file, you can simply build the binary file create_submission and use them to create a submission file by following the instruction. Basically, here are some example commands.

cd ../waymo-od/
bazel build waymo_open_dataset/metrics/tools/create_submission
cp bazel-bin/waymo_open_dataset/metrics/tools/create_submission ../mmdetection3d/mmdet3d/core/evaluation/waymo_utils/
vim waymo_open_dataset/metrics/tools/submission.txtpb  # set the metadata information
cp waymo_open_dataset/metrics/tools/submission.txtpb ../mmdetection3d/mmdet3d/core/evaluation/waymo_utils/

cd ../mmdetection3d
# suppose the result bin is in results/waymo-car/submission
mmdet3d/core/evaluation/waymo_utils/create_submission  --input_filenames='results/waymo-car/kitti_results_test.bin' --output_filename='results/waymo-car/submission/model' --submission_filename='mmdet3d/core/evaluation/waymo_utils/submission.txtpb'

tar cvf results/waymo-car/submission/my_model.tar results/waymo-car/submission/my_model/
gzip results/waymo-car/submission/my_model.tar

For evaluation on the validation set with the eval server, you can also use the same way to generate a submission. Make sure you change the fields in submission.txtpb before running the command above.