Before mmdet3d version 1.0.0rc4 we sampled 50000 points following VoteNet preprocessing. Since 1.0.0v4 version we do not limit the maximum number of points during preprocessing, giving the users more flexibility with PointSample
. The SUN RGB-D annotations should be updated in case the user wants to achieve best metrics for models supporting more than 50000 input points.
Please refer to the SUN RGB-D README.md for more details.
We fixed a bug in tools/data_converter/s3dis_data_utils.py
leading to miss not more than one object per scene. Users need to regenerate the annotations with tools/create_data.py
.
We have adopted CUDA operators compiled from mmcv and removed all the CUDA operators in mmdet3d. We now do not need to compile the CUDA operators in mmdet3d anymore.
In this version we did a major code refactoring that boosted the performance of waymo dataset conversion by multiprocessing. Meanwhile, we also fixed the imprecise timestamps saving issue in waymo dataset conversion. This change introduces following backward compatibility breaks:
- The point cloud .bin files of waymo dataset need to be regenerated.
In the .bin files each point occupies 6
float32
and the meaning of the lastfloat32
now changed from imprecise timestamps to range frame offset. The range frame offset for each point is calculated asri * h * w + row * w + col
if the point is from the TOP lidar or-1
otherwise. Theh
,w
denote the height and width of the TOP lidar's range frame. Theri
,row
,col
denote the return index, the row and the column of the range frame where each point locates. Following tables show the difference across the change:
Before
Element offset (float32) | 0 | 1 | 2 | 3 | 4 | 5 |
---|---|---|---|---|---|---|
Bytes offset | 0 | 4 | 8 | 12 | 16 | 20 |
Meaning | x | y | z | intensity | elongation | imprecise timestamp |
After
Element offset (float32) | 0 | 1 | 2 | 3 | 4 | 5 |
---|---|---|---|---|---|---|
Bytes offset | 0 | 4 | 8 | 12 | 16 | 20 |
Meaning | x | y | z | intensity | elongation | range frame offset |
- The objects' point cloud .bin files in the GT-database of waymo dataset need to be regenerated because we also dumped the range frame offset for each point into it. Following tables show the difference across the change:
Before
Element offset (float32) | 0 | 1 | 2 | 3 | 4 |
---|---|---|---|---|---|
Bytes offset | 0 | 4 | 8 | 12 | 16 |
Meaning | x | y | z | intensity | elongation |
After
Element offset (float32) | 0 | 1 | 2 | 3 | 4 | 5 |
---|---|---|---|---|---|---|
Bytes offset | 0 | 4 | 8 | 12 | 16 | 20 |
Meaning | x | y | z | intensity | elongation | range frame offset |
- Any configuration that uses waymo dataset with GT Augmentation should change the
db_sampler.points_loader.load_dim
from5
to6
.
In this version, we did a major code refactoring which improved the consistency among the three coordinate systems (and corresponding box representation), LiDAR, Camera, and Depth. A brief summary for this refactoring is as follows:
- The three coordinate systems are all right-handed now (which means the yaw angle increases in the counterclockwise direction).
- The LiDAR system
(x_size, y_size, z_size)
corresponds to(l, w, h)
instead of(w, l, h)
. This is more natural sincel
is parallel with the direction where the yaw angle is zero, and we prefer using the positive direction of thex
axis as that direction, which is exactly how we define yaw angle in Depth and Camera coordinate systems. - The APIs for box-related operations are improved and now are more user-friendly.
Since definitions of box representation have changed, the annotation data of most datasets require updating:
- SUN RGB-D: Yaw angles in the annotation should be reversed.
- KITTI: For LiDAR boxes in GT databases, (x_size, y_size, z_size, yaw) out of (x, y, z, x_size, y_size, z_size) should be converted from the old LiDAR coordinate system to the new one. The training/validation data annotations should be left unchanged since they are under the Camera coordinate system, which is unmodified after the refactoring.
- Waymo: Same as KITTI.
- nuScenes: For LiDAR boxes in training/validation data and GT databases, (x_size, y_size, z_size, yaw) out of (x, y, z, x_size, y_size, z_size) should be converted.
- Lyft: Same as nuScenes.
Please regenerate the data annotation/GT database files or use update_data_coords.py
to update the data.
To use boxes under Depth and LiDAR coordinate systems, or to convert boxes between different coordinate systems, users should be aware of the difference between the old and new definitions. For example, the rotation, flipping, and bev functions of DepthInstance3DBoxes
and LiDARInstance3DBoxes
and box conversion functions have all been reimplemented in the refactoring.
Consequently, functions like output_to_lyft_box
undergo small modification to adapt to the new LiDAR/Depth box.
Since the LiDAR system (x_size, y_size, z_size)
now corresponds to (l, w, h)
instead of (w, l, h)
, the anchor sizes for LiDAR boxes are also changed, e.g., from [1.6, 3.9, 1.56]
to [3.9, 1.6, 1.56]
.
Functions only involving points are generally unaffected except if they rely on some refactored utility functions such as rotation_3d_in_axis
.
array_converter
: Please refer to array_converter.py. Functions wrapped witharray_converter
can convert array-like input types oftorch.Tensor
,np.ndarray
, andlist/tuple/float
totorch.Tensor
to process in an unified PyTorch pipeline. The result may finally be converted back to the input type. Most functions in utils.py are wrapped witharray_converter
.points_in_boxes
andpoints_in_boxes_batch
will be deprecated soon. They are renamed topoints_in_boxes_part
andpoints_in_boxes_all
respectively, with more detailed docstrings. The major difference of the two functions is that if a point is enclosed by multiple boxes,points_in_boxes_part
will only return the index of the first enclosing box whilepoints_in_boxes_all
will return all the indices of enclosing boxes.rotation_3d_in_axis
: Please refer to utils.py. Now this function supports multiple input types and more options. The function with the same name in box_np_ops.py is deleted since we do not need another function to tackle with NumPy data.rotation_2d
,points_cam2img
, andlimit_period
in box_np_ops.py are also deleted for the same reason.bev
method ofCameraInstance3DBoxes
: Changed it to be consistent with the definition of bev in Depth and LiDAR coordinate systems.- Data augmentation utils in data_augment_utils.py now follow the rules of a right-handed system.
- We do not need the yaw hacking in KITTI anymore after refining
get_direction_target
. Interested users may refer to PR #677 .
We modified the returned grouped_xyz
value of operation QueryAndGroup
to support PAConv segmentor. Originally, the grouped_xyz
is centered by subtracting the grouping centers, which represents the relative positions of grouped points. Now, we didn't perform such subtraction and the returned grouped_xyz
stands for the absolute coordinates of these points.
Note that, the other returned variables of QueryAndGroup
such as new_features
, unique_cnt
and grouped_idx
are not affected.
We remove the rotation and dimension hack in the monocular 3D detection on nuScenes. Specifically, we transform the rotation and dimension of boxes defined by nuScenes devkit to the coordinate system of our CameraInstance3DBoxes
in the pre-processing and transform them back in the post-processing. In this way, we can remove the corresponding hack used in the visualization tools. The modification also guarantees the correctness of all the operations based on our CameraInstance3DBoxes
(such as NMS and flip augmentation) when training monocular 3D detectors.
The modification only influences nuScenes coco-style json files. Please re-run the nuScenes data preparation script if necessary. See more details in the PR #744.
We adopt a new pre-processing procedure for the ScanNet dataset in order to support ImVoxelNet, which is a multi-view method requiring image data. In previous versions of MMDetection3D, ScanNet dataset was only used for point cloud based 3D detection and segmentation methods. We plan adding ImVoxelNet to our model zoo, thus updating ScanNet correspondingly by adding image-related pre-processing steps. Specifically, we made these changes:
- Add script for extracting RGB data.
- Update script for annotation creating.
- Add instructions in the documents on preparing image data.
Please refer to the ScanNet README.md for more details.
In order to fix the problem that the priority of EvalHook is too low, all hook priorities have been re-adjusted in 1.3.8, so MMDetection 2.14.0 needs to rely on the latest MMCV 1.3.8 version. For related information, please refer to #1120, for related issues, please refer to #5343.
To unify the parameter initialization in OpenMMLab projects, MMCV supports BaseModule
that accepts init_cfg
to allow the modules' parameters initialized in a flexible and unified manner. Now the users need to explicitly call model.init_weights()
in the training script to initialize the model (as in here, previously this was handled by the detector. Please refer to PR #622 for details.
We modified the dataset augmentation function BackgroundPointsFilter
(here). In previous version of MMdetection3D, BackgroundPointsFilter
changes the gt_bboxes_3d's bottom center to the gravity center. In MMDetection3D 0.15.0,
BackgroundPointsFilter
will not change it. Please refer to PR #609 for details.
We enhance the pipeline function IndoorPatchPointSample
used in point cloud segmentation task by adding more choices for patch selection. Also, we plan to remove the unused parameter sample_rate
in the future. Please modify the code as well as the config files accordingly if you use this transform.
We remove a useless parameter label_weight
from segmentation datasets including Custom3DSegDataset
, ScanNetSegDataset
and S3DISSegDataset
since this weight is utilized in the loss function of model class. Please modify the code as well as the config files accordingly if you use or inherit from these codes.
We adopt new pre-processing and conversion steps of ScanNet dataset. In previous versions of MMDetection3D, ScanNet dataset was only used for 3D detection task, where we trained on the training set and tested on the validation set. In MMDetection3D 0.14.0, we further support 3D segmentation task on ScanNet, which includes online benchmarking on test set. Since the alignment matrix is not provided for test set data, we abandon the alignment of points in data generation steps to support both tasks. Besides, as 3D segmentation requires per-point prediction, we also remove the down-sampling step in data generation.
-
In the new ScanNet processing scripts, we save the unaligned points for all the training, validation and test set. For train and val set with annotations, we also store the
axis_align_matrix
in data infos. For ground-truth bounding boxes, we store boxes in both aligned and unaligned coordinates with keygt_boxes_upright_depth
and keyunaligned_gt_boxes_upright_depth
respectively in data infos. -
In
ScanNetDataset
, we now load theaxis_align_matrix
as a part of data annotations. If it is not contained in old data infos, we will use identity matrix for compatibility. We also add a transform functionGlobalAlignment
in ScanNet detection data pipeline to align the points. -
Since the aligned boxes share the same key as in old data infos, we do not need to modify the code related to it. But do remember that they are not in the same coordinate system as the saved points.
-
There is an
PointSample
pipeline in the data pipelines for ScanNet detection task which down-samples points. So removing down-sampling in data generation will not affect the code.
We have trained a VoteNet model on the newly processed ScanNet dataset and get similar benchmark results. In order to prepare ScanNet data for both detection and segmentation tasks, please re-run the new pre-processing scripts following the ScanNet README.md.
We adopt a new pre-processing procedure for the SUNRGBD dataset in order to support ImVoteNet, which is a multi-modality method requiring both image and point cloud data. In previous versions of MMDetection3D, SUNRGBD dataset was only used for point cloud based 3D detection methods. In MMDetection3D 0.12.0, we add ImVoteNet to our model zoo, thus updating SUNRGBD correspondingly by adding image-related pre-processing steps. Specifically, we made these changes:
- Fix a bug in the image file path in meta data.
- Convert calibration matrices from double to float to avoid type mismatch in further operations.
- Add instructions in the documents on preparing image data.
Please refer to the SUNRGBD README.md for more details.
In MMDetection 0.6.0, we updated the model structures of VoteNet and H3DNet, therefore model checkpoints generated by MMDetection < 0.6.0 should be first converted to a format compatible with the latest structures via convert_votenet_checkpoints.py and convert_h3dnet_checkpoints.py . For more details, please refer to the VoteNet README.md and H3DNet README.md.