bev-project/mmdet3d/ops/pointnet_modules/point_sa_module.py

355 lines
13 KiB
Python
Raw Normal View History

2022-06-03 12:21:18 +08:00
import torch
from mmcv.cnn import ConvModule
from torch import nn as nn
from torch.nn import functional as F
from mmdet3d.ops import GroupAll, PAConv, Points_Sampler, QueryAndGroup, gather_points
from .builder import SA_MODULES
class BasePointSAModule(nn.Module):
"""Base module for point set abstraction module used in PointNets.
Args:
num_point (int): Number of points.
radii (list[float]): List of radius in each ball query.
sample_nums (list[int]): Number of samples in each ball query.
mlp_channels (list[list[int]]): Specify of the pointnet before
the global pooling for each scale.
fps_mod (list[str]: Type of FPS method, valid mod
['F-FPS', 'D-FPS', 'FS'], Default: ['D-FPS'].
F-FPS: using feature distances for FPS.
D-FPS: using Euclidean distances of points for FPS.
FS: using F-FPS and D-FPS simultaneously.
fps_sample_range_list (list[int]): Range of points to apply FPS.
Default: [-1].
dilated_group (bool): Whether to use dilated ball query.
Default: False.
use_xyz (bool): Whether to use xyz.
Default: True.
pool_mod (str): Type of pooling method.
Default: 'max_pool'.
normalize_xyz (bool): Whether to normalize local XYZ with radius.
Default: False.
grouper_return_grouped_xyz (bool): Whether to return grouped xyz in
`QueryAndGroup`. Defaults to False.
grouper_return_grouped_idx (bool): Whether to return grouped idx in
`QueryAndGroup`. Defaults to False.
"""
def __init__(
self,
num_point,
radii,
sample_nums,
mlp_channels,
fps_mod=["D-FPS"],
fps_sample_range_list=[-1],
dilated_group=False,
use_xyz=True,
pool_mod="max",
normalize_xyz=False,
grouper_return_grouped_xyz=False,
grouper_return_grouped_idx=False,
):
super(BasePointSAModule, self).__init__()
assert len(radii) == len(sample_nums) == len(mlp_channels)
assert pool_mod in ["max", "avg"]
assert isinstance(fps_mod, list) or isinstance(fps_mod, tuple)
assert isinstance(fps_sample_range_list, list) or isinstance(fps_sample_range_list, tuple)
assert len(fps_mod) == len(fps_sample_range_list)
if isinstance(mlp_channels, tuple):
mlp_channels = list(map(list, mlp_channels))
self.mlp_channels = mlp_channels
if isinstance(num_point, int):
self.num_point = [num_point]
elif isinstance(num_point, list) or isinstance(num_point, tuple):
self.num_point = num_point
else:
raise NotImplementedError("Error type of num_point!")
self.pool_mod = pool_mod
self.groupers = nn.ModuleList()
self.mlps = nn.ModuleList()
self.fps_mod_list = fps_mod
self.fps_sample_range_list = fps_sample_range_list
self.points_sampler = Points_Sampler(
self.num_point, self.fps_mod_list, self.fps_sample_range_list
)
for i in range(len(radii)):
radius = radii[i]
sample_num = sample_nums[i]
if num_point is not None:
if dilated_group and i != 0:
min_radius = radii[i - 1]
else:
min_radius = 0
grouper = QueryAndGroup(
radius,
sample_num,
min_radius=min_radius,
use_xyz=use_xyz,
normalize_xyz=normalize_xyz,
return_grouped_xyz=grouper_return_grouped_xyz,
return_grouped_idx=grouper_return_grouped_idx,
)
else:
grouper = GroupAll(use_xyz)
self.groupers.append(grouper)
def _sample_points(self, points_xyz, features, indices, target_xyz):
"""Perform point sampling based on inputs.
If `indices` is specified, directly sample corresponding points.
Else if `target_xyz` is specified, use is as sampled points.
Otherwise sample points using `self.points_sampler`.
Args:
points_xyz (Tensor): (B, N, 3) xyz coordinates of the features.
features (Tensor): (B, C, N) features of each point.
Default: None.
indices (Tensor): (B, num_point) Index of the features.
Default: None.
target_xyz (Tensor): (B, M, 3) new_xyz coordinates of the outputs.
Returns:
Tensor: (B, num_point, 3) sampled xyz coordinates of points.
Tensor: (B, num_point) sampled points' index.
"""
xyz_flipped = points_xyz.transpose(1, 2).contiguous()
if indices is not None:
assert indices.shape[1] == self.num_point[0]
new_xyz = (
gather_points(xyz_flipped, indices).transpose(1, 2).contiguous()
if self.num_point is not None
else None
)
elif target_xyz is not None:
new_xyz = target_xyz.contiguous()
else:
indices = self.points_sampler(points_xyz, features)
new_xyz = (
gather_points(xyz_flipped, indices).transpose(1, 2).contiguous()
if self.num_point is not None
else None
)
return new_xyz, indices
def _pool_features(self, features):
"""Perform feature aggregation using pooling operation.
Args:
features (torch.Tensor): (B, C, N, K)
Features of locally grouped points before pooling.
Returns:
torch.Tensor: (B, C, N)
Pooled features aggregating local information.
"""
if self.pool_mod == "max":
# (B, C, N, 1)
new_features = F.max_pool2d(features, kernel_size=[1, features.size(3)])
elif self.pool_mod == "avg":
# (B, C, N, 1)
new_features = F.avg_pool2d(features, kernel_size=[1, features.size(3)])
else:
raise NotImplementedError
return new_features.squeeze(-1).contiguous()
def forward(
self,
points_xyz,
features=None,
indices=None,
target_xyz=None,
):
"""forward.
Args:
points_xyz (Tensor): (B, N, 3) xyz coordinates of the features.
features (Tensor): (B, C, N) features of each point.
Default: None.
indices (Tensor): (B, num_point) Index of the features.
Default: None.
target_xyz (Tensor): (B, M, 3) new_xyz coordinates of the outputs.
Returns:
Tensor: (B, M, 3) where M is the number of points.
New features xyz.
Tensor: (B, M, sum_k(mlps[k][-1])) where M is the number
of points. New feature descriptors.
Tensor: (B, M) where M is the number of points.
Index of the features.
"""
new_features_list = []
# sample points, (B, num_point, 3), (B, num_point)
new_xyz, indices = self._sample_points(points_xyz, features, indices, target_xyz)
for i in range(len(self.groupers)):
# grouped_results may contain:
# - grouped_features: (B, C, num_point, nsample)
# - grouped_xyz: (B, 3, num_point, nsample)
# - grouped_idx: (B, num_point, nsample)
grouped_results = self.groupers[i](points_xyz, new_xyz, features)
# (B, mlp[-1], num_point, nsample)
new_features = self.mlps[i](grouped_results)
# this is a bit hack because PAConv outputs two values
# we take the first one as feature
if isinstance(self.mlps[i][0], PAConv):
assert isinstance(new_features, tuple)
new_features = new_features[0]
# (B, mlp[-1], num_point)
new_features = self._pool_features(new_features)
new_features_list.append(new_features)
return new_xyz, torch.cat(new_features_list, dim=1), indices
@SA_MODULES.register_module()
class PointSAModuleMSG(BasePointSAModule):
"""Point set abstraction module with multi-scale grouping (MSG) used in
PointNets.
Args:
num_point (int): Number of points.
radii (list[float]): List of radius in each ball query.
sample_nums (list[int]): Number of samples in each ball query.
mlp_channels (list[list[int]]): Specify of the pointnet before
the global pooling for each scale.
fps_mod (list[str]: Type of FPS method, valid mod
['F-FPS', 'D-FPS', 'FS'], Default: ['D-FPS'].
F-FPS: using feature distances for FPS.
D-FPS: using Euclidean distances of points for FPS.
FS: using F-FPS and D-FPS simultaneously.
fps_sample_range_list (list[int]): Range of points to apply FPS.
Default: [-1].
dilated_group (bool): Whether to use dilated ball query.
Default: False.
norm_cfg (dict): Type of normalization method.
Default: dict(type='BN2d').
use_xyz (bool): Whether to use xyz.
Default: True.
pool_mod (str): Type of pooling method.
Default: 'max_pool'.
normalize_xyz (bool): Whether to normalize local XYZ with radius.
Default: False.
bias (bool | str): If specified as `auto`, it will be decided by the
norm_cfg. Bias will be set as True if `norm_cfg` is None, otherwise
False. Default: "auto".
"""
def __init__(
self,
num_point,
radii,
sample_nums,
mlp_channels,
fps_mod=["D-FPS"],
fps_sample_range_list=[-1],
dilated_group=False,
norm_cfg=dict(type="BN2d"),
use_xyz=True,
pool_mod="max",
normalize_xyz=False,
bias="auto",
):
super(PointSAModuleMSG, self).__init__(
num_point=num_point,
radii=radii,
sample_nums=sample_nums,
mlp_channels=mlp_channels,
fps_mod=fps_mod,
fps_sample_range_list=fps_sample_range_list,
dilated_group=dilated_group,
use_xyz=use_xyz,
pool_mod=pool_mod,
normalize_xyz=normalize_xyz,
)
for i in range(len(self.mlp_channels)):
mlp_channel = self.mlp_channels[i]
if use_xyz:
mlp_channel[0] += 3
mlp = nn.Sequential()
for i in range(len(mlp_channel) - 1):
mlp.add_module(
f"layer{i}",
ConvModule(
mlp_channel[i],
mlp_channel[i + 1],
kernel_size=(1, 1),
stride=(1, 1),
conv_cfg=dict(type="Conv2d"),
norm_cfg=norm_cfg,
bias=bias,
),
)
self.mlps.append(mlp)
@SA_MODULES.register_module()
class PointSAModule(PointSAModuleMSG):
"""Point set abstraction module with single-scale grouping (SSG) used in
PointNets.
Args:
mlp_channels (list[int]): Specify of the pointnet before
the global pooling for each scale.
num_point (int): Number of points.
Default: None.
radius (float): Radius to group with.
Default: None.
num_sample (int): Number of samples in each ball query.
Default: None.
norm_cfg (dict): Type of normalization method.
Default: dict(type='BN2d').
use_xyz (bool): Whether to use xyz.
Default: True.
pool_mod (str): Type of pooling method.
Default: 'max_pool'.
fps_mod (list[str]: Type of FPS method, valid mod
['F-FPS', 'D-FPS', 'FS'], Default: ['D-FPS'].
fps_sample_range_list (list[int]): Range of points to apply FPS.
Default: [-1].
normalize_xyz (bool): Whether to normalize local XYZ with radius.
Default: False.
"""
def __init__(
self,
mlp_channels,
num_point=None,
radius=None,
num_sample=None,
norm_cfg=dict(type="BN2d"),
use_xyz=True,
pool_mod="max",
fps_mod=["D-FPS"],
fps_sample_range_list=[-1],
normalize_xyz=False,
):
super(PointSAModule, self).__init__(
mlp_channels=[mlp_channels],
num_point=num_point,
radii=[radius],
sample_nums=[num_sample],
norm_cfg=norm_cfg,
use_xyz=use_xyz,
pool_mod=pool_mod,
fps_mod=fps_mod,
fps_sample_range_list=fps_sample_range_list,
normalize_xyz=normalize_xyz,
)