2024-10-09 16:13:22 +00:00

519 lines
17 KiB
Python
Executable File

# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
''' Pointnet2 layers.
Modified based on: https://github.com/erikwijmans/Pointnet2_PyTorch
Extended with the following:
1. Uniform sampling in each local region (sample_uniformly)
2. Return sampled points indices to support votenet.
'''
import torch
import torch.nn as nn
import torch.nn.functional as F
import os
import sys
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
sys.path.append(BASE_DIR)
import pointnet2_utils
import pytorch_utils as pt_utils
from typing import List
class _PointnetSAModuleBase(nn.Module):
def __init__(self):
super().__init__()
self.npoint = None
self.groupers = None
self.mlps = None
def forward(self, xyz: torch.Tensor,
features: torch.Tensor = None) -> (torch.Tensor, torch.Tensor):
r"""
Parameters
----------
xyz : torch.Tensor
(B, N, 3) tensor of the xyz coordinates of the features
features : torch.Tensor
(B, N, C) tensor of the descriptors of the the features
Returns
-------
new_xyz : torch.Tensor
(B, npoint, 3) tensor of the new features' xyz
new_features : torch.Tensor
(B, npoint, \sum_k(mlps[k][-1])) tensor of the new_features descriptors
"""
new_features_list = []
xyz_flipped = xyz.transpose(1, 2).contiguous()
new_xyz = pointnet2_utils.gather_operation(
xyz_flipped,
pointnet2_utils.furthest_point_sample(xyz, self.npoint)
).transpose(1, 2).contiguous() if self.npoint is not None else None
for i in range(len(self.groupers)):
new_features = self.groupers[i](
xyz, new_xyz, features
) # (B, C, npoint, nsample)
new_features = self.mlps[i](
new_features
) # (B, mlp[-1], npoint, nsample)
new_features = F.max_pool2d(
new_features, kernel_size=[1, new_features.size(3)]
) # (B, mlp[-1], npoint, 1)
new_features = new_features.squeeze(-1) # (B, mlp[-1], npoint)
new_features_list.append(new_features)
return new_xyz, torch.cat(new_features_list, dim=1)
class PointnetSAModuleMSG(_PointnetSAModuleBase):
r"""Pointnet set abstrction layer with multiscale grouping
Parameters
----------
npoint : int
Number of features
radii : list of float32
list of radii to group with
nsamples : list of int32
Number of samples in each ball query
mlps : list of list of int32
Spec of the pointnet before the global max_pool for each scale
bn : bool
Use batchnorm
"""
def __init__(
self,
*,
npoint: int,
radii: List[float],
nsamples: List[int],
mlps: List[List[int]],
bn: bool = True,
use_xyz: bool = True,
sample_uniformly: bool = False
):
super().__init__()
assert len(radii) == len(nsamples) == len(mlps)
self.npoint = npoint
self.groupers = nn.ModuleList()
self.mlps = nn.ModuleList()
for i in range(len(radii)):
radius = radii[i]
nsample = nsamples[i]
self.groupers.append(
pointnet2_utils.QueryAndGroup(radius, nsample, use_xyz=use_xyz, sample_uniformly=sample_uniformly)
if npoint is not None else pointnet2_utils.GroupAll(use_xyz)
)
mlp_spec = mlps[i]
if use_xyz:
mlp_spec[0] += 3
self.mlps.append(pt_utils.SharedMLP(mlp_spec, bn=bn))
class PointnetSAModule(PointnetSAModuleMSG):
r"""Pointnet set abstrction layer
Parameters
----------
npoint : int
Number of features
radius : float
Radius of ball
nsample : int
Number of samples in the ball query
mlp : list
Spec of the pointnet before the global max_pool
bn : bool
Use batchnorm
"""
def __init__(
self,
*,
mlp: List[int],
npoint: int = None,
radius: float = None,
nsample: int = None,
bn: bool = True,
use_xyz: bool = True
):
super().__init__(
mlps=[mlp],
npoint=npoint,
radii=[radius],
nsamples=[nsample],
bn=bn,
use_xyz=use_xyz
)
class PointnetSAModuleVotes(nn.Module):
''' Modified based on _PointnetSAModuleBase and PointnetSAModuleMSG
with extra support for returning point indices for getting their GT votes '''
def __init__(
self,
*,
mlp: List[int],
npoint: int = None,
radius: float = None,
nsample: int = None,
bn: bool = True,
use_xyz: bool = True,
pooling: str = 'max',
sigma: float = None, # for RBF pooling
normalize_xyz: bool = False, # noramlize local XYZ with radius
sample_uniformly: bool = False,
ret_unique_cnt: bool = False
):
super().__init__()
self.npoint = npoint
self.radius = radius
self.nsample = nsample
self.pooling = pooling
self.mlp_module = None
self.use_xyz = use_xyz
self.sigma = sigma
if self.sigma is None:
self.sigma = self.radius/2
self.normalize_xyz = normalize_xyz
self.ret_unique_cnt = ret_unique_cnt
if npoint is not None:
self.grouper = pointnet2_utils.QueryAndGroup(radius, nsample,
use_xyz=use_xyz, ret_grouped_xyz=True, normalize_xyz=normalize_xyz,
sample_uniformly=sample_uniformly, ret_unique_cnt=ret_unique_cnt)
else:
self.grouper = pointnet2_utils.GroupAll(use_xyz, ret_grouped_xyz=True)
mlp_spec = mlp
if use_xyz and len(mlp_spec)>0:
mlp_spec[0] += 3
self.mlp_module = pt_utils.SharedMLP(mlp_spec, bn=bn)
def forward(self, xyz: torch.Tensor,
features: torch.Tensor = None,
inds: torch.Tensor = None) -> (torch.Tensor, torch.Tensor):
r"""
Parameters
----------
xyz : torch.Tensor
(B, N, 3) tensor of the xyz coordinates of the features
features : torch.Tensor
(B, C, N) tensor of the descriptors of the the features
inds : torch.Tensor
(B, npoint) tensor that stores index to the xyz points (values in 0-N-1)
Returns
-------
new_xyz : torch.Tensor
(B, npoint, 3) tensor of the new features' xyz
new_features : torch.Tensor
(B, \sum_k(mlps[k][-1]), npoint) tensor of the new_features descriptors
inds: torch.Tensor
(B, npoint) tensor of the inds
"""
xyz_flipped = xyz.transpose(1, 2).contiguous()
if inds is None:
inds = pointnet2_utils.furthest_point_sample(xyz, self.npoint)
else:
assert(inds.shape[1] == self.npoint)
new_xyz = pointnet2_utils.gather_operation(
xyz_flipped, inds
).transpose(1, 2).contiguous() if self.npoint is not None else None
if not self.ret_unique_cnt:
grouped_features, grouped_xyz = self.grouper(
xyz, new_xyz, features
) # (B, C, npoint, nsample)
else:
grouped_features, grouped_xyz, unique_cnt = self.grouper(
xyz, new_xyz, features
) # (B, C, npoint, nsample), (B,3,npoint,nsample), (B,npoint)
new_features = self.mlp_module(
grouped_features
) # (B, mlp[-1], npoint, nsample)
if self.pooling == 'max':
new_features = F.max_pool2d(
new_features, kernel_size=[1, new_features.size(3)]
) # (B, mlp[-1], npoint, 1)
elif self.pooling == 'avg':
new_features = F.avg_pool2d(
new_features, kernel_size=[1, new_features.size(3)]
) # (B, mlp[-1], npoint, 1)
elif self.pooling == 'rbf':
# Use radial basis function kernel for weighted sum of features (normalized by nsample and sigma)
# Ref: https://en.wikipedia.org/wiki/Radial_basis_function_kernel
rbf = torch.exp(-1 * grouped_xyz.pow(2).sum(1,keepdim=False) / (self.sigma**2) / 2) # (B, npoint, nsample)
new_features = torch.sum(new_features * rbf.unsqueeze(1), -1, keepdim=True) / float(self.nsample) # (B, mlp[-1], npoint, 1)
new_features = new_features.squeeze(-1) # (B, mlp[-1], npoint)
if not self.ret_unique_cnt:
return new_xyz, new_features, inds
else:
return new_xyz, new_features, inds, unique_cnt
class PointnetSAModuleMSGVotes(nn.Module):
''' Modified based on _PointnetSAModuleBase and PointnetSAModuleMSG
with extra support for returning point indices for getting their GT votes '''
def __init__(
self,
*,
mlps: List[List[int]],
npoint: int,
radii: List[float],
nsamples: List[int],
bn: bool = True,
use_xyz: bool = True,
sample_uniformly: bool = False
):
super().__init__()
assert(len(mlps) == len(nsamples) == len(radii))
self.npoint = npoint
self.groupers = nn.ModuleList()
self.mlps = nn.ModuleList()
for i in range(len(radii)):
radius = radii[i]
nsample = nsamples[i]
self.groupers.append(
pointnet2_utils.QueryAndGroup(radius, nsample, use_xyz=use_xyz, sample_uniformly=sample_uniformly)
if npoint is not None else pointnet2_utils.GroupAll(use_xyz)
)
mlp_spec = mlps[i]
if use_xyz:
mlp_spec[0] += 3
self.mlps.append(pt_utils.SharedMLP(mlp_spec, bn=bn))
def forward(self, xyz: torch.Tensor,
features: torch.Tensor = None, inds: torch.Tensor = None) -> (torch.Tensor, torch.Tensor):
r"""
Parameters
----------
xyz : torch.Tensor
(B, N, 3) tensor of the xyz coordinates of the features
features : torch.Tensor
(B, C, C) tensor of the descriptors of the the features
inds : torch.Tensor
(B, npoint) tensor that stores index to the xyz points (values in 0-N-1)
Returns
-------
new_xyz : torch.Tensor
(B, npoint, 3) tensor of the new features' xyz
new_features : torch.Tensor
(B, \sum_k(mlps[k][-1]), npoint) tensor of the new_features descriptors
inds: torch.Tensor
(B, npoint) tensor of the inds
"""
new_features_list = []
xyz_flipped = xyz.transpose(1, 2).contiguous()
if inds is None:
inds = pointnet2_utils.furthest_point_sample(xyz, self.npoint)
new_xyz = pointnet2_utils.gather_operation(
xyz_flipped, inds
).transpose(1, 2).contiguous() if self.npoint is not None else None
for i in range(len(self.groupers)):
new_features = self.groupers[i](
xyz, new_xyz, features
) # (B, C, npoint, nsample)
new_features = self.mlps[i](
new_features
) # (B, mlp[-1], npoint, nsample)
new_features = F.max_pool2d(
new_features, kernel_size=[1, new_features.size(3)]
) # (B, mlp[-1], npoint, 1)
new_features = new_features.squeeze(-1) # (B, mlp[-1], npoint)
new_features_list.append(new_features)
return new_xyz, torch.cat(new_features_list, dim=1), inds
class PointnetFPModule(nn.Module):
r"""Propigates the features of one set to another
Parameters
----------
mlp : list
Pointnet module parameters
bn : bool
Use batchnorm
"""
def __init__(self, *, mlp: List[int], bn: bool = True):
super().__init__()
self.mlp = pt_utils.SharedMLP(mlp, bn=bn)
def forward(
self, unknown: torch.Tensor, known: torch.Tensor,
unknow_feats: torch.Tensor, known_feats: torch.Tensor
) -> torch.Tensor:
r"""
Parameters
----------
unknown : torch.Tensor
(B, n, 3) tensor of the xyz positions of the unknown features
known : torch.Tensor
(B, m, 3) tensor of the xyz positions of the known features
unknow_feats : torch.Tensor
(B, C1, n) tensor of the features to be propigated to
known_feats : torch.Tensor
(B, C2, m) tensor of features to be propigated
Returns
-------
new_features : torch.Tensor
(B, mlp[-1], n) tensor of the features of the unknown features
"""
if known is not None:
dist, idx = pointnet2_utils.three_nn(unknown, known)
dist_recip = 1.0 / (dist + 1e-8)
norm = torch.sum(dist_recip, dim=2, keepdim=True)
weight = dist_recip / norm
interpolated_feats = pointnet2_utils.three_interpolate(
known_feats, idx, weight
)
else:
interpolated_feats = known_feats.expand(
*known_feats.size()[0:2], unknown.size(1)
)
if unknow_feats is not None:
new_features = torch.cat([interpolated_feats, unknow_feats],
dim=1) #(B, C2 + C1, n)
else:
new_features = interpolated_feats
new_features = new_features.unsqueeze(-1)
new_features = self.mlp(new_features)
return new_features.squeeze(-1)
class PointnetLFPModuleMSG(nn.Module):
''' Modified based on _PointnetSAModuleBase and PointnetSAModuleMSG
learnable feature propagation layer.'''
def __init__(
self,
*,
mlps: List[List[int]],
radii: List[float],
nsamples: List[int],
post_mlp: List[int],
bn: bool = True,
use_xyz: bool = True,
sample_uniformly: bool = False
):
super().__init__()
assert(len(mlps) == len(nsamples) == len(radii))
self.post_mlp = pt_utils.SharedMLP(post_mlp, bn=bn)
self.groupers = nn.ModuleList()
self.mlps = nn.ModuleList()
for i in range(len(radii)):
radius = radii[i]
nsample = nsamples[i]
self.groupers.append(
pointnet2_utils.QueryAndGroup(radius, nsample, use_xyz=use_xyz,
sample_uniformly=sample_uniformly)
)
mlp_spec = mlps[i]
if use_xyz:
mlp_spec[0] += 3
self.mlps.append(pt_utils.SharedMLP(mlp_spec, bn=bn))
def forward(self, xyz2: torch.Tensor, xyz1: torch.Tensor,
features2: torch.Tensor, features1: torch.Tensor) -> torch.Tensor:
r""" Propagate features from xyz1 to xyz2.
Parameters
----------
xyz2 : torch.Tensor
(B, N2, 3) tensor of the xyz coordinates of the features
xyz1 : torch.Tensor
(B, N1, 3) tensor of the xyz coordinates of the features
features2 : torch.Tensor
(B, C2, N2) tensor of the descriptors of the the features
features1 : torch.Tensor
(B, C1, N1) tensor of the descriptors of the the features
Returns
-------
new_features1 : torch.Tensor
(B, \sum_k(mlps[k][-1]), N1) tensor of the new_features descriptors
"""
new_features_list = []
for i in range(len(self.groupers)):
new_features = self.groupers[i](
xyz1, xyz2, features1
) # (B, C1, N2, nsample)
new_features = self.mlps[i](
new_features
) # (B, mlp[-1], N2, nsample)
new_features = F.max_pool2d(
new_features, kernel_size=[1, new_features.size(3)]
) # (B, mlp[-1], N2, 1)
new_features = new_features.squeeze(-1) # (B, mlp[-1], N2)
if features2 is not None:
new_features = torch.cat([new_features, features2],
dim=1) #(B, mlp[-1] + C2, N2)
new_features = new_features.unsqueeze(-1)
new_features = self.post_mlp(new_features)
new_features_list.append(new_features)
return torch.cat(new_features_list, dim=1).squeeze(-1)
if __name__ == "__main__":
from torch.autograd import Variable
torch.manual_seed(1)
torch.cuda.manual_seed_all(1)
xyz = Variable(torch.randn(2, 9, 3).cuda(), requires_grad=True)
xyz_feats = Variable(torch.randn(2, 9, 6).cuda(), requires_grad=True)
test_module = PointnetSAModuleMSG(
npoint=2, radii=[5.0, 10.0], nsamples=[6, 3], mlps=[[9, 3], [9, 6]]
)
test_module.cuda()
print(test_module(xyz, xyz_feats))
for _ in range(1):
_, new_features = test_module(xyz, xyz_feats)
new_features.backward(
torch.cuda.FloatTensor(*new_features.size()).fill_(1)
)
print(new_features)
print(xyz.grad)