Updates and some refactoring

This commit is contained in:
erikwijmans
2017-12-26 19:49:52 -05:00
parent dc4e2b0db3
commit 803d7e1fc6
10 changed files with 211 additions and 226 deletions
+103 -66
View File
@@ -1,96 +1,133 @@
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch.autograd import Variable
import os, sys
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
sys.path.append(BASE_DIR)
sys.path.append(os.path.join(BASE_DIR, "..", "utils"))
sys.path.append(os.path.join(BASE_DIR, "../utils"))
import torch
import torch.nn as nn
from torch.autograd import Variable
import pytorch_utils as pt_utils
from TransformNets import TransformNet, TranslationNet
from pointnet2_modules import PointnetSAModule, PointnetFPModule, PointnetSAModuleMSG
from pointnet2_utils import RandomDropout
from collections import namedtuple
def model_fn_decorator(criterion):
transform_reg = 1e-3
ModelReturn = namedtuple("ModelReturn", ['preds', 'loss', 'acc'])
def ortho_loss(matrix):
return torch.dist(
matrix.bmm(matrix.transpose(1, 2)),
Variable(
torch.eye(matrix.size(1), matrix.size(2)).type(
torch.cuda.FloatTensor)))
def model_fn(model, data, epoch=0, eval=False):
inputs, labels = data
inputs = Variable(inputs.cuda(async=True), volatile=eval)
labels = Variable(labels.cuda(async=True), volatile=eval)
def wrapped(model, inputs, labels):
labels = labels.squeeze()
preds, end_points = model(inputs)
xyz = inputs[..., :3]
if inputs.size(2) > 3:
points = inputs[..., 3:]
else:
points = None
transform_loss = 0.0
for _, T in end_points.items():
transform_loss += ortho_loss(T)
preds = model(xyz, points)
labels = labels.view(-1)
loss = criterion(preds, labels)
preds_loss = criterion(preds, labels)
loss = preds_loss + transform_reg * transform_loss
_, classes = torch.max(preds.data, -1)
acc = (classes == labels.data).sum() / labels.numel()
_, classes = torch.max(preds, 1)
acc = (classes == labels).sum()
return ModelReturn(preds, loss, {"acc": acc})
return preds, loss, acc.data[0]
return wrapped
return model_fn
class PointnetCls(nn.Module):
def __init__(self):
class Pointnet2SSG(nn.Module):
def __init__(self, num_classes, input_channels=9):
super().__init__()
self.translation_net = TranslationNet()
self.t_net = TransformNet(1, 3, 3, scale=False)
self.f_net = TransformNet(64, 1, 64, scale=False)
self.SA_modules = nn.ModuleList()
self.SA_modules.append(
PointnetSAModule(
npoint=512,
radius=0.2,
nsample=64,
mlp=[input_channels, 64, 64, 128]))
self.SA_modules.append(
PointnetSAModule(
npoint=128,
radius=0.4,
nsample=64,
mlp=[128 + 3, 128, 128, 256]))
self.SA_modules.append(PointnetSAModule(mlp=[256 + 3, 256, 512, 1024]))
self.input_mlp = nn.Sequential(
pt_utils.Conv2d(1, 64, [1, 3], bn=True),
pt_utils.Conv2d(64, 64, bn=True))
self.second_mlp = pt_utils.SharedMLP([64, 64, 128, 1024], bn=True)
self.final_mlp = nn.Sequential(
self.FC_layer = nn.Sequential(
pt_utils.FC(1024, 512, bn=True),
nn.Dropout(p=0.5),
pt_utils.FC(512, 256, bn=True),
nn.Dropout(0.3), pt_utils.FC(256, 40, activation=None))
nn.Dropout(p=0.5),
pt_utils.FC(256, num_classes, activation=None))
def forward(self, points: torch.Tensor):
batch_size, n_points, _ = points.size()
end_points = {}
def forward(self, xyz, points=None):
for module in self.SA_modules:
xyz, points = module(xyz, points)
points = points + self.translation_net(points).unsqueeze(1)
points, transform = self.apply_transform(
points, *self.t_net(points.unsqueeze(1)))
points = self.input_mlp(points.unsqueeze(1))
points, transform = self.apply_transform(points.squeeze().transpose(
1, 2), *self.f_net(points))
end_points['trans2'] = transform
points = F.max_pool2d(
self.second_mlp(points.transpose(1, 2).unsqueeze(-1)),
kernel_size=[n_points, 1])
return self.final_mlp(points.view(-1, 1024)), end_points
return self.FC_layer(points.squeeze(1))
def apply_transform(self, points, rotation, scale=None):
points = points @ rotation
if scale is not None:
points = points * scale.contiguous().view(-1, 1, 1).repeat(
1, points.size(1), points.size(2))
class Pointnet2MSG(nn.Module):
def __init__(self, num_classes, input_channels=9):
super().__init__()
return points, rotation
self.SA_modules = nn.ModuleList()
self.SA_modules.append(
PointnetSAModuleMSG(
npoint=512,
radii=[0.1, 0.2, 0.4],
nsamples=[32, 64, 128],
mlps=[[input_channels, 32, 32,
64], [input_channels, 64, 64, 128],
[input_channels, 64, 96, 128]]))
input_channels = 64 + 128 + 128 + 3
self.SA_modules.append(
PointnetSAModuleMSG(
npoint=128,
radii=[0.2, 0.4, 0.8],
nsamples=[16, 32, 64],
mlps=[[input_channels, 64, 64,
128], [input_channels, 128, 128, 256],
[input_channels, 128, 128, 256]]))
self.SA_modules.append(
PointnetSAModule(mlp=[128 + 256 + 256 + 3, 256, 512, 1024]))
self.FC_layer = nn.Sequential(
pt_utils.FC(1024, 512, bn=True),
nn.Dropout(p=0.5),
pt_utils.FC(512, 256, bn=True),
nn.Dropout(p=0.5),
pt_utils.FC(256, num_classes, activation=None))
def forward(self, xyz, points=None):
for module in self.SA_modules:
xyz, points = module(xyz, points)
return self.FC_layer(points.squeeze(1))
if __name__ == "__main__":
from torch.autograd import Variable
model = PointnetCls()
data = Variable(torch.randn(2, 10, 3))
print(model(data))
import numpy as np
import torch.optim as optim
B = 2
N = 32
inputs = torch.randn(B, N, 9).cuda()
labels = torch.from_numpy(np.random.randint(0, 3, size=B)).cuda()
model = Pointnet2SSG(3)
model.cuda()
optimizer = optim.Adam(model.parameters(), lr=1e-2)
model_fn = model_fn_decorator(nn.CrossEntropyLoss())
for _ in range(20):
optimizer.zero_grad()
_, loss, _ = model_fn(model, (inputs, labels))
loss.backward()
print(loss.data[0])
optimizer.step()
+78 -63
View File
@@ -43,22 +43,34 @@ class Pointnet2SSG(nn.Module):
self.initial_dropout = RandomDropout(0.4)
self.SA_module0 = PointnetSAModule(
npoint=1024,
radius=0.1,
nsample=32,
mlp=[input_channels, 32, 32, 64])
self.SA_module1 = PointnetSAModule(
npoint=256, radius=0.2, nsample=32, mlp=[64 + 3, 64, 64, 128])
self.SA_module2 = PointnetSAModule(
npoint=64, radius=0.4, nsample=32, mlp=[128 + 3, 128, 128, 256])
self.SA_module3 = PointnetSAModule(
npoint=16, radius=0.8, nsample=32, mlp=[256 + 3, 256, 256, 512])
self.SA_modules = nn.ModuleList()
self.SA_modules.append(
PointnetSAModule(
npoint=1024,
radius=0.1,
nsample=32,
mlp=[input_channels, 32, 32, 64]))
self.SA_modules.append(
PointnetSAModule(
npoint=256, radius=0.2, nsample=32, mlp=[64 + 3, 64, 64, 128]))
self.SA_modules.append(
PointnetSAModule(
npoint=64,
radius=0.4,
nsample=32,
mlp=[128 + 3, 128, 128, 256]))
self.SA_modules.append(
PointnetSAModule(
npoint=16,
radius=0.8,
nsample=32,
mlp=[256 + 3, 256, 256, 512]))
self.FP_module0 = PointnetFPModule(mlp=[512 + 256, 256, 256])
self.FP_module1 = PointnetFPModule(mlp=[256 + 128, 256, 256])
self.FP_module2 = PointnetFPModule(mlp=[256 + 64, 256, 128])
self.FP_module3 = PointnetFPModule(mlp=[128 + 6, 128, 128, 128])
self.FP_modules = nn.ModuleList()
self.FP_modules.append(PointnetFPModule(mlp=[128 + input_channels - 3, 128, 128, 128]))
self.FP_modules.append(PointnetFPModule(mlp=[256 + 64, 256, 128]))
self.FP_modules.append(PointnetFPModule(mlp=[256 + 128, 256, 256]))
self.FP_modules.append(PointnetFPModule(mlp=[512 + 256, 256, 256]))
self.FC_layer = nn.Sequential(
pt_utils.Conv1d(128, 128, bn=True), nn.Dropout(),
@@ -72,18 +84,17 @@ class Pointnet2SSG(nn.Module):
l0_xyz = self.initial_dropout(xyz)
l0_points = None
l1_xyz, l1_points = self.SA_module0(l0_xyz, l0_points)
l2_xyz, l2_points = self.SA_module1(l1_xyz, l1_points)
l3_xyz, l3_points = self.SA_module2(l2_xyz, l2_points)
l4_xyz, l4_points = self.SA_module3(l3_xyz, l3_points)
l_xyz, l_points = [l0_xyz], [l0_points]
for i in range(len(self.SA_modules)):
li_xyz, li_points = self.SA_modules[i](l_xyz[i], l_points[i])
l_xyz.append(li_xyz)
l_points.append(li_points)
l3_points = self.FP_module0(l3_xyz, l4_xyz, l3_points, l4_points)
l2_points = self.FP_module1(l2_xyz, l3_xyz, l2_points, l3_points)
l1_points = self.FP_module2(l1_xyz, l2_xyz, l1_points, l2_points)
l0_points = self.FP_module3(l0_xyz, l1_xyz, l0_points,
l1_points).transpose(1, 2)
for i in range(-1, -(len(self.FP_modules + 1) - 1), -1):
l_points[i - 1] = self.FP_modules[i](l_xyz[i - 1], l_xyz[i],
l_points[i - 1], l_points[i])
return self.FC_layer(l0_points).transpose(1, 2).contiguous()
return self.FC_layer(l_points[0].transpose(1, 2)).transpose(1, 2).contiguous()
class Pointnet2MSG(nn.Module):
@@ -93,43 +104,50 @@ class Pointnet2MSG(nn.Module):
self.initial_dropout = RandomDropout(0.95, inplace=True)
self.initial_dropout = None
self.SA_modules = nn.ModuleList()
c_in = input_channels
self.SA_module0 = PointnetSAModuleMSG(
npoint=1024,
radii=[0.05, 0.1],
nsamples=[16, 32],
mlps=[[c_in, 16, 16, 32], [c_in, 32, 32, 64]])
self.SA_modules.append(
PointnetSAModuleMSG(
npoint=1024,
radii=[0.05, 0.1],
nsamples=[16, 32],
mlps=[[c_in, 16, 16, 32], [c_in, 32, 32, 64]]))
c_out_0 = 32 + 64
c_in = c_out_0 + 3
self.SA_module1 = PointnetSAModuleMSG(
npoint=256,
radii=[0.1, 0.2],
nsamples=[16, 32],
mlps=[[c_in, 64, 64, 128], [c_in, 64, 96, 128]])
self.SA_modules.append(
PointnetSAModuleMSG(
npoint=256,
radii=[0.1, 0.2],
nsamples=[16, 32],
mlps=[[c_in, 64, 64, 128], [c_in, 64, 96, 128]]))
c_out_1 = 128 + 128
c_in = c_out_1 + 3
self.SA_module2 = PointnetSAModuleMSG(
npoint=64,
radii=[0.2, 0.4],
nsamples=[16, 32],
mlps=[[c_in, 128, 196, 256], [c_in, 128, 196, 256]])
self.SA_modules.append(
PointnetSAModuleMSG(
npoint=64,
radii=[0.2, 0.4],
nsamples=[16, 32],
mlps=[[c_in, 128, 196, 256], [c_in, 128, 196, 256]]))
c_out_2 = 256 + 256
c_in = c_out_2 + 3
self.SA_module3 = PointnetSAModuleMSG(
npoint=16,
radii=[0.4, 0.8],
nsamples=[16, 32],
mlps=[[c_in, 256, 256, 512], [c_in, 256, 384, 512]])
self.SA_modules.append(
PointnetSAModuleMSG(
npoint=16,
radii=[0.4, 0.8],
nsamples=[16, 32],
mlps=[[c_in, 256, 256, 512], [c_in, 256, 384, 512]]))
c_out_3 = 512 + 512
self.FP_module3 = PointnetFPModule(mlp=[c_out_3 + c_out_2, 512, 512])
self.FP_module2 = PointnetFPModule(mlp=[512 + c_out_1, 512, 512])
self.FP_module1 = PointnetFPModule(mlp=[512 + c_out_0, 256, 256])
self.FP_module0 = PointnetFPModule(
mlp=[256 + input_channels - 3, 128, 128])
self.FP_modules = nn.ModuleList()
self.FP_modules.append(
PointnetFPModule(mlp=[256 + input_channels - 3, 128, 128]))
self.FP_modules.append(PointnetFPModule(mlp=[512 + c_out_0, 256, 256]))
self.FP_modules.append(PointnetFPModule(mlp=[512 + c_out_1, 512, 512]))
self.FP_modules.append(
PointnetFPModule(mlp=[c_out_3 + c_out_2, 512, 512]))
self.FC_layer = nn.Sequential(
pt_utils.Conv1d(128, 128, bn=True), nn.Dropout(),
@@ -142,20 +160,17 @@ class Pointnet2MSG(nn.Module):
elif self.initial_dropout is not None:
xyz = self.initial_dropout(xyz)
l0_xyz, l0_points = xyz, points
l_xyz, l_points = [xyz], [points]
for i in range(len(self.SA_modules)):
li_xyz, li_points = self.SA_modules[i](l_xyz[i], l_points[i])
l_xyz.append(li_xyz)
l_points.append(li_points)
l1_xyz, l1_points = self.SA_module0(l0_xyz, l0_points)
l2_xyz, l2_points = self.SA_module1(l1_xyz, l1_points)
l3_xyz, l3_points = self.SA_module2(l2_xyz, l2_points)
l4_xyz, l4_points = self.SA_module3(l3_xyz, l3_points)
for i in range(-1, -(len(self.FP_modules) + 1), -1):
l_points[i - 1] = self.FP_modules[i](l_xyz[i - 1], l_xyz[i],
l_points[i - 1], l_points[i])
l3_points = self.FP_module3(l3_xyz, l4_xyz, l3_points, l4_points)
l2_points = self.FP_module2(l2_xyz, l3_xyz, l2_points, l3_points)
l1_points = self.FP_module1(l1_xyz, l2_xyz, l1_points, l2_points)
l0_points = self.FP_module0(l0_xyz, l1_xyz, l0_points,
l1_points).transpose(1, 2)
return self.FC_layer(l0_points).transpose(1, 2).contiguous()
return self.FC_layer(l_points[0].transpose(1, 2)).transpose(1, 2).contiguous()
if __name__ == "__main__":
@@ -170,7 +185,7 @@ if __name__ == "__main__":
model = Pointnet2MSG(3)
model.cuda()
optimizer = optim.Adam(model.parameters(), lr=1e-5)
optimizer = optim.Adam(model.parameters(), lr=1e-2)
model_fn = model_fn_decorator(nn.CrossEntropyLoss())
for _ in range(20):
-75
View File
@@ -1,75 +0,0 @@
import torch
import torch.nn as nn
from torch.autograd import Variable
import torch.nn.functional as F
import os, sys
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
sys.path.append(BASE_DIR)
import pytorch_utils as pt_utils
class TransformNet(nn.Module):
def __init__(self, in_size, channels, K, scale=False):
super().__init__()
self.K, self.scale = K, scale
self.convs = nn.Sequential()
self.convs.add_module('conv0',
pt_utils.Conv2d(
in_size, 64, kernel_size=[1, channels], bn=True))
self.convs.add_module('rest',
pt_utils.SharedMLP([64, 128, 1024], bn=True))
self.fc = nn.Sequential(
pt_utils.FC(1024, 512, bn=True), pt_utils.FC(512, 256, bn=True))
outsize = K * K
if scale:
outsize += 1
self.final_W = nn.Parameter(torch.FloatTensor(256, outsize))
self.final_b = nn.Parameter(torch.FloatTensor(outsize))
self.init_weights()
def forward(self, X):
X = self.convs(X)
X = F.adaptive_max_pool2d(X, [1, 1])
X = self.fc(X.view(-1, 1024))
X = X @ self.final_W + self.final_b
rotation = X[:, 0:self.K * self.K].contiguous().view(
-1, self.K, self.K)
if not self.scale:
return rotation, None
scale = X[:, -1].contiguous()
return rotation, scale
def init_weights(self):
torch.nn.init.constant(self.final_W, 0)
self.final_b.data[:self.K * self.K] = (torch.eye(
self.K, self.K) + 1e-1 * torch.randn(self.K, self.K)).view(-1)
if self.scale:
self.final_b.data[-1] = 1.0
class TranslationNet(nn.Module):
def forward(self, X):
return -torch.mean(X, dim=1)
if __name__ == "__main__":
from torch.autograd import Variable
net = TransformNet(5, 1, 3, True)
net.init_weights()
data = Variable(torch.FloatTensor(1, 5, 10, 1))
print(net(data))
net = TranslationNet(5, 1, 3)
net.init_weights()
print(net(data))
+5 -1
View File
@@ -1 +1,5 @@
from .Pointnet2SemSeg import Pointnet2MSG, Pointnet2SSG
from .Pointnet2SemSeg import Pointnet2MSG as Pointnet2SemMSG
from .Pointnet2SemSeg import Pointnet2SSG as Pointnet2SemSSG
from .Pointnet2Cls import Pointnet2MSG as Pointnet2ClsMSG
from .Pointnet2Cls import Pointnet2SSG as Pointnet2ClsSSG
+17 -16
View File
@@ -9,49 +9,51 @@ from torchvision import transforms
import os
import tensorboard_logger as tb_log
from models import PointnetCls as Pointnet
from models.PointnetCls import model_fn_decorator
from models import Pointnet2ClsMSG as Pointnet
from models.Pointnet2Cls import model_fn_decorator
from data import ModelNet40Cls
import utils.pytorch_utils as pt_utils
import utils.data_utils as d_utils
import argparse
def parse_args():
parser = argparse.ArgumentParser(description="Arg parser")
parser = argparse.ArgumentParser(
description="Arguments for cls training",
formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument(
"-batch_size", type=int, default=128, help="Batch size [default: 128]")
"-batch_size", type=int, default=16, help="Batch size")
parser.add_argument(
"-num_points",
type=int,
default=1024,
help="Number of points to train with [default: 1024]")
help="Number of points to train with")
parser.add_argument(
"-weight_decay", type=float, default=1e-5, help="L2 regularization coeff")
parser.add_argument(
"-lr",
type=float,
default=1e-2,
help="Initial learning rate [default: 1e-2]")
help="Initial learning rate")
parser.add_argument(
"-lr_decay",
type=float,
default=0.7,
help="Learning rate decay gamma [default: 0.7]")
help="Learning rate decay gamma")
parser.add_argument(
"-decay_step",
type=int,
default=20,
help="Learning rate decay step [default: 20]")
help="Learning rate decay step")
parser.add_argument(
"-bn_momentum",
type=float,
default=0.5,
help="Initial batch norm momentum [default: 0.5]")
help="Initial batch norm momentum")
parser.add_argument(
"-bnm_decay",
type=float,
default=0.5,
help="Batch norm momentum decay gamma [default: 0.5]")
help="Batch norm momentum decay gamma")
parser.add_argument(
"-checkpoint", type=str, default=None, help="Checkpoint to start from")
parser.add_argument(
@@ -74,8 +76,7 @@ if __name__ == "__main__":
transforms = transforms.Compose([
d_utils.PointcloudToTensor(),
d_utils.PointcloudRotate(x_axis=True),
d_utils.PointcloudScale(),
d_utils.PointcloudRotate(x_axis=True, z_axis=True),
d_utils.PointcloudTranslate(),
d_utils.PointcloudJitter()
])
@@ -99,7 +100,7 @@ if __name__ == "__main__":
tb_log.configure('runs/{}'.format(args.run_name))
model = Pointnet()
model = Pointnet(input_channels=3, num_classes=40)
model.cuda()
optimizer = optim.Adam(
model.parameters(), lr=args.lr, weight_decay=args.weight_decay)
@@ -107,7 +108,7 @@ if __name__ == "__main__":
bn_lbmd = lambda e: max(args.bn_momentum * args.bnm_decay**(e // args.decay_step), bnm_clip)
if args.checkpoint is not None:
start_epoch, best_prec = pt_utils.load_checkpoint(
start_epoch, best_loss = pt_utils.load_checkpoint(
model, optimizer, filename=args.checkpoint.split(".")[0])
lr_scheduler = lr_sched.LambdaLR(
@@ -118,7 +119,7 @@ if __name__ == "__main__":
lr_scheduler = lr_sched.LambdaLR(optimizer, lr_lambda=lr_lbmd)
bnm_scheduler = pt_utils.BNMomentumScheduler(model, bn_lambda=bn_lbmd)
best_prec = 0.0
best_loss = 1e10
start_epoch = 1
model_fn = model_fn_decorator(nn.CrossEntropyLoss())
@@ -137,7 +138,7 @@ if __name__ == "__main__":
args.epochs,
train_loader,
test_loader,
best_prec=best_prec)
best_loss=best_loss)
if start_epoch == args.epochs:
_ = trainer.eval_epoch(start_epoch, test_loader)
+1 -1
View File
@@ -9,7 +9,7 @@ import numpy as np
import tensorboard_logger as tb_log
import os
from models import Pointnet2MSG as Pointnet
from models import Pointnet2SSG as Pointnet
from models.Pointnet2SemSeg import model_fn_decorator
from data import Indoor3DSemSeg
import utils.pytorch_utils as pt_utils
+3 -1
View File
@@ -1,7 +1,7 @@
project(PointNet2)
cmake_minimum_required(VERSION 3.5)
find_package(CUDA)
find_package(CUDA REQUIRED)
include_directories("${CMAKE_SOURCE_DIR}/cinclude")
cuda_include_directories("${CMAKE_SOURCE_DIR}/cinclude")
@@ -9,11 +9,13 @@ file(GLOB cuda_kernels_src "csrc/*.cu")
cuda_compile(cuda_kernels SHARED ${cuda_kernels_src} OPTIONS -O3)
file(GLOB wrapper_headers "cinclude/*wrapper.h")
file(GLOB wrapper_sources "csrs/*.c")
add_custom_command(OUTPUT "${CMAKE_SOURCE_DIR}/_ext/__ext.so"
WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
COMMAND python "${CMAKE_SOURCE_DIR}/build_ffi.py" ${cuda_kernels}
DEPENDS ${cuda_kernels}
DEPENDS ${wrapper_headers}
DEPENDS ${wrapper_sources}
VERBATIM)
add_custom_target(ext ALL
+2 -1
View File
@@ -16,7 +16,8 @@ ffi = create_extension(
relative_to=__file__,
with_cuda=True,
extra_objects=extra_objects,
include_dirs=[path.join(base_dir, 'cinclude')])
include_dirs=[path.join(base_dir, 'cinclude')],
verbose=False)
if __name__ == "__main__":
assert torch.cuda.is_available(), "Needs CUDA!"
+1 -1
View File
@@ -16,7 +16,7 @@ class PointcloudScale(object):
class PointcloudRotate(object):
def __init__(self, x_axis=False, z_axis=True):
assert x_axis or z_axis
self.x, self.y = x_axis, z_axis
self.x, self.z = x_axis, z_axis
def _get_angles(self):
rotation_angle = np.random.uniform() * 2 * np.pi
+1 -1
View File
@@ -142,7 +142,7 @@ class PointnetSAModule(nn.Module):
new_xyz = pointnet2_utils.gather_points(
xyz, pointnet2_utils.furthest_point_sample(xyz, self.npoint))
else:
new_xyz = xyz.new([[[0, 0, 0]]]).expand(xyz.size(0), 1, 3)
new_xyz = xyz.data.new([[[0, 0, 0]]]).expand(xyz.size(0), 1, 3)
new_points = self.grouper(xyz, new_xyz,
points) # (B, npoint, nsample, 3 + C)