# Copyright 2020 Division of Medical Image Computing, German Cancer Research Center (DKFZ), Heidelberg, Germany
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from copy import deepcopy
from nnunet.utilities.nd_softmax import softmax_helper
from torch import nn
import torch
import numpy as np
from nnunet.network_architecture.initialization import InitWeights_He
from nnunet.network_architecture.neural_network import SegmentationNetwork
import torch.nn.functional
class ConvDropoutNormNonlin(nn.Module):
"""
fixes a bug in ConvDropoutNormNonlin where lrelu was used regardless of nonlin. Bad.
"""
def __init__(self, input_channels, output_channels,
conv_op=nn.Conv2d, conv_kwargs=None,
norm_op=nn.BatchNorm2d, norm_op_kwargs=None,
dropout_op=nn.Dropout2d, dropout_op_kwargs=None,
nonlin=nn.LeakyReLU, nonlin_kwargs=None):
super(ConvDropoutNormNonlin, self).__init__()
if nonlin_kwargs is None:
nonlin_kwargs = {'negative_slope': 1e-2, 'inplace': True}
if dropout_op_kwargs is None:
dropout_op_kwargs = {'p': 0.5, 'inplace': True}
if norm_op_kwargs is None:
norm_op_kwargs = {'eps': 1e-5, 'affine': True, 'momentum': 0.1}
if conv_kwargs is None:
conv_kwargs = {'kernel_size': 3, 'stride': 1, 'padding': 1, 'dilation': 1, 'bias': True}
self.nonlin_kwargs = nonlin_kwargs
self.nonlin = nonlin
self.dropout_op = dropout_op
self.dropout_op_kwargs = dropout_op_kwargs
self.norm_op_kwargs = norm_op_kwargs
self.conv_kwargs = conv_kwargs
self.conv_op = conv_op
self.norm_op = norm_op
self.conv = self.conv_op(input_channels, output_channels, **self.conv_kwargs)
if self.dropout_op is not None and self.dropout_op_kwargs['p'] is not None and self.dropout_op_kwargs[
'p'] > 0:
self.dropout = self.dropout_op(**self.dropout_op_kwargs)
else:
self.dropout = None
self.instnorm = self.norm_op(output_channels, **self.norm_op_kwargs)
self.lrelu = self.nonlin(**self.nonlin_kwargs)
def forward(self, x):
x = self.conv(x)
if self.dropout is not None:
x = self.dropout(x)
return self.lrelu(self.instnorm(x))
class ConvDropoutNonlinNorm(ConvDropoutNormNonlin):
def forward(self, x):
x = self.conv(x)
if self.dropout is not None:
x = self.dropout(x)
return self.instnorm(self.lrelu(x))
class StackedConvLayers(nn.Module):
def __init__(self, input_feature_channels, output_feature_channels, num_convs,
conv_op=nn.Conv2d, conv_kwargs=None,
norm_op=nn.BatchNorm2d, norm_op_kwargs=None,
dropout_op=nn.Dropout2d, dropout_op_kwargs=None,
nonlin=nn.LeakyReLU, nonlin_kwargs=None, first_stride=None, basic_block=ConvDropoutNormNonlin):
'''
stacks ConvDropoutNormLReLU layers. initial_stride will only be applied to first layer in the stack. The other parameters affect all layers
:param input_feature_channels:
:param output_feature_channels:
:param num_convs:
:param dilation:
:param kernel_size:
:param padding:
:param dropout:
:param initial_stride:
:param conv_op:
:param norm_op:
:param dropout_op:
:param inplace:
:param neg_slope:
:param norm_affine:
:param conv_bias:
'''
self.input_channels = input_feature_channels
self.output_channels = output_feature_channels
if nonlin_kwargs is None:
nonlin_kwargs = {'negative_slope': 1e-2, 'inplace': True}
if dropout_op_kwargs is None:
dropout_op_kwargs = {'p': 0.5, 'inplace': True}
if norm_op_kwargs is None:
norm_op_kwargs = {'eps': 1e-5, 'affine': True, 'momentum': 0.1}
if conv_kwargs is None:
conv_kwargs = {'kernel_size': 3, 'stride': 1, 'padding': 1, 'dilation': 1, 'bias': True}
self.nonlin_kwargs = nonlin_kwargs
self.nonlin = nonlin
self.dropout_op = dropout_op
self.dropout_op_kwargs = dropout_op_kwargs
self.norm_op_kwargs = norm_op_kwargs
self.conv_kwargs = conv_kwargs
self.conv_op = conv_op
self.norm_op = norm_op
if first_stride is not None:
self.conv_kwargs_first_conv = deepcopy(conv_kwargs)
self.conv_kwargs_first_conv['stride'] = first_stride
else:
self.conv_kwargs_first_conv = conv_kwargs
super(StackedConvLayers, self).__init__()
self.blocks = nn.Sequential(
*([basic_block(input_feature_channels, output_feature_channels, self.conv_op,
self.conv_kwargs_first_conv,
self.norm_op, self.norm_op_kwargs, self.dropout_op, self.dropout_op_kwargs,
self.nonlin, self.nonlin_kwargs)] +
[basic_block(output_feature_channels, output_feature_channels, self.conv_op,
self.conv_kwargs,
self.norm_op, self.norm_op_kwargs, self.dropout_op, self.dropout_op_kwargs,
self.nonlin, self.nonlin_kwargs) for _ in range(num_convs - 1)]))
def forward(self, x):
return self.blocks(x)
def print_module_training_status(module):
if isinstance(module, nn.Conv2d) or isinstance(module, nn.Conv3d) or isinstance(module, nn.Dropout3d) or \
isinstance(module, nn.Dropout2d) or isinstance(module, nn.Dropout) or isinstance(module, nn.InstanceNorm3d) \
or isinstance(module, nn.InstanceNorm2d) or isinstance(module, nn.InstanceNorm1d) \
or isinstance(module, nn.BatchNorm2d) or isinstance(module, nn.BatchNorm3d) or isinstance(module,
nn.BatchNorm1d):
print(str(module), module.training)
class Upsample(nn.Module):
def __init__(self, size=None, scale_factor=None, mode='nearest', align_corners=False):
super(Upsample, self).__init__()
self.align_corners = align_corners
self.mode = mode
self.scale_factor = scale_factor
self.size = size
def forward(self, x):
return nn.functional.interpolate(x, size=self.size, scale_factor=self.scale_factor, mode=self.mode,
align_corners=self.align_corners)
class Generic_UNet(SegmentationNetwork):
DEFAULT_BATCH_SIZE_3D = 2
DEFAULT_PATCH_SIZE_3D = (64, 192, 160)
SPACING_FACTOR_BETWEEN_STAGES = 2
BASE_NUM_FEATURES_3D = 30
MAX_NUMPOOL_3D = 999
MAX_NUM_FILTERS_3D = 320
DEFAULT_PATCH_SIZE_2D = (256, 256)
BASE_NUM_FEATURES_2D = 30
DEFAULT_BATCH_SIZE_2D = 50
MAX_NUMPOOL_2D = 999
MAX_FILTERS_2D = 480
use_this_for_batch_size_computation_2D = 19739648
use_this_for_batch_size_computation_3D = 520000000 # 505789440
def __init__(self, input_channels, base_num_features, num_classes, num_pool, num_conv_per_stage=2,
feat_map_mul_on_downscale=2, conv_op=nn.Conv2d,
norm_op=nn.BatchNorm2d, norm_op_kwargs=None,
dropout_op=nn.Dropout2d, dropout_op_kwargs=None,
nonlin=nn.LeakyReLU, nonlin_kwargs=None, deep_supervision=True, dropout_in_localization=False,
final_nonlin=softmax_helper, weightInitializer=InitWeights_He(1e-2), pool_op_kernel_sizes=None,
conv_kernel_sizes=None,
upscale_logits=False, convolutional_pooling=False, convolutional_upsampling=False,
max_num_features=None, basic_block=ConvDropoutNormNonlin,
seg_output_use_bias=False):
"""
basically more flexible than v1, architecture is the same
Does this look complicated? Nah bro. Functionality > usability
This does everything you need, including world peace.
Questions? -> f.isensee@dkfz.de
"""
super(Generic_UNet, self).__init__()
self.convolutional_upsampling = convolutional_upsampling
self.convolutional_pooling = convolutional_pooling
self.upscale_logits = upscale_logits
if nonlin_kwargs is None:
nonlin_kwargs = {'negative_slope': 1e-2, 'inplace': True}
if dropout_op_kwargs is None:
dropout_op_kwargs = {'p': 0.5, 'inplace': True}
if norm_op_kwargs is None:
norm_op_kwargs = {'eps': 1e-5, 'affine': True, 'momentum': 0.1}
self.conv_kwargs = {'stride': 1, 'dilation': 1, 'bias': True}
self.nonlin = nonlin
self.nonlin_kwargs = nonlin_kwargs
self.dropout_op_kwargs = dropout_op_kwargs
self.norm_op_kwargs = norm_op_kwargs
self.weightInitializer = weightInitializer
self.conv_op = conv_op
self.norm_op = norm_op
self.dropout_op = dropout_op
self.num_classes = num_classes
self.final_nonlin = final_nonlin
self._deep_supervision = deep_supervision
self.do_ds = deep_supervision
if conv_op == nn.Conv2d:
upsample_mode = 'bilinear'
pool_op = nn.MaxPool2d
transpconv = nn.ConvTranspose2d
if pool_op_kernel_sizes is None:
pool_op_kernel_sizes = [(2, 2)] * num_pool
if conv_kernel_sizes is None:
conv_kernel_sizes = [(3, 3)] * (num_pool + 1)
elif conv_op == nn.Conv3d:
upsample_mode = 'trilinear'
pool_op = nn.MaxPool3d
transpconv = nn.ConvTranspose3d
if pool_op_kernel_sizes is None:
pool_op_kernel_sizes = [(2, 2, 2)] * num_pool
if conv_kernel_sizes is None:
conv_kernel_sizes = [(3, 3, 3)] * (num_pool + 1)
else:
raise ValueError("unknown convolution dimensionality, conv op: %s" % str(conv_op))
self.input_shape_must_be_divisible_by = np.prod(pool_op_kernel_sizes, 0, dtype=np.int64)
self.pool_op_kernel_sizes = pool_op_kernel_sizes
self.conv_kernel_sizes = conv_kernel_sizes
self.conv_pad_sizes = []
for krnl in self.conv_kernel_sizes:
self.conv_pad_sizes.append([1 if i == 3 else 0 for i in krnl])
if max_num_features is None:
if self.conv_op == nn.Conv3d:
self.max_num_features = self.MAX_NUM_FILTERS_3D
else:
self.max_num_features = self.MAX_FILTERS_2D
else:
self.max_num_features = max_num_features
self.conv_blocks_context = []
self.conv_blocks_localization = []
self.td = []
self.tu = []
self.seg_outputs = []
output_features = base_num_features
input_features = input_channels
for d in range(num_pool):
# determine the first stride
if d != 0 and self.convolutional_pooling:
first_stride = pool_op_kernel_sizes[d - 1]
else:
first_stride = None
self.conv_kwargs['kernel_size'] = self.conv_kernel_sizes[d]
self.conv_kwargs['padding'] = self.conv_pad_sizes[d]
# add convolutions
self.conv_blocks_context.append(StackedConvLayers(input_features, output_features, num_conv_per_stage,
self.conv_op, self.conv_kwargs, self.norm_op,
self.norm_op_kwargs, self.dropout_op,
self.dropout_op_kwargs, self.nonlin, self.nonlin_kwargs,
first_stride, basic_block=basic_block))
if not self.convolutional_pooling:
self.td.append(pool_op(pool_op_kernel_sizes[d]))
input_features = output_features
output_features = int(np.round(output_features * feat_map_mul_on_downscale))
output_features = min(output_features, self.max_num_features)
# now the bottleneck.
# determine the first stride
if self.convolutional_pooling:
first_stride = pool_op_kernel_sizes[-1]
else:
first_stride = None
# the output of the last conv must match the number of features from the skip connection if we are not using
# convolutional upsampling. If we use convolutional upsampling then the reduction in feature maps will be
# done by the transposed conv
if self.convolutional_upsampling:
final_num_features = output_features
else:
final_num_features = self.conv_blocks_context[-1].output_channels
self.conv_kwargs['kernel_size'] = self.conv_kernel_sizes[num_pool]
self.conv_kwargs['padding'] = self.conv_pad_sizes[num_pool]
self.conv_blocks_context.append(nn.Sequential(
StackedConvLayers(input_features, output_features, num_conv_per_stage - 1, self.conv_op, self.conv_kwargs,
self.norm_op, self.norm_op_kwargs, self.dropout_op, self.dropout_op_kwargs, self.nonlin,
self.nonlin_kwargs, first_stride, basic_block=basic_block),
StackedConvLayers(output_features, final_num_features, 1, self.conv_op, self.conv_kwargs,
self.norm_op, self.norm_op_kwargs, self.dropout_op, self.dropout_op_kwargs, self.nonlin,
self.nonlin_kwargs, basic_block=basic_block)))
# if we don't want to do dropout in the localization pathway then we set the dropout prob to zero here
if not dropout_in_localization:
old_dropout_p = self.dropout_op_kwargs['p']
self.dropout_op_kwargs['p'] = 0.0
# now lets build the localization pathway
for u in range(num_pool):
nfeatures_from_down = final_num_features
nfeatures_from_skip = self.conv_blocks_context[
-(2 + u)].output_channels # self.conv_blocks_context[-1] is bottleneck, so start with -2
n_features_after_tu_and_concat = nfeatures_from_skip * 2
# the first conv reduces the number of features to match those of skip
# the following convs work on that number of features
# if not convolutional upsampling then the final conv reduces the num of features again
if u != num_pool - 1 and not self.convolutional_upsampling:
final_num_features = self.conv_blocks_context[-(3 + u)].output_channels
else:
final_num_features = nfeatures_from_skip
if not self.convolutional_upsampling:
self.tu.append(Upsample(scale_factor=pool_op_kernel_sizes[-(u + 1)], mode=upsample_mode))
else:
self.tu.append(transpconv(nfeatures_from_down, nfeatures_from_skip, pool_op_kernel_sizes[-(u + 1)],
pool_op_kernel_sizes[-(u + 1)], bias=False))
self.conv_kwargs['kernel_size'] = self.conv_kernel_sizes[- (u + 1)]
self.conv_kwargs['padding'] = self.conv_pad_sizes[- (u + 1)]
self.conv_blocks_localization.append(nn.Sequential(
StackedConvLayers(n_features_after_tu_and_concat, nfeatures_from_skip, num_conv_per_stage - 1,
self.conv_op, self.conv_kwargs, self.norm_op, self.norm_op_kwargs, self.dropout_op,
self.dropout_op_kwargs, self.nonlin, self.nonlin_kwargs, basic_block=basic_block),
StackedConvLayers(nfeatures_from_skip, final_num_features, 1, self.conv_op, self.conv_kwargs,
self.norm_op, self.norm_op_kwargs, self.dropout_op, self.dropout_op_kwargs,
self.nonlin, self.nonlin_kwargs, basic_block=basic_block)
))
for ds in range(len(self.conv_blocks_localization)):
self.seg_outputs.append(conv_op(self.conv_blocks_localization[ds][-1].output_channels, num_classes,
1, 1, 0, 1, 1, seg_output_use_bias))
self.upscale_logits_ops = []
cum_upsample = np.cumprod(np.vstack(pool_op_kernel_sizes), axis=0)[::-1]
for usl in range(num_pool - 1):
if self.upscale_logits:
self.upscale_logits_ops.append(Upsample(scale_factor=tuple([int(i) for i in cum_upsample[usl + 1]]),
mode=upsample_mode))
else:
self.upscale_logits_ops.append(lambda x: x)
if not dropout_in_localization:
self.dropout_op_kwargs['p'] = old_dropout_p
# register all modules properly
self.conv_blocks_localization = nn.ModuleList(self.conv_blocks_localization)
self.conv_blocks_context = nn.ModuleList(self.conv_blocks_context)
self.td = nn.ModuleList(self.td)
self.tu = nn.ModuleList(self.tu)
self.seg_outputs = nn.ModuleList(self.seg_outputs)
if self.upscale_logits:
self.upscale_logits_ops = nn.ModuleList(
self.upscale_logits_ops) # lambda x:x is not a Module so we need to distinguish here
if self.weightInitializer is not None:
self.apply(self.weightInitializer)
# self.apply(print_module_training_status)
def forward(self, x):
skips = []
seg_outputs = []
for d in range(len(self.conv_blocks_context) - 1):
x = self.conv_blocks_context[d](x)
skips.append(x)
if not self.convolutional_pooling:
x = self.td[d](x)
x = self.conv_blocks_context[-1](x)
for u in range(len(self.tu)):
x = self.tu[u](x)
x = torch.cat((x, skips[-(u + 1)]), dim=1)
x = self.conv_blocks_localization[u](x)
seg_outputs.append(self.final_nonlin(self.seg_outputs[u](x)))
if self._deep_supervision and self.do_ds:
return tuple([seg_outputs[-1]] + [i(j) for i, j in
zip(list(self.upscale_logits_ops)[::-1], seg_outputs[:-1][::-1])])
else:
return seg_outputs[-1]
@staticmethod
def compute_approx_vram_consumption(patch_size, num_pool_per_axis, base_num_features, max_num_features,
num_modalities, num_classes, pool_op_kernel_sizes, deep_supervision=False,
conv_per_stage=2):
"""
This only applies for num_conv_per_stage and convolutional_upsampling=True
not real vram consumption. just a constant term to which the vram consumption will be approx proportional
(+ offset for parameter storage)
:param deep_supervision:
:param patch_size:
:param num_pool_per_axis:
:param base_num_features:
:param max_num_features:
:param num_modalities:
:param num_classes:
:param pool_op_kernel_sizes:
:return:
"""
if not isinstance(num_pool_per_axis, np.ndarray):
num_pool_per_axis = np.array(num_pool_per_axis)
npool = len(pool_op_kernel_sizes)
map_size = np.array(patch_size)
tmp = np.int64((conv_per_stage * 2 + 1) * np.prod(map_size, dtype=np.int64) * base_num_features +
num_modalities * np.prod(map_size, dtype=np.int64) +
num_classes * np.prod(map_size, dtype=np.int64))
num_feat = base_num_features
for p in range(npool):
for pi in range(len(num_pool_per_axis)):
map_size[pi] /= pool_op_kernel_sizes[p][pi]
num_feat = min(num_feat * 2, max_num_features)
num_blocks = (conv_per_stage * 2 + 1) if p < (npool - 1) else conv_per_stage # conv_per_stage + conv_per_stage for the convs of encode/decode and 1 for transposed conv
tmp += num_blocks * np.prod(map_size, dtype=np.int64) * num_feat
if deep_supervision and p < (npool - 2):
tmp += np.prod(map_size, dtype=np.int64) * num_classes
# print(p, map_size, num_feat, tmp)
return tmp
