[Bugfix] Corrects activation for DenseNetFCNs (#55)

* Bugfix for DenseNetFCN + Activation parameter + revert to Keras 1 model

* Correct ordering of parameters (input_shape) for DenseNet models

* Updated to Keras 2 API

* Changed image_dim_ordering to image_data_format

* Corrected "th" to channels_first and "tf" to channels_last

* Fixed " to '

* PEP 8 fixes

* Fix PEP 8 again
This commit is contained in:
Somshubra Majumdar
2017-04-15 10:18:10 -07:00
committed by Michael Oliver
parent 8ef69698b8
commit 1d57dd3c63
+105 -123
View File
@@ -1,11 +1,9 @@
# -*- coding: utf-8 -*-
"""DenseNet models for Keras.
'''DenseNet models for Keras.
# Reference
- [Densely Connected Convolutional Networks](https://arxiv.org/pdf/1608.06993.pdf)
- [The One Hundred Layers Tiramisu: Fully Convolutional DenseNets for Semantic Segmentation](https://arxiv.org/pdf/1611.09326.pdf)
"""
'''
from __future__ import print_function
from __future__ import absolute_import
from __future__ import division
@@ -14,11 +12,11 @@ import warnings
from keras.models import Model
from keras.layers.core import Dense, Dropout, Activation, Reshape
from keras.layers import Deconvolution2D, AtrousConvolution2D, UpSampling2D
from keras.layers.merge import concatenate
from keras.layers.convolutional import Conv2D, Conv2DTranspose, UpSampling2D
from keras.layers.pooling import AveragePooling2D
from keras.layers.pooling import GlobalAveragePooling2D
from keras.layers import Input, Conv2D
from keras.layers import Input
from keras.layers.merge import concatenate
from keras.layers.normalization import BatchNormalization
from keras.regularizers import l2
from keras.utils.layer_utils import convert_all_kernels_in_model
@@ -35,23 +33,28 @@ TH_WEIGHTS_PATH_NO_TOP = 'https://github.com/titu1994/DenseNet/releases/download
TF_WEIGHTS_PATH_NO_TOP = 'https://github.com/titu1994/DenseNet/releases/download/v2.0/DenseNet-40-12-Tensorflow-Backend-TF-dim-ordering-no-top.h5'
def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers_per_block=-1,
def DenseNet(input_shape=None, depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers_per_block=-1,
bottleneck=False, reduction=0.0, dropout_rate=0.0, weight_decay=1E-4,
include_top=True, weights='cifar10', input_tensor=None, input_shape=None,
classes=10):
"""Instantiate the DenseNet architecture,
include_top=True, weights='cifar10', input_tensor=None,
classes=10, activation='softmax'):
'''Instantiate the DenseNet architecture,
optionally loading weights pre-trained
on CIFAR-10. Note that when using TensorFlow,
for best performance you should set
`image_dim_ordering="tf"` in your Keras config
`image_data_format='channels_last'` in your Keras config
at ~/.keras/keras.json.
The model and the weights are compatible with both
TensorFlow and Theano. The dimension ordering
convention used by the model is the one
specified in your Keras config file.
# Arguments
input_shape: optional shape tuple, only to be specified
if `include_top` is False (otherwise the input shape
has to be `(32, 32, 3)` (with `channels_last` dim ordering)
or `(3, 32, 32)` (with `channels_first` dim ordering).
It should have exactly 3 inputs channels,
and width and height should be no smaller than 8.
E.g. `(200, 200, 3)` would be one valid value.
depth: number or layers in the DenseNet
nb_dense_block: number of dense blocks to add to end (generally = 3)
growth_rate: number of filters to add per dense block
@@ -59,7 +62,7 @@ def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers
number of filters is 2 * growth_rate
nb_layers_per_block: number of layers in each dense block.
Can be a -1, positive integer or a list.
If -1, calculates nb_layer_per_block from the depth of the network.
If -1, calculates nb_layer_per_block from the network depth.
If positive integer, a set number of layers per dense block.
If list, nb_layer is used as provided. Note that list size must
be (nb_dense_block + 1)
@@ -71,23 +74,17 @@ def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers
include_top: whether to include the fully-connected
layer at the top of the network.
weights: one of `None` (random initialization) or
"cifar10" (pre-training on CIFAR-10)..
'cifar10' (pre-training on CIFAR-10)..
input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
to use as image input for the model.
input_shape: optional shape tuple, only to be specified
if `include_top` is False (otherwise the input shape
has to be `(32, 32, 3)` (with `tf` dim ordering)
or `(3, 32, 32)` (with `th` dim ordering).
It should have exactly 3 inputs channels,
and width and height should be no smaller than 8.
E.g. `(200, 200, 3)` would be one valid value.
classes: optional number of classes to classify images
into, only to be specified if `include_top` is True, and
if no `weights` argument is specified.
activation: Type of activation at the top layer. Can be one of 'softmax' or 'sigmoid'.
Note that if sigmoid is used, classes must be 1.
# Returns
A Keras model instance.
"""
'''
if weights not in {'cifar10', None}:
raise ValueError('The `weights` argument should be either '
@@ -98,11 +95,17 @@ def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers
raise ValueError('If using `weights` as CIFAR 10 with `include_top`'
' as true, `classes` should be 10')
if activation not in ['softmax', 'sigmoid']:
raise ValueError('activation must be one of "softmax" or "sigmoid"')
if activation == 'sigmoid' and classes != 1:
raise ValueError('sigmoid activation can only be used when classes = 1')
# Determine proper input shape
input_shape = _obtain_input_shape(input_shape,
default_size=32,
min_size=8,
data_format=K.image_dim_ordering(),
data_format=K.image_data_format(),
include_top=include_top)
if input_tensor is None:
@@ -115,7 +118,7 @@ def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers
x = __create_dense_net(classes, img_input, include_top, depth, nb_dense_block,
growth_rate, nb_filter, nb_layers_per_block, bottleneck, reduction,
dropout_rate, weight_decay)
dropout_rate, weight_decay, activation)
# Ensure that the model takes into account
# any potential predecessors of `input_tensor`.
@@ -132,7 +135,7 @@ def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers
(bottleneck is False) and (reduction == 0.0) and (dropout_rate == 0.0) and (weight_decay == 1E-4):
# Default parameters match. Weights for this model exist:
if K.image_dim_ordering() == 'th':
if K.image_data_format() == 'channels_first':
if include_top:
weights_path = get_file('densenet_40_12_th_dim_ordering_th_kernels.h5',
TH_WEIGHTS_PATH,
@@ -148,9 +151,9 @@ def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers
warnings.warn('You are using the TensorFlow backend, yet you '
'are using the Theano '
'image dimension ordering convention '
'(`image_dim_ordering="th"`). '
'(`image_data_format="channels_first"`). '
'For best performance, set '
'`image_dim_ordering="tf"` in '
'`image_data_format="channels_last"` in '
'your Keras config '
'at ~/.keras/keras.json.')
convert_all_kernels_in_model(model)
@@ -174,14 +177,13 @@ def DenseNet(depth=40, nb_dense_block=3, growth_rate=12, nb_filter=16, nb_layers
def DenseNetFCN(input_shape, nb_dense_block=5, growth_rate=16, nb_layers_per_block=4,
reduction=0.0, dropout_rate=0.0, weight_decay=1E-4, init_conv_filters=48,
include_top=True, weights=None, input_tensor=None, classes=1,
upsampling_conv=128, upsampling_type='upsampling', batchsize=None):
"""Instantiate the DenseNet FCN architecture.
include_top=True, weights=None, input_tensor=None, classes=1, activation='softmax',
upsampling_conv=128, upsampling_type='upsampling'):
'''Instantiate the DenseNet FCN architecture.
Note that when using TensorFlow,
for best performance you should set
`image_dim_ordering="tf"` in your Keras config
`image_data_format='channels_last'` in your Keras config
at ~/.keras/keras.json.
# Arguments
nb_dense_block: number of dense blocks to add to end (generally = 3)
growth_rate: number of filters to add per dense block
@@ -198,30 +200,31 @@ def DenseNetFCN(input_shape, nb_dense_block=5, growth_rate=16, nb_layers_per_blo
include_top: whether to include the fully-connected
layer at the top of the network.
weights: one of `None` (random initialization) or
"cifar10" (pre-training on CIFAR-10)..
'cifar10' (pre-training on CIFAR-10)..
input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
to use as image input for the model.
input_shape: optional shape tuple, only to be specified
if `include_top` is False (otherwise the input shape
has to be `(32, 32, 3)` (with `tf` dim ordering)
or `(3, 32, 32)` (with `th` dim ordering).
has to be `(32, 32, 3)` (with `channels_last` dim ordering)
or `(3, 32, 32)` (with `channels_first` dim ordering).
It should have exactly 3 inputs channels,
and width and height should be no smaller than 8.
E.g. `(200, 200, 3)` would be one valid value.
classes: optional number of classes to classify images
into, only to be specified if `include_top` is True, and
if no `weights` argument is specified.
activation: Type of activation at the top layer. Can be one of 'softmax' or 'sigmoid'.
Note that if sigmoid is used, classes must be 1.
upsampling_conv: number of convolutional layers in upsampling via subpixel convolution
upsampling_type: Can be one of 'upsampling', 'deconv', 'atrous' and
upsampling_type: Can be one of 'upsampling', 'deconv' and
'subpixel'. Defines type of upsampling algorithm used.
batchsize: Fixed batch size. This is a temporary requirement for
computation of output shape in the case of Deconvolution2D layers.
Parameter will be removed in next iteration of Keras, which infers
output shape of deconvolution layers automatically.
# Returns
A Keras model instance.
"""
'''
if weights not in {None}:
raise ValueError('The `weights` argument should be '
@@ -230,13 +233,9 @@ def DenseNetFCN(input_shape, nb_dense_block=5, growth_rate=16, nb_layers_per_blo
upsampling_type = upsampling_type.lower()
if upsampling_type not in ['upsampling', 'deconv', 'atrous', 'subpixel']:
if upsampling_type not in ['upsampling', 'deconv', 'subpixel']:
raise ValueError('Parameter "upsampling_type" must be one of "upsampling", '
'"deconv", "atrous" or "subpixel".')
if upsampling_type == 'deconv' and batchsize is None:
raise ValueError('If "upsampling_type" is deconvoloution, then a fixed '
'batch size must be provided in batchsize parameter.')
'"deconv" or "subpixel".')
if input_shape is None:
raise ValueError('For fully convolutional models, input shape must be supplied.')
@@ -245,17 +244,33 @@ def DenseNetFCN(input_shape, nb_dense_block=5, growth_rate=16, nb_layers_per_blo
raise ValueError('Number of dense layers per block must be greater than 1. Argument '
'value was %d.' % (nb_layers_per_block))
if upsampling_type == 'atrous':
warnings.warn('Atrous Convolution upsampling does not correctly work (see https://github.com/fchollet/keras/issues/4018).\n'
'Switching to `upsampling` type upscaling.')
upsampling_type = 'upsampling'
if activation not in ['softmax', 'sigmoid']:
raise ValueError('activation must be one of "softmax" or "sigmoid"')
if activation == 'sigmoid' and classes != 1:
raise ValueError('sigmoid activation can only be used when classes = 1')
# Determine proper input shape
input_shape = _obtain_input_shape(input_shape,
default_size=32,
min_size=16,
data_format=K.image_dim_ordering(),
include_top=include_top)
min_size = 2 ** nb_dense_block
if K.image_data_format() == 'channels_first':
if input_shape is not None:
if ((input_shape[1] is not None and input_shape[1] < min_size) or
(input_shape[2] is not None and input_shape[2] < min_size)):
raise ValueError('Input size must be at least ' +
str(min_size) + 'x' + str(min_size) + ', got '
'`input_shape=' + str(input_shape) + '`')
else:
input_shape = (classes, None, None)
else:
if input_shape is not None:
if ((input_shape[0] is not None and input_shape[0] < min_size) or
(input_shape[1] is not None and input_shape[1] < min_size)):
raise ValueError('Input size must be at least ' +
str(min_size) + 'x' + str(min_size) + ', got '
'`input_shape=' + str(input_shape) + '`')
else:
input_shape = (None, None, classes)
if input_tensor is None:
img_input = Input(shape=input_shape)
@@ -268,7 +283,7 @@ def DenseNetFCN(input_shape, nb_dense_block=5, growth_rate=16, nb_layers_per_blo
x = __create_fcn_dense_net(classes, img_input, include_top, nb_dense_block,
growth_rate, reduction, dropout_rate, weight_decay,
nb_layers_per_block, upsampling_conv, upsampling_type,
batchsize, init_conv_filters, input_shape)
init_conv_filters, input_shape, activation)
# Ensure that the model takes into account
# any potential predecessors of `input_tensor`.
@@ -284,18 +299,16 @@ def DenseNetFCN(input_shape, nb_dense_block=5, growth_rate=16, nb_layers_per_blo
def __conv_block(ip, nb_filter, bottleneck=False, dropout_rate=None, weight_decay=1E-4):
''' Apply BatchNorm, Relu, 3x3 Conv2D, optional bottleneck block and dropout
Args:
ip: Input keras tensor
nb_filter: number of filters
bottleneck: add bottleneck block
dropout_rate: dropout rate
weight_decay: weight decay factor
Returns: keras tensor with batch_norm, relu and convolution2d added (optional bottleneck)
'''
concat_axis = 1 if K.image_dim_ordering() == 'th' else -1
concat_axis = 1 if K.image_data_format() == 'channels_first' else -1
x = BatchNormalization(axis=concat_axis, gamma_regularizer=l2(weight_decay),
beta_regularizer=l2(weight_decay))(ip)
@@ -310,12 +323,12 @@ def __conv_block(ip, nb_filter, bottleneck=False, dropout_rate=None, weight_deca
if dropout_rate:
x = Dropout(dropout_rate)(x)
x = BatchNormalization(mode=0, axis=concat_axis, gamma_regularizer=l2(weight_decay),
x = BatchNormalization(axis=concat_axis, gamma_regularizer=l2(weight_decay),
beta_regularizer=l2(weight_decay))(x)
x = Activation('relu')(x)
x = Conv2D(nb_filter, (3, 3), kernel_initializer='he_uniform', padding='same', use_bias=False,
kernel_regularizer=l2(weight_decay))(x)
kenel_regularizer=l2(weight_decay))(x)
if dropout_rate:
x = Dropout(dropout_rate)(x)
@@ -324,7 +337,6 @@ def __conv_block(ip, nb_filter, bottleneck=False, dropout_rate=None, weight_deca
def __transition_block(ip, nb_filter, compression=1.0, dropout_rate=None, weight_decay=1E-4):
''' Apply BatchNorm, Relu 1x1, Conv2D, optional compression, dropout and Maxpooling2D
Args:
ip: keras tensor
nb_filter: number of filters
@@ -332,16 +344,15 @@ def __transition_block(ip, nb_filter, compression=1.0, dropout_rate=None, weight
in the transition block.
dropout_rate: dropout rate
weight_decay: weight decay factor
Returns: keras tensor, after applying batch_norm, relu-conv, dropout, maxpool
'''
concat_axis = 1 if K.image_dim_ordering() == 'th' else -1
concat_axis = 1 if K.image_data_format() == 'channels_first' else -1
x = BatchNormalization(axis=concat_axis, gamma_regularizer=l2(weight_decay),
beta_regularizer=l2(weight_decay))(ip)
x = Activation('relu')(x)
x = Conv2D(nb_filter, (3, 3), kernel_initializer='he_uniform', padding='same', use_bias=False,
x = Conv2D(int(nb_filter * compression), (1, 1), kernel_initializer='he_uniform', padding='same', use_bias=False,
kernel_regularizer=l2(weight_decay))(x)
if dropout_rate:
x = Dropout(dropout_rate)(x)
@@ -353,7 +364,6 @@ def __transition_block(ip, nb_filter, compression=1.0, dropout_rate=None, weight
def __dense_block(x, nb_layers, nb_filter, growth_rate, bottleneck=False, dropout_rate=None, weight_decay=1E-4,
grow_nb_filters=True, return_concat_list=False):
''' Build a dense_block where the output of each conv_block is fed to subsequent ones
Args:
x: keras tensor
nb_layers: the number of layers of conv_block to append to the model.
@@ -364,11 +374,10 @@ def __dense_block(x, nb_layers, nb_filter, growth_rate, bottleneck=False, dropou
weight_decay: weight decay factor
grow_nb_filters: flag to decide to allow number of filters to grow
return_concat_list: return the list of feature maps along with the actual output
Returns: keras tensor with nb_layers of conv_block appended
'''
concat_axis = 1 if K.image_dim_ordering() == 'th' else -1
concat_axis = 1 if K.image_data_format() == 'channels_first' else -1
x_list = [x]
@@ -376,53 +385,46 @@ def __dense_block(x, nb_layers, nb_filter, growth_rate, bottleneck=False, dropou
x = __conv_block(x, growth_rate, bottleneck, dropout_rate, weight_decay)
x_list.append(x)
x1 = concatenate(x_list, axis=concat_axis)
x = concatenate(x_list, axis=concat_axis)
if grow_nb_filters:
nb_filter += growth_rate
if return_concat_list:
return x1, nb_filter, x_list
return x, nb_filter, x_list
else:
return x1, nb_filter
return x, nb_filter
def __transition_up_block(ip, nb_filters, type='upsampling', output_shape=None, weight_decay=1E-4):
def __transition_up_block(ip, nb_filters, type='upsampling', weight_decay=1E-4):
''' SubpixelConvolutional Upscaling (factor = 2)
Args:
ip: keras tensor
nb_filters: number of layers
type: can be 'upsampling', 'subpixel', 'deconv', or 'atrous'. Determines type of upsampling performed
output_shape: required if type = 'deconv'. Output shape of tensor
type: can be 'upsampling', 'subpixel', 'deconv'. Determines type of upsampling performed
weight_decay: weight decay factor
Returns: keras tensor, after applying upsampling operation.
'''
if type == 'upsampling':
x = UpSampling2D()(ip)
elif type == 'subpixel':
x = Conv2D(nb_filters, (3, 3), padding='same', kernel_regularizer=l2(weight_decay), activation='relu',
x = Conv2D(nb_filters, (3, 3), activation='relu', padding='same', W_regularizer=l2(weight_decay),
use_bias=False, kernel_initializer='he_uniform')(ip)
x = SubPixelUpscaling(scale_factor=2)(x)
x = Conv2D(nb_filters, (3, 3), activation='relu', padding='same', kernel_regularizer=l2(weight_decay),
x = Conv2D(nb_filters, (3, 3), activation='relu', padding='same', W_regularizer=l2(weight_decay),
use_bias=False, kernel_initializer='he_uniform')(x)
elif type == 'atrous':
# waiting on https://github.com/fchollet/keras/issues/4018
x = AtrousConvolution2D(nb_filters, 3, 3, activation='relu', W_regularizer=l2(weight_decay),
bias=False, atrous_rate=(2, 2), init='he_uniform')(ip)
else:
x = Deconvolution2D(nb_filters, 3, 3, output_shape, activation='relu', border_mode='same',
subsample=(2, 2), init='he_uniform')(ip)
x = Conv2DTranspose(nb_filters, (3, 3), activation='relu', padding='same', strides=(2, 2),
kernel_initializer='he_uniform')(ip)
return x
def __create_dense_net(nb_classes, img_input, include_top, depth=40, nb_dense_block=3, growth_rate=12, nb_filter=-1,
nb_layers_per_block=-1, bottleneck=False, reduction=0.0, dropout_rate=None, weight_decay=1E-4):
nb_layers_per_block=-1, bottleneck=False, reduction=0.0, dropout_rate=None, weight_decay=1E-4,
activation='softmax'):
''' Build the DenseNet model
Args:
nb_classes: number of classes
img_input: tuple of shape (channels, rows, columns) or (rows, columns, channels)
@@ -441,11 +443,12 @@ def __create_dense_net(nb_classes, img_input, include_top, depth=40, nb_dense_bl
reduction: reduction factor of transition blocks. Note : reduction value is inverted to compute compression
dropout_rate: dropout rate
weight_decay: weight decay
activation: Type of activation at the top layer. Can be one of 'softmax' or 'sigmoid'.
Note that if sigmoid is used, classes must be 1.
Returns: keras tensor with nb_layers of conv_block appended
'''
concat_axis = 1 if K.image_dim_ordering() == 'th' else -1
concat_axis = 1 if K.image_data_format() == 'channels_first' else -1
assert (depth - 4) % 3 == 0, 'Depth must be 3 N + 4'
if reduction != 0.0:
@@ -479,8 +482,8 @@ def __create_dense_net(nb_classes, img_input, include_top, depth=40, nb_dense_bl
compression = 1.0 - reduction
# Initial convolution
x = Conv2D(nb_filter, (3, 3), kernel_initializer='he_uniform', padding='same', name='initial_conv2D', use_bias=False,
kernel_regularizer=l2(weight_decay))(img_input)
x = Conv2D(nb_filter, (3, 3), kernel_initializer='he_uniform', padding='same', name='initial_conv2D',
use_bias=False, kernel_regularizer=l2(weight_decay))(img_input)
# Add dense blocks
for block_idx in range(nb_dense_block - 1):
@@ -501,7 +504,7 @@ def __create_dense_net(nb_classes, img_input, include_top, depth=40, nb_dense_bl
x = GlobalAveragePooling2D()(x)
if include_top:
x = Dense(nb_classes, activation='softmax', kernel_regularizer=l2(weight_decay), bias_regularizer=l2(weight_decay))(x)
x = Dense(nb_classes, activation=activation, W_regularizer=l2(weight_decay), b_regularizer=l2(weight_decay))(x)
return x
@@ -509,9 +512,8 @@ def __create_dense_net(nb_classes, img_input, include_top, depth=40, nb_dense_bl
def __create_fcn_dense_net(nb_classes, img_input, include_top, nb_dense_block=5, growth_rate=12,
reduction=0.0, dropout_rate=None, weight_decay=1E-4,
nb_layers_per_block=4, nb_upsampling_conv=128, upsampling_type='upsampling',
batchsize=None, init_conv_filters=48, input_shape=None):
init_conv_filters=48, input_shape=None, activation='softmax'):
''' Build the DenseNet model
Args:
nb_classes: number of classes
img_input: tuple of shape (channels, rows, columns) or (rows, columns, channels)
@@ -527,20 +529,17 @@ def __create_fcn_dense_net(nb_classes, img_input, include_top, nb_dense_block=5,
If list, nb_layer is used as provided. Note that list size must
be (nb_dense_block + 1)
nb_upsampling_conv: number of convolutional layers in upsampling via subpixel convolution
upsampling_type: Can be one of 'upsampling', 'deconv', 'atrous' and
'subpixel'. Defines type of upsampling algorithm used.
batchsize: Fixed batch size. This is a temporary requirement for
computation of output shape in the case of Deconvolution2D layers.
Parameter will be removed in next iteration of Keras, which infers
output shape of deconvolution layers automatically.
upsampling_type: Can be one of 'upsampling', 'deconv' and 'subpixel'. Defines
type of upsampling algorithm used.
input_shape: Only used for shape inference in fully convolutional networks.
activation: Type of activation at the top layer. Can be one of 'softmax' or 'sigmoid'.
Note that if sigmoid is used, classes must be 1.
Returns: keras tensor with nb_layers of conv_block appended
'''
concat_axis = 1 if K.image_dim_ordering() == 'th' else -1
concat_axis = 1 if K.image_data_format() == 'channels_first' else -1
if concat_axis == 1: # th dim ordering
if concat_axis == 1: # channels_first dim ordering
_, rows, cols = input_shape
else:
rows, cols, _ = input_shape
@@ -601,36 +600,19 @@ def __create_fcn_dense_net(nb_classes, img_input, include_top, nb_dense_block=5,
skip_list = skip_list[::-1] # reverse the skip list
if K.image_dim_ordering() == 'th':
out_shape = [batchsize, nb_filter, rows // 16, cols // 16]
else:
out_shape = [batchsize, rows // 16, cols // 16, nb_filter]
# Add dense blocks and transition up block
for block_idx in range(nb_dense_block):
n_filters_keep = growth_rate * nb_layers[nb_dense_block + block_idx]
if K.image_dim_ordering() == 'th':
out_shape[1] = n_filters_keep
else:
out_shape[3] = n_filters_keep
# upsampling block must upsample only the feature maps (concat_list[1:]),
# not the concatenation of the input with the feature maps (concat_list[0].
l = concatenate(concat_list[1:], axis=concat_axis)
t = __transition_up_block(l, nb_filters=n_filters_keep, type=upsampling_type, output_shape=out_shape)
t = __transition_up_block(l, nb_filters=n_filters_keep, type=upsampling_type)
# concatenate the skip connection with the transition block
x = concatenate([t, skip_list[block_idx]], axis=concat_axis)
if K.image_dim_ordering() == 'th':
out_shape[2] *= 2
out_shape[3] *= 2
else:
out_shape[1] *= 2
out_shape[2] *= 2
# Dont allow the feature map size to grow in upsampling dense blocks
_, nb_filter, concat_list = __dense_block(x, nb_layers[nb_dense_block + block_idx + 1], nb_filter=growth_rate,
growth_rate=growth_rate, dropout_rate=dropout_rate,
@@ -641,13 +623,13 @@ def __create_fcn_dense_net(nb_classes, img_input, include_top, nb_dense_block=5,
x = Conv2D(nb_classes, (1, 1), activation='linear', padding='same', kernel_regularizer=l2(weight_decay),
use_bias=False)(x)
if K.image_dim_ordering() == 'th':
if K.image_data_format() == 'channels_first':
channel, row, col = input_shape
else:
row, col, channel = input_shape
x = Reshape((row * col, nb_classes))(x)
x = Activation('softmax')(x)
x = Activation(activation)(x)
x = Reshape((row, col, nb_classes))(x)
return x