def enas_repeat_fn(inputs, outputs, layer_id, out_filters, weight_sharer):
h_enas_op = D(
['conv3', 'conv5', 'dsep_conv3', 'dsep_conv5', 'avg_pool', 'max_pool'],
name='op_' + str(layer_id))
#h_enas_op = D(['max_pool'], name='op_' + str(layer_id))
op_inputs, op_outputs = enas_op(h_enas_op, out_filters,
'op_' + str(layer_id), weight_sharer)
outputs[list(outputs.keys())[-1]].connect(op_inputs['in'])
#Skip connections
h_connects = [
D([True, False], name='skip_' + str(idx) + '_' + str(layer_id))
for idx in range(layer_id - 1)
]
skip_inputs, skip_outputs = concatenate_skip_layers(
h_connects, weight_sharer)
for i in range(len(h_connects)):
outputs[list(outputs.keys())[i]].connect(skip_inputs['in' + str(i)])
op_outputs['out'].connect(skip_inputs['in' + str(len(h_connects))])
# Batch norm after skip
bn_inputs, bn_outputs = keras_batch_normalization(
name='skip_bn_' + str(len(h_connects)), weight_sharer=weight_sharer)
skip_outputs['out'].connect(bn_inputs['in'])
outputs['out' + str(len(outputs))] = bn_outputs['out']
return inputs, outputs
def intermediate_node_fn(num_inputs, filters):
return mo.siso_sequential([
add(num_inputs),
conv2d(D([filters]), D([3])),
batch_normalization(),
relu()
])
def generate(filters):
return cell(
lambda channels: mo.siso_sequential(
[conv2d(D([channels]), D([1])),
batch_normalization(),
relu()]),
lambda num_inputs, node_id, channels: intermediate_node_fn(
num_inputs, node_id, channels, cell_ops), concat,
h_connections, 5, filters)
def conv_op(filters, filter_size, stride, dilation_rate, spatial_separable):
if spatial_separable:
return mo.siso_sequential([
conv2d(D([filters]), D([[1, filter_size]]), D([[1, stride]])),
batch_normalization(),
relu(),
conv2d(D([filters]), D([[filter_size, 1]]), D([[stride, 1]])),
])
else:
return conv2d(D([filters]), D([filter_size]), D([stride]),
D([dilation_rate]))
def intermediate_node_fn(num_inputs, node_id, filters, cell_ops):
return mo.siso_sequential([
add(num_inputs),
mo.siso_or(
{
'conv1': lambda: conv2d(D([filters]), D([1])),
'conv3': lambda: conv2d(D([filters]), D([3])),
'max3': lambda: max_pool2d(D([3]))
}, cell_ops[node_id]),
batch_normalization(),
relu()
])
def generate_search_space(stacks, num_cells_per_stack, num_nodes_per_cell,
num_init_filters):
search_space = [stem()]
cell_fn = create_cell_generator(num_nodes_per_cell)
num_filters = num_init_filters
for i in range(stacks):
if i > 0:
search_space.append(max_pool2d(D([2]), D([2])))
num_filters *= 2
for j in range(num_cells_per_stack):
search_space.append(cell_fn(num_filters))
search_space += [global_pool2d(), fc_layer(D([10]))]
return mo.siso_sequential(search_space)
def cell_input_fn(filters):
prev_input = mo.identity()
cur_input = wrap_relu_batch_norm(conv2d(D([filters]), D([1])))
transformed_prev_input = maybe_factorized_reduction(add_relu=True)
transformed_prev_input[0]['In0'].connect(prev_input[1]['Out'])
transformed_prev_input[0]['In1'].connect(cur_input[1]['Out'])
return {
'In0': prev_input[0]['In'],
'In1': cur_input[0]['In']
}, {
'Out0': transformed_prev_input[1]['Out'],
'Out1': cur_input[1]['Out']
}
def generate_search_space(num_nodes_per_cell, num_normal_cells,
num_reduction_cells, init_filters, stem_multiplier):
global global_vars, hp_sharer
global_vars = {}
hp_sharer = hp.HyperparameterSharer()
hp_sharer.register('drop_path_keep_prob',
lambda: D([.7], name='drop_path_keep_prob'))
stem_in, stem_out = stem(int(init_filters * stem_multiplier))
progress_in, progress_out = mo.identity()
global_vars['progress'] = progress_out['Out']
normal_cell_fn = create_cell_generator(num_nodes_per_cell, False)
reduction_cell_fn = create_cell_generator(num_nodes_per_cell, True)
total_cells = num_normal_cells + num_reduction_cells
hasReduction = [False] * num_normal_cells
for i in range(num_reduction_cells):
hasReduction[int(
float(i + 1) / (num_reduction_cells + 1) *
num_normal_cells)] = True
inputs = [stem_out, stem_out]
filters = init_filters
aux_loss_idx = int(
float(num_reduction_cells) /
(num_reduction_cells + 1) * num_normal_cells) - 1
outs = {}
cells_created = 0.0
for i in range(num_normal_cells):
if hasReduction[i]:
filters *= 2
connect_new_cell(
reduction_cell_fn(filters, (cells_created + 1) / total_cells),
inputs)
cells_created += 1.0
connect_new_cell(
normal_cell_fn(filters, (cells_created + 1) / total_cells), inputs)
cells_created += 1.0
if i == aux_loss_idx:
aux_in, aux_out = aux_logits()
aux_in['In'].connect(inputs[-1]['Out'])
outs['Out0'] = aux_out['Out']
_, final_out = mo.siso_sequential([(None, inputs[-1]),
relu(),
global_pool2d(),
dropout(D([1.0])),
fc_layer(D([10]))])
outs['Out1'] = final_out['Out']
return {'In0': stem_in['In'], 'In1': progress_in['In']}, outs
def generate_stage(stage_num, num_nodes, filters, filter_size):
h_connections = [
Bool(name='%d_in_%d_%d' % (stage_num, in_id, out_id))
for (in_id,
out_id) in itertools.combinations(range(1, num_nodes + 1), 2)
]
return genetic_stage(
lambda: mo.siso_sequential([
conv2d(D([filters]), D([filter_size])),
batch_normalization(),
relu()
]), lambda num_inputs: intermediate_node_fn(num_inputs, filters), lambda
num_inputs: intermediate_node_fn(num_inputs, filters), h_connections,
num_nodes)
def enas_op(h_op_name, out_filters, name, weight_sharer):
return mo.siso_or(
{
'conv3':
lambda: enas_conv(out_filters, 3, False, weight_sharer, name),
'conv5':
lambda: enas_conv(out_filters, 5, False, weight_sharer, name),
'dsep_conv3':
lambda: enas_conv(out_filters, 3, True, weight_sharer, name),
'dsep_conv5':
lambda: enas_conv(out_filters, 5, True, weight_sharer, name),
'avg_pool':
lambda: avg_pool(D([3]), D([1])),
'max_pool':
lambda: max_pool(D([3]), D([1]))
}, h_op_name)
def intermediate_node_fn(reduction, input_id, node_id, op_num, filters,
cell_ratio, cell_ops):
stride = 2 if reduction and input_id < 2 else 1
h_is_not_none = co.DependentHyperparameter(
lambda op: op != 'none', {'op': cell_ops[node_id * 2 + op_num]})
op_in, op_out = mo.siso_or(
{
'none':
lambda: check_filters(filters, stride),
'conv1':
lambda: wrap_relu_batch_norm(
conv2d(D([filters]), D([1]), h_stride=D([stride]))),
'conv3':
lambda: full_conv_op(filters, 3, stride, 1, False),
'depth_sep3':
lambda: separable_conv_op(filters, 3, stride),
'depth_sep5':
lambda: separable_conv_op(filters, 5, stride),
'depth_sep7':
lambda: separable_conv_op(filters, 7, stride),
'dilated_3x3_rate_2':
lambda: full_conv_op(filters, 3, stride, 2, False),
'dilated_3x3_rate_4':
lambda: full_conv_op(filters, 3, stride, 4, False),
'dilated_3x3_rate_6':
lambda: full_conv_op(filters, 3, stride, 6, False),
'1x3_3x1':
lambda: full_conv_op(filters, 3, stride, 1, True),
'1x7_7x1':
lambda: full_conv_op(filters, 7, stride, 1, True),
'avg2':
lambda: pool_op(filters, 2, stride, 'avg'),
'avg3':
lambda: pool_op(filters, 3, stride, 'avg'),
'max2':
lambda: pool_op(filters, 2, stride, 'max'),
'max3':
lambda: pool_op(filters, 3, stride, 'max'),
'min2':
lambda: pool_op(filters, 2, stride, 'min')
}, cell_ops[node_id * 2 + op_num])
drop_in, drop_out = miso_optional(lambda: drop_path(cell_ratio),
h_is_not_none)
drop_in['In0'].connect(op_out['Out'])
drop_in['In1'].connect(global_vars['progress'])
return op_in, drop_out
def full_conv_op(filters, filter_size, stride, dilation_rate,
spatial_separable):
# Add bottleneck layer according to
# https://github.com/tensorflow/tpu/blob/master/models/official/amoeba_net/network_utils.py
if filter_size == 3 and spatial_separable:
reduced_filter_size = int(3 * filters / 8)
else:
reduced_filter_size = int(filters / 4)
if reduced_filter_size < 1:
return wrap_relu_batch_norm(
conv_op(filters, filter_size, stride, dilation_rate,
spatial_separable))
else:
return mo.siso_sequential([
wrap_relu_batch_norm(conv2d(D([reduced_filter_size]), D([1]))),
wrap_relu_batch_norm(
conv_op(reduced_filter_size, filter_size, stride,
dilation_rate, spatial_separable)),
wrap_relu_batch_norm(conv2d(D([filters]), D([1])))
])
def separable_conv_op(filters, filter_size, stride):
return mo.siso_sequential([
wrap_relu_batch_norm(
separable_conv2d(D([filters]), D([filter_size]), D([stride]))),
wrap_relu_batch_norm(
separable_conv2d(D([filters]), D([filter_size]), D([1])))
])
def SP1_ops(name=None, reduction=False):
if reduction:
# Dilated convolution can't be done with strides
ops = [
'none', 'depth_sep3', 'depth_sep5', 'depth_sep7', 'avg3', 'max3',
'1x7_7x1'
]
else:
ops = [
'none', 'depth_sep3', 'depth_sep5', 'depth_sep7', 'avg3', 'max3',
'dilated_3x3_rate_2', '1x7_7x1'
]
return D(ops, name=name)
def pool_op(filters, filter_size, stride, pool_type):
if pool_type == 'avg':
pool = avg_pool2d(D([filter_size]), D([stride]))
elif pool_type == 'max':
pool = max_pool2d(D([filter_size]), D([stride]))
else:
pool = min_pool2d(D([filter_size]), D([stride]))
return mo.siso_sequential([pool, check_filters(filters)])
def aux_logits():
return mo.siso_sequential([
relu(),
avg_pool2d(D([5]), D([3]), D(['VALID'])),
conv2d(D([128]), D([1])),
batch_normalization(),
relu(),
global_convolution(D([768])),
batch_normalization(),
relu(),
flatten(),
fc_layer(D([10]))
])
def __init__(self,
name,
name_to_hyperp,
compile_fn,
input_names,
output_names,
scope=None):
co.Module.__init__(self, scope, name)
for h in name_to_hyperp:
if not isinstance(name_to_hyperp[h], co.Hyperparameter):
vs = name_to_hyperp[h] if isinstance(
name_to_hyperp[h], list) else [name_to_hyperp[h]]
name_to_hyperp[h] = D(vs)
self._register(input_names, output_names, name_to_hyperp)
self._compile_fn = compile_fn
self.isTraining = True
def __init__(self,
name,
compile_fn,
name_to_hyperp,
input_names,
output_names,
scope=None):
co.Module.__init__(self, scope, name)
hyperparam_dict = {}
for h in name_to_hyperp:
if not isinstance(name_to_hyperp[h], co.Hyperparameter):
hyperparam_dict[h] = D([name_to_hyperp[h]])
else:
hyperparam_dict[h] = name_to_hyperp[h]
self._register(input_names, output_names, hyperparam_dict)
self._compile_fn = compile_fn
def get_enas_search_space(num_classes, num_layers, out_filters, weight_sharer):
h_N = D([num_layers], name='num_layers')
return mo.siso_sequential([
enas_space(
h_N,
out_filters,
#mo.empty,
lambda: wrap_batch_norm_relu(conv2D(
3, 'stem', weight_sharer, out_filters=out_filters),
add_relu=False,
weight_sharer=weight_sharer,
name='stem'),
enas_repeat_fn,
['in'],
['out'],
weight_sharer),
global_pool(),
dropout(keep_prob=.9),
fc_layer(num_classes, 'softmax', weight_sharer),
])
def create_cell_generator(num_nodes, reduction):
prefix = 'reduction' if reduction else 'normal'
cell_ops = [
SP1_ops('%s_op_%d_%d' % (prefix, i // 2, i % 2), reduction)
for i in range(2 * num_nodes)
]
connection_hparams = [
D(list(range(i // 2 + 2)),
name='%s_in_%d_%d' % (prefix, i // 2, i % 2))
for i in range(2 * num_nodes)
]
def generate(filters, cell_ratio):
return cell(
lambda: cell_input_fn(filters),
lambda in_id, node_id, op_num: intermediate_node_fn(
reduction, in_id, node_id, op_num, filters, cell_ratio,
cell_ops), lambda: add(2), combine_unused, num_nodes,
connection_hparams)
return generate
def generate_search_space(nodes_per_stage, filters_per_stage,
filter_size_per_stage):
search_space = []
for i in range(len(nodes_per_stage)):
search_space.append(
generate_stage(i, nodes_per_stage[i], filters_per_stage[i],
filter_size_per_stage[i]))
search_space.append(max_pool2d(D([3]), D([2]), D(['SAME'])))
search_space += [
flatten(),
fc_layer(D([1024])),
dropout(D([.5])),
fc_layer(D([10]))
]
return mo.siso_sequential(search_space)
def create_cell_generator(num_nodes):
h_connections = [
Bool(name='in_%d_%d' % (in_id, out_id))
for (in_id, out_id) in itertools.combinations(range(num_nodes + 2), 2)
]
cell_ops = [
D(['conv1', 'conv3', 'max3'], name='node_%d' % i)
for i in range(num_nodes)
]
def generate(filters):
return cell(
lambda channels: mo.siso_sequential(
[conv2d(D([channels]), D([1])),
batch_normalization(),
relu()]),
lambda num_inputs, node_id, channels: intermediate_node_fn(
num_inputs, node_id, channels, cell_ops), concat,
h_connections, 5, filters)
return generate
def stem():
return mo.siso_sequential([
conv2d(D([128]), D([3])),
batch_normalization(),
relu(),
])
def stem(filters):
return mo.siso_sequential(
[conv2d(D([filters]), D([3])),
batch_normalization()])
def relu():
return activation(D(['relu']))