openvino/model-optimizer/extensions/front/softmax.py

74 lines
2.8 KiB
Python

# Copyright (C) 2018-2021 Intel Corporation
# SPDX-License-Identifier: Apache-2.0
import logging as log
import numpy as np
from extensions.front.reduce_axis_normalizer import ReduceAxisNormalizer
from mo.front.common.replacement import FrontReplacementSubgraph
from mo.front.subgraph_matcher import SubgraphMatch
from mo.graph.graph import Graph
from mo.ops.softmax import Softmax
class SoftmaxFromKeras(FrontReplacementSubgraph):
"""
The transformation looks for the pattern that Keras produces for SoftMax layer. The transformation works if the
softmax is performed over one pre-defined axis.
"""
enabled = True
def run_after(self):
return [ReduceAxisNormalizer]
def pattern(self):
return dict(
nodes=[
('input', dict()),
('reduce_max', dict(op='ReduceMax')),
('reduce_indices_max', dict(op='Const', value=lambda x: x is not None and x.size != 0)),
('sub', dict(op='Sub')),
('exp', dict(op='Exp')),
('reduce_sum', dict(op='ReduceSum')),
('reduce_indices_sum', dict(op='Const', value=lambda x: x is not None and x.size != 0)),
('div', dict(op='Div')),
],
edges=[
('input', 'sub', {'in': 0}),
('input', 'reduce_max', {'in': 0}),
('reduce_indices_max', 'reduce_max', {'in': 1}),
('reduce_max', 'sub', {'in': 1}),
('sub', 'exp', {'in': 0}),
('exp', 'div', {'in': 0}),
('exp', 'reduce_sum', {'in': 0}),
('reduce_indices_sum', 'reduce_sum', {'in': 1}),
('reduce_sum', 'div', {'in': 1}),
])
def replace_sub_graph(self, graph: Graph, match: [dict, SubgraphMatch]):
reduce_max_axis = match['reduce_indices_max'].value
reduce_sum_axis = match['reduce_indices_sum'].value
if reduce_max_axis.ndim == 0:
reduce_max_axis = reduce_max_axis.reshape([1])
if reduce_sum_axis.ndim == 0:
reduce_sum_axis = reduce_sum_axis.reshape([1])
if len(reduce_max_axis) != 1:
log.info('The reductions indices contain more than 1 element. Cannot convert to Softmax.')
return
if not np.array_equal(reduce_max_axis, reduce_sum_axis):
log.info('The reduce indices are not equal: {} vs {}. Cannot convert to Softmax'
''.format(reduce_max_axis, reduce_sum_axis))
return
softmax = Softmax(graph, {'name': match['input'].name + '/Softmax', 'axis': reduce_sum_axis[0]}).create_node()
match['input'].out_port(0).connect(softmax.in_port(0))
match['div'].out_port(0).get_connection().set_source(softmax.out_port(0))
log.debug('Successfully created SoftMax node')