History

tools/python: add script to convert TensorFlow model (.pb) to native model (.model)

For example, given TensorFlow model file espcn.pb, to generate native model file espcn.model, just run: python convert.py espcn.pb In current implementation, the native model file is generated for specific dnn network with hard-code python scripts maintained out of ffmpeg. For example, srcnn network used by vf_sr is generated with https://github.com/HighVoltageRocknRoll/sr/blob/master/generate_header_and_model.py#L85 In this patch, the script is designed as a general solution which converts general TensorFlow model .pb file into .model file. The script now has some tricky to be compatible with current implemention, will be refined step by step. The script is also added into ffmpeg source tree. It is expected there will be many more patches and community needs the ownership of it. Another technical direction is to do the conversion in c/c++ code within ffmpeg source tree. While .pb file is organized with protocol buffers, it is not easy to do such work with tiny c/c++ code, see more discussion at http://ffmpeg.org/pipermail/ffmpeg-devel/2019-May/244496.html. So, choose the python script.

Guo, Yejun committed 7 years ago

Commit 50e194e1 parent 4877b583 files · +254 −0Browse files

Showing the changes to tools/python (2 of 3 files). Show all

Unified · Split

2 files
  1. tools/python/convert.py +52 −0
  2. tools/python/convert_from_tensorflow.py +201 −0
tools/python/convert.py+52−0
@@ -0,0 +1,52 @@
1# Copyright (c) 2019 Guo Yejun
2#
3# This file is part of FFmpeg.
4#
5# FFmpeg is free software; you can redistribute it and/or
6# modify it under the terms of the GNU Lesser General Public
7# License as published by the Free Software Foundation; either
8# version 2.1 of the License, or (at your option) any later version.
9#
10# FFmpeg is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13# Lesser General Public License for more details.
14#
15# You should have received a copy of the GNU Lesser General Public
16# License along with FFmpeg; if not, write to the Free Software
17# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18# ==============================================================================
19
20# verified with Python 3.5.2 on Ubuntu 16.04
21import argparse
22import os
23from convert_from_tensorflow import *
24
25def get_arguments():
26 parser = argparse.ArgumentParser(description='generate native mode model with weights from deep learning model')
27 parser.add_argument('--outdir', type=str, default='./', help='where to put generated files')
28 parser.add_argument('--infmt', type=str, default='tensorflow', help='format of the deep learning model')
29 parser.add_argument('infile', help='path to the deep learning model with weights')
30
31 return parser.parse_args()
32
33def main():
34 args = get_arguments()
35
36 if not os.path.isfile(args.infile):
37 print('the specified input file %s does not exist' % args.infile)
38 exit(1)
39
40 if not os.path.exists(args.outdir):
41 print('create output directory %s' % args.outdir)
42 os.mkdir(args.outdir)
43
44 basefile = os.path.split(args.infile)[1]
45 basefile = os.path.splitext(basefile)[0]
46 outfile = os.path.join(args.outdir, basefile) + '.model'
47
48 if args.infmt == 'tensorflow':
49 convert_from_tensorflow(args.infile, outfile)
50
51if __name__ == '__main__':
52 main()
tools/python/convert_from_tensorflow.py+201−0
@@ -0,0 +1,201 @@
1# Copyright (c) 2019 Guo Yejun
2#
3# This file is part of FFmpeg.
4#
5# FFmpeg is free software; you can redistribute it and/or
6# modify it under the terms of the GNU Lesser General Public
7# License as published by the Free Software Foundation; either
8# version 2.1 of the License, or (at your option) any later version.
9#
10# FFmpeg is distributed in the hope that it will be useful,
11# but WITHOUT ANY WARRANTY; without even the implied warranty of
12# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13# Lesser General Public License for more details.
14#
15# You should have received a copy of the GNU Lesser General Public
16# License along with FFmpeg; if not, write to the Free Software
17# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18# ==============================================================================
19
20import tensorflow as tf
21import numpy as np
22import sys, struct
23
24__all__ = ['convert_from_tensorflow']
25
26# as the first step to be compatible with vf_sr, it is not general.
27# it will be refined step by step.
28
29class TFConverter:
30 def __init__(self, graph_def, nodes, outfile):
31 self.graph_def = graph_def
32 self.nodes = nodes
33 self.outfile = outfile
34 self.layer_number = 0
35 self.output_names = []
36 self.name_node_dict = {}
37 self.edges = {}
38 self.conv_activations = {'Relu':0, 'Tanh':1, 'Sigmoid':2, 'LeakyRelu':4}
39 self.conv_paddings = {'VALID':2, 'SAME':1}
40 self.converted_nodes = set()
41 self.op2code = {'Conv2D':1, 'DepthToSpace':2}
42
43
44 def dump_for_tensorboard(self):
45 graph = tf.get_default_graph()
46 tf.import_graph_def(self.graph_def, name="")
47 # tensorboard --logdir=/tmp/graph
48 tf.summary.FileWriter('/tmp/graph', graph)
49
50
51 def get_conv2d_params(self, node):
52 knode = self.name_node_dict[node.input[1]]
53 bnode = None
54 activation = 'None'
55 next = self.edges[node.name][0]
56 if next.op == 'BiasAdd':
57 self.converted_nodes.add(next.name)
58 bnode = self.name_node_dict[next.input[1]]
59 next = self.edges[next.name][0]
60 if next.op in self.conv_activations:
61 self.converted_nodes.add(next.name)
62 activation = next.op
63 return knode, bnode, activation
64
65
66 def dump_conv2d_to_file(self, node, f):
67 assert(node.op == 'Conv2D')
68 self.layer_number = self.layer_number + 1
69 self.converted_nodes.add(node.name)
70 knode, bnode, activation = self.get_conv2d_params(node)
71
72 dilation = node.attr['dilations'].list.i[0]
73 padding = node.attr['padding'].s
74 padding = self.conv_paddings[padding.decode("utf-8")]
75
76 ktensor = knode.attr['value'].tensor
77 filter_height = ktensor.tensor_shape.dim[0].size
78 filter_width = ktensor.tensor_shape.dim[1].size
79 in_channels = ktensor.tensor_shape.dim[2].size
80 out_channels = ktensor.tensor_shape.dim[3].size
81 kernel = np.frombuffer(ktensor.tensor_content, dtype=np.float32)
82 kernel = kernel.reshape(filter_height, filter_width, in_channels, out_channels)
83 kernel = np.transpose(kernel, [3, 0, 1, 2])
84
85 np.array([self.op2code[node.op], dilation, padding, self.conv_activations[activation], in_channels, out_channels, filter_height], dtype=np.uint32).tofile(f)
86 kernel.tofile(f)
87
88 btensor = bnode.attr['value'].tensor
89 if btensor.tensor_shape.dim[0].size == 1:
90 bias = struct.pack("f", btensor.float_val[0])
91 else:
92 bias = btensor.tensor_content
93 f.write(bias)
94
95
96 def dump_depth2space_to_file(self, node, f):
97 assert(node.op == 'DepthToSpace')
98 self.layer_number = self.layer_number + 1
99 block_size = node.attr['block_size'].i
100 np.array([self.op2code[node.op], block_size], dtype=np.uint32).tofile(f)
101 self.converted_nodes.add(node.name)
102
103
104 def generate_layer_number(self):
105 # in current hard code implementation, the layer number is the first data written to the native model file
106 # it is not easy to know it at the beginning time in the general converter, so first do a dry run for compatibility
107 # will be refined later.
108 with open('/tmp/tmp.model', 'wb') as f:
109 self.dump_layers_to_file(f)
110 self.converted_nodes.clear()
111
112
113 def dump_layers_to_file(self, f):
114 for node in self.nodes:
115 if node.name in self.converted_nodes:
116 continue
117 if node.op == 'Conv2D':
118 self.dump_conv2d_to_file(node, f)
119 elif node.op == 'DepthToSpace':
120 self.dump_depth2space_to_file(node, f)
121
122
123 def dump_to_file(self):
124 self.generate_layer_number()
125 with open(self.outfile, 'wb') as f:
126 np.array([self.layer_number], dtype=np.uint32).tofile(f)
127 self.dump_layers_to_file(f)
128
129
130 def generate_name_node_dict(self):
131 for node in self.nodes:
132 self.name_node_dict[node.name] = node
133
134
135 def generate_output_names(self):
136 used_names = []
137 for node in self.nodes:
138 for input in node.input:
139 used_names.append(input)
140
141 for node in self.nodes:
142 if node.name not in used_names:
143 self.output_names.append(node.name)
144
145
146 def remove_identity(self):
147 id_nodes = []
148 id_dict = {}
149 for node in self.nodes:
150 if node.op == 'Identity':
151 name = node.name
152 input = node.input[0]
153 id_nodes.append(node)
154 # do not change the output name
155 if name in self.output_names:
156 self.name_node_dict[input].name = name
157 self.name_node_dict[name] = self.name_node_dict[input]
158 del self.name_node_dict[input]
159 else:
160 id_dict[name] = input
161
162 for idnode in id_nodes:
163 self.nodes.remove(idnode)
164
165 for node in self.nodes:
166 for i in range(len(node.input)):
167 input = node.input[i]
168 if input in id_dict:
169 node.input[i] = id_dict[input]
170
171
172 def generate_edges(self):
173 for node in self.nodes:
174 for input in node.input:
175 if input in self.edges:
176 self.edges[input].append(node)
177 else:
178 self.edges[input] = [node]
179
180
181 def run(self):
182 self.generate_name_node_dict()
183 self.generate_output_names()
184 self.remove_identity()
185 self.generate_edges()
186
187 #check the graph with tensorboard with human eyes
188 #self.dump_for_tensorboard()
189
190 self.dump_to_file()
191
192
193def convert_from_tensorflow(infile, outfile):
194 with open(infile, 'rb') as f:
195 # read the file in .proto format
196 graph_def = tf.GraphDef()
197 graph_def.ParseFromString(f.read())
198 nodes = graph_def.node
199
200 converter = TFConverter(graph_def, nodes, outfile)
201 converter.run()

Keyboard shortcuts

General

Show keyboard shortcuts
?
Focus the current search
/

Issues and pull requests

Open filters
f

Issues, pull requests and Inbox

Select next item
j↓
Select previous item
k↑
Open selected item
Enter
Dismiss filters or clear selection
Esc

Repository code

Go to file
t