技巧：使用freeze_graph將SavedModel生成的模型合并成一個pb文件
在訓(xùn)練mnist模型的時候，增加一個參數(shù)昨寞，可以在訓(xùn)練完畢后導(dǎo)出SavedModel
python mnist.py --export_dir /tmp/mnist_saved_model
訓(xùn)練完成后夜涕，會以以下文件結(jié)構(gòu)在/tmp/mnist_saved_model生成模型文件
── 1530159051
├── saved_model.pb
└── variables
├── variables.data-00000-of-00001
└── variables.index
saved_model.pb 保存的是計算圖信息
variables 保存的是計算中的變量信息
我的目是想要在Android上運行測試這個模型拴事，但是從官方給的Demo中可以看到募逞，所加載的模型都是單個文件越败，暫時也沒看到加載SavedModel的接口
為了方便Android平臺使用，用freeze_graph腳本將SavedModel合并
查看這個腳本的源碼拆祈，在最開頭可以看到
Converts checkpoint variables into Const ops in a standalone GraphDef file.
This script is designed to take a GraphDef proto, a SaverDef proto, and a set of
variable values stored in a checkpoint file, and output a GraphDef with all of
the variable ops converted into const ops containing the values of the
variables.
It's useful to do this when we need to load a single file in C++, especially in
environments like mobile or embedded where we may not have access to the
RestoreTensor ops and file loading calls that they rely on.
這個腳本就是用來將變量轉(zhuǎn)換為常量合并到到計算圖中的
具體怎么使用呢恨闪？
腳本中給出的例子是這樣的：
bazel build tensorflow/python/tools:freeze_graph && \
bazel-bin/tensorflow/python/tools/freeze_graph \
--input_graph=some_graph_def.pb \
--input_checkpoint=model.ckpt-8361242 \
--output_graph=/tmp/frozen_graph.pb --output_node_names=softmax
因為我電腦是完整安裝了tensorflow的，所以可以直接使用freeze_graph而不用通過bazel去創(chuàng)建freeze_graph
freeze_graph --input_graph=saved_model.pb --input_checkpoint=variables/variables --output_graph=merge_graph.pb --output_node_names=softmax
執(zhí)行放坏，然后掛了
from ._conv import register_converters as _register_converters
Traceback (most recent call last):
File "/home/xxx/anaconda2/bin/freeze_graph", line 11, in <module>
sys.exit(run_main())
File "/home/xxx/anaconda2/lib/python2.7/site-packages/tensorflow/python/tools/freeze_graph.py", line 379, in run_main
app.run(main=my_main, argv=[sys.argv[0]] + unparsed)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/tensorflow/python/platform/app.py", line 125, in run
_sys.exit(main(argv))
File "/home/xxx/anaconda2/lib/python2.7/site-packages/tensorflow/python/tools/freeze_graph.py", line 378, in <lambda>
my_main = lambda unused_args: main(unused_args, flags)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/tensorflow/python/tools/freeze_graph.py", line 272, in main
flags.saved_model_tags, checkpoint_version)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/tensorflow/python/tools/freeze_graph.py", line 231, in freeze_graph
input_graph_def = _parse_input_graph_proto(input_graph, input_binary)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/tensorflow/python/tools/freeze_graph.py", line 174, in _parse_input_graph_proto
text_format.Merge(f.read(), input_graph_def)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/google/protobuf/text_format.py", line 536, in Merge
descriptor_pool=descriptor_pool)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/google/protobuf/text_format.py", line 590, in MergeLines
return parser.MergeLines(lines, message)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/google/protobuf/text_format.py", line 623, in MergeLines
self._ParseOrMerge(lines, message)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/google/protobuf/text_format.py", line 638, in _ParseOrMerge
self._MergeField(tokenizer, message)
File "/home/xxx/anaconda2/lib/python2.7/site-packages/google/protobuf/text_format.py", line 706, in _MergeField
name = tokenizer.ConsumeIdentifierOrNumber()
File "/home/xxx/anaconda2/lib/python2.7/site-packages/google/protobuf/text_format.py", line 1166, in ConsumeIdentifierOrNumber
raise self.ParseError('Expected identifier or number, got %s.' % result)
google.protobuf.text_format.ParseError: 1:1 : Expected identifier or number, got.
什么鬼錯咙咽，Expected identifier or number 字面意思應(yīng)該是傳入的文件少了點什么東西
再看看freeze_graph腳本的源碼
在run_main()函數(shù)里看到了一個參數(shù)
parser.add_argument(
"--input_saved_model_dir",
type=str,
default="",
help="Path to the dir with TensorFlow \'SavedModel\' file and variables.")
原來是用錯參數(shù)了，噗...
修改一下命令
freeze_graph \
--input_saved_model_dir=1530159051 \
--output_node_names=Softmax,ArgMax \
--output_graph=merge1_graph.pb
再執(zhí)行淤年，屁都沒冒一個钧敞，說明執(zhí)行成功了，沒報錯麸粮，哈哈
看下指定的輸出文件有沒有生成
ww3:~/source/TFmodels_out/mnist_saved_model$ ls -l
總用量 12804
drwxr-xr-x 3 ww3 ww3 4096 6月 28 12:10 1530159051
-rw-rw-r-- 1 ww3 ww3 13105521 6月 28 17:58 merge1_graph.pb
嗯...具體這個文件能不能直接用還有待研究
