根据现有检查点定义 TensorFlow 网络密钥名称

Define TensorFlow network key names according to an existing checkpoint

我使用 Nvidia DIGITS 训练了 LeNet-gray-28x28 图像检测 Tensorflow 模型,得到了我期望的结果。 现在,我必须 class 验证 DIGITS 之外的一些图像,我想使用我训练过的模型。

所以我得到了 DIGITS 使用的 LeNet 模型,我创建了一个 class 来使用它:

import tensorflow as tf
import tensorflow.contrib.slim as slim
import tflearn
from tflearn.layers.core import input_data


class LeNetModel():

    def gray28(self, nclasses):
        x = input_data(shape=[None, 28, 28, 1])
        # scale (divide by MNIST std)
        # x = x * 0.0125
        with slim.arg_scope([slim.conv2d, slim.fully_connected],
                            weights_initializer=tf.contrib.layers.xavier_initializer(),
                            weights_regularizer=slim.l2_regularizer(0.0005)):
            model = slim.conv2d(x, 20, [5, 5], padding='VALID', scope='conv1')
            model = slim.max_pool2d(model, [2, 2], padding='VALID', scope='pool1')
            model = slim.conv2d(model, 50, [5, 5], padding='VALID', scope='conv2')
            model = slim.max_pool2d(model, [2, 2], padding='VALID', scope='pool2')
            model = slim.flatten(model)
            model = slim.fully_connected(model, 500, scope='fc1')
            model = slim.dropout(model, 0.5, is_training=False, scope='do1')
            model = slim.fully_connected(model, nclasses, activation_fn=None, scope='fc2')

            return tflearn.DNN(model)

我从 DIGITS 下载我的模型并使用(在另一个文件中)实例化它:

self.ballmodel = LeNetModel().gray28(2)
self.ballmodel.load("src/perftrack/prototype/models/ball/snapshot_5.ckpt")

但是,当我启动我的脚本时,出现了这些异常:

2017-11-26 14:55:50.330524: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key conv1/biases not found in checkpoint
2017-11-26 14:55:50.330948: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key Global_Step not found in checkpoint
2017-11-26 14:55:50.331270: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key is_training not found in checkpoint
2017-11-26 14:55:50.331564: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key conv2/weights not found in checkpoint
2017-11-26 14:55:50.332823: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key conv1/weights not found in checkpoint
2017-11-26 14:55:50.332891: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key conv2/biases not found in checkpoint
2017-11-26 14:55:50.333620: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key fc2/weights not found in checkpoint
2017-11-26 14:55:50.334021: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key fc1/weights not found in checkpoint
2017-11-26 14:55:50.334173: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key fc1/biases not found in checkpoint
2017-11-26 14:55:50.334431: W tensorflow/core/framework/op_kernel.cc:1192] Not found: Key fc2/biases not found in checkpoint
...
raise type(e)(node_def, op, message)
tensorflow.python.framework.errors_impl.NotFoundError: Key conv1/biases not found in checkpoint
         [[Node: save_1/RestoreV2_1 = RestoreV2[dtypes=[DT_FLOAT], _device="/job:localhost/replica:0/task:0/cpu:0"](_arg_save_1/Const_0_0, save_1/RestoreV2_1/tensor_names, save_1/RestoreV2_1/shape_and_slices)]]
         [[Node: save_1/RestoreV2_1/_19 = _Recv[client_terminated=false, recv_device="/job:localhost/replica:0/task:0/gpu:0", send_device="/job:localhost/replica:0/task:0/cpu:0", send_device_incarnation=1, tensor_name="edge_38_save_1/RestoreV2_1", tensor_type=DT_FLOAT, _device="/job:localhost/replica:0/task:0/gpu:0"]()]]

所以我使用 https://github.com/tensorflow/tensorflow/blob/master/tensorflow/python/tools/inspect_checkpoint.py 脚本来检查我的检查点包含的键名,我得到类似的东西:

model/conv1/biases
model/conv2/weights
...

所以我重写了我的网络,手动添加模型/前缀:

                model = slim.conv2d(x, 20, [5, 5], padding='VALID', scope='model/conv1')
                model = slim.max_pool2d(model, [2, 2], padding='VALID', scope='model/pool1')
                model = slim.conv2d(model, 50, [5, 5], padding='VALID', scope='model/conv2')
                model = slim.max_pool2d(model, [2, 2], padding='VALID', scope='model/pool2')
                model = slim.flatten(model)
                model = slim.fully_connected(model, 500, scope='model/fc1')
                model = slim.dropout(model, 0.5, is_training=False, scope='model/do1')
                model = slim.fully_connected(model, nclasses, 

它修复了一些丢失的键警告但是:

所以我的问题是:如何在我的网络中重新定义这些密钥名称以匹配我在我的检查点中找到的密钥名称?

因为我的问题主要是对TensorFlow的理解不好,翻了翻官方文档,也找到了一些答案。

首先,我结合使用contrib/slim和contrib/tflearn,即使可以,也不是很相关。所以我只使用 slim 重写了网络:

import tensorflow as tf
import tensorflow.contrib.slim as slim


class LeNetModel():

    def gray28(self, nclasses):
        # x = input_data(shape=[None, 28, 28, 1])
        x = tf.placeholder(tf.float32, shape=[1, 28, 28], name="x")
        rs = tf.reshape(x, shape=[-1, 28, 28, 1])
        # scale (divide by MNIST std)
        # x = x * 0.0125
        with slim.arg_scope([slim.conv2d, slim.fully_connected],
                            weights_initializer=tf.contrib.layers.xavier_initializer(),
                            weights_regularizer=slim.l2_regularizer(0.0005)):
            model = slim.conv2d(rs, 20, [5, 5], padding='VALID', scope='conv1')
            model = slim.max_pool2d(model, [2, 2], padding='VALID', scope='pool1')
            model = slim.conv2d(model, 50, [5, 5], padding='VALID', scope='conv2')
            model = slim.max_pool2d(model, [2, 2], padding='VALID', scope='pool2')
            model = slim.flatten(model)
            model = slim.fully_connected(model, 500, scope='fc1')
            model = slim.dropout(model, 0.5, is_training=True, scope='do1')
            model = slim.fully_connected(model, nclasses, activation_fn=None, scope='fc2')

            return x, model

我 return x 占位符和模型,我用它来加载 DIGITS 预训练模型(检查点):

import tensorflow as tf
import tensorflow.contrib.slim as slim
import cv2
from models.lenet import LeNetModel

# Helper function to load/resize images
def image(path):
    img = cv2.imread(path, 0)
    return cv2.resize(img, dsize=(28,28))

# Define a function that adds the model/ prefix to all variables :
def name_in_checkpoint(var):
  return 'model/' + var.op.name

#Instantiate the model
x, model = LeNetModel().gray28(2)

# Define the variables to restore :
# Exclude the "is_training" that I don't care about
variables_to_restore = slim.get_variables_to_restore(exclude=["is_training"])
# Rename the other variables with the function name_in_checkpoint
variables_to_restore = {name_in_checkpoint(var):var for var in variables_to_restore}

# Create a Saver to restore the checkpoint, given the variables
restorer = tf.train.Saver(variables_to_restore)

#Launch a session to restore the checkpoint and try to infer some images :
with tf.Session() as sess:
    # Restore variables from disk.
    restorer.restore(sess, "src/prototype/models/snapshot_5.ckpt")
    print("Model restored.")
    print(sess.run(model, feed_dict={x:[image("/home/damien/Vidéos/1/positives/img/1-img143.jpg")]}))
    print(sess.run(model, feed_dict={x:[image("/home/damien/Vidéos/0/positives/img/1-img1.jpg")]}))

而且有效!