Tensorflow - 如何在训练后使用我自己的图像文件

时间:2017-03-23 00:46:51

标签: tensorflow mnist

我现在正在努力学习张量流,所以任何帮助都会受到赞赏。我按照tensorflow网站上发布的mnist代码:https://www.tensorflow.org/get_started/mnist/pros 该模型运行并训练达到99%以上的准确性。我从一个号码的互联网上下载了一个png图像..小时称之为1.png。我现在如何将此图像输入到我训练过的模型中,以确定它是否将其重新识别为一个?到目前为止我看过的YouTube视频都没有,甚至张量流页都没有解释如何做到这一点。我输入什么来让模型检查这个图像?必须有一种方法可以在训练后将单个图像传递给模型,否则就无法到达训练模型的阶段。我使用的总代码如下(这与tensorflow网站上显示的代码相同):

from tensorflow.examples.tutorials.mnist import input_data
mnist = input_data.read_data_sets('MNIST_data', one_hot=True)

import tensorflow as tf
sess = tf.InteractiveSession()

x = tf.placeholder(tf.float32, shape=[None, 784])
y_ = tf.placeholder(tf.float32, shape=[None, 10])

W = tf.Variable(tf.zeros([784,10]))
b = tf.Variable(tf.zeros([10]))

sess.run(tf.global_variables_initializer())

writer = tf.summary.FileWriter('/tmp/mnistworking', graph=sess.graph)


y = tf.matmul(x,W) + b


cross_entropy = tf.reduce_mean(
    tf.nn.softmax_cross_entropy_with_logits(labels=y_, logits=y))

train_step = tf.train.GradientDescentOptimizer(0.5).minimize(cross_entropy)

for _ in range(1000):
  batch = mnist.train.next_batch(100)
  train_step.run(feed_dict={x: batch[0], y_: batch[1]})

correct_prediction = tf.equal(tf.argmax(y, 1), tf.argmax(y_, 1))

accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))

print(accuracy.eval(feed_dict={x: mnist.test.images, y_: mnist.test.labels}))

def weight_variable(shape):
  initial = tf.truncated_normal(shape, stddev=0.1)
  return tf.Variable(initial)

def bias_variable(shape):
  initial = tf.constant(0.1, shape=shape)
  return tf.Variable(initial)

def conv2d(x, W):
  return tf.nn.conv2d(x, W, strides=[1, 1, 1, 1], padding='SAME')

def max_pool_2x2(x):
  return tf.nn.max_pool(x, ksize=[1, 2, 2, 1],
                        strides=[1, 2, 2, 1], padding='SAME')

W_conv1 = weight_variable([5, 5, 1, 32])
b_conv1 = bias_variable([32])

x_image = tf.reshape(x, [-1,28,28,1])

h_conv1 = tf.nn.relu(conv2d(x_image, W_conv1) + b_conv1)
h_pool1 = max_pool_2x2(h_conv1)

W_conv2 = weight_variable([5, 5, 32, 64])
b_conv2 = bias_variable([64])

h_conv2 = tf.nn.relu(conv2d(h_pool1, W_conv2) + b_conv2)
h_pool2 = max_pool_2x2(h_conv2)

W_fc1 = weight_variable([7 * 7 * 64, 1024])
b_fc1 = bias_variable([1024])

h_pool2_flat = tf.reshape(h_pool2, [-1, 7*7*64])
h_fc1 = tf.nn.relu(tf.matmul(h_pool2_flat, W_fc1) + b_fc1)

keep_prob = tf.placeholder(tf.float32)
h_fc1_drop = tf.nn.dropout(h_fc1, keep_prob)

W_fc2 = weight_variable([1024, 10])
b_fc2 = bias_variable([10])

y_conv = tf.matmul(h_fc1_drop, W_fc2) + b_fc2

cross_entropy = tf.reduce_mean(
    tf.nn.softmax_cross_entropy_with_logits(labels=y_, logits=y_conv))
train_step = tf.train.AdamOptimizer(1e-4).minimize(cross_entropy)
correct_prediction = tf.equal(tf.argmax(y_conv,1), tf.argmax(y_,1))
accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
sess.run(tf.global_variables_initializer())
for i in range(17000):
  batch = mnist.train.next_batch(50)
  if i%100 == 0:
    train_accuracy = accuracy.eval(feed_dict={
        x:batch[0], y_: batch[1], keep_prob: 1.0})
    print("step %d, training accuracy %g"%(i, train_accuracy))
  train_step.run(feed_dict={x: batch[0], y_: batch[1], keep_prob: 0.5})

print("test accuracy %g"%accuracy.eval(feed_dict={
    x: mnist.test.images, y_: mnist.test.labels, keep_prob: 1.0}))

1 个答案:

答案 0 :(得分:2)

您需要执行以下操作:

  • 从已保存的检查点恢复模型。有几种方法可以实现这一目标。
  • 将测试图像从磁盘加载到numpy数组中,将其矢量化并重新整形为大小为[1, 784],因为这是此处定义的输入占位符的形状:x = tf.placeholder(tf.float32, shape=[None, 784])。请注意,在这种情况下None代表一个可变的批量大小,因此可以在测试时提供一个数据点,如您所愿。
  • 接下来,让模型完成其工作,即让它预测。为此,您需要获取计算分类的节点,在您发布的代码中似乎为tf.argmax(y_conv, 1)。请注意,您无需将标签提供给模型,因为您在测试期间没有执行培训步骤。

此外,本教程可能对您有所帮助:Tensorflow Mechanics 101