我是 Tensorflow 和机器学习的新手,正在尝试使用 Tensorflow 和我的自定义输入数据来使用 CNN。但我收到下面附加的错误。
数据或图像大小为 28x28,带有 15 个标签。 我没有在这个脚本中得到 numpy reshape 的东西或错误。
非常感谢您的帮助。
import tensorflow as tf
import os
import skimage.data
import numpy as np
import random
def load_data(data_directory):
directories = [d for d in os.listdir(data_directory)
if os.path.isdir(os.path.join(data_directory, d))]
labels = []
images = []
for d in directories:
label_directory = os.path.join(data_directory, d)
file_names = [os.path.join(label_directory, f)
for f in os.listdir(label_directory)
if f.endswith(".jpg")]
for f in file_names:
images.append(skimage.data.imread(f))
labels.append(d)
print(str(d)+' Completed')
return images, labels
ROOT_PATH = "H:\Testing\TrainingData"
train_data_directory = os.path.join(ROOT_PATH, "Training")
test_data_directory = os.path.join(ROOT_PATH, "Testing")
print('Loading Data...')
images, labels = load_data(train_data_directory)
print('Data has been Loaded')
n_classes = 15
training_examples = 10500
test_examples = 4500
batch_size = 128
x = tf.placeholder('float', [None, 784])
y = tf.placeholder('float')
def conv2d(x, W):
return tf.nn.conv2d(x, W, strides=[1,1,1,1], padding='SAME')
def maxpool2d(x):
return tf.nn.max_pool(x, ksize=[1,2,2,1], strides=[1,2,2,1], padding='SAME')
def neural_network_model(x):
weights = {'W_Conv1':tf.Variable(tf.random_normal([5,5,1,32])),
'W_Conv2':tf.Variable(tf.random_normal([5,5,32,64])),
'W_FC':tf.Variable(tf.random_normal([7*7*64, 1024])),
'Output':tf.Variable(tf.random_normal([1024, n_classes]))}
biases = {'B_Conv1':tf.Variable(tf.random_normal([32])),
'B_Conv2':tf.Variable(tf.random_normal([64])),
'B_FC':tf.Variable(tf.random_normal([1024])),
'Output':tf.Variable(tf.random_normal([n_classes]))}
x = tf.reshape(x, shape=[-1,28,28,1])
conv1 = conv2d(x, weights['W_Conv1'])
conv1 = maxpool2d(conv1)
conv2 = conv2d(conv1, weights['W_Conv2'])
conv2 = maxpool2d(conv2)
fc = tf.reshape(conv2, [-1, 7*7*64])
fc = tf.nn.relu(tf.matmul(fc, weights['W_FC'])+biases['B_FC'])
output = tf.matmul(fc, weights['Output'])+biases['Output']
return output
def next_batch(num, data, labels):
idx = np.arange(0 , len(data))
np.random.shuffle(idx)
idx = idx[:num]
data_shuffle = [data[ i] for i in idx]
labels_shuffle = [labels[ i] for i in idx]
return np.asarray(data_shuffle), np.asarray(labels_shuffle)
def train_neural_network(x):
prediction = neural_network_model(x)
cost = tf.reduce_mean( tf.nn.softmax_cross_entropy_with_logits(logits=prediction, labels=y) )
optimizer = tf.train.AdamOptimizer().minimize(cost)
hm_epochs = 10
with tf.Session() as sess:
# OLD:
#sess.run(tf.initialize_all_variables())
# NEW:
sess.run(tf.global_variables_initializer())
for epoch in range(hm_epochs):
epoch_loss = 0
for _ in range(int(training_examples/batch_size)):
epoch_x, epoch_y = next_batch(batch_size, images, labels)
_, c = sess.run([optimizer, cost], feed_dict={x: epoch_x, y: epoch_y})
epoch_loss += c
print('Epoch', epoch, 'completed out of',hm_epochs,'loss:',epoch_loss)
correct = tf.equal(tf.argmax(prediction, 1), tf.argmax(y, 1))
accuracy = tf.reduce_mean(tf.cast(correct, 'float'))
print('Accuracy:',accuracy.eval({x: images, y: labels}))
print('Training Neural Network...')
train_neural_network(x)
我做错了什么?需要修复什么以及如何修复 numpy 数组的形状?
最佳答案
如果仔细观察,您会发现有两个 x
占位符:
x = tf.placeholder('float', [None, 784]) # global
...
x = tf.reshape(x, shape=[-1,28,28,1]) # in neural_network_model
其中一个在函数作用域内,因此在 train_neural_network
中不可见,所以 TensorFlow 采用 [?, 784]
的那个形状。你应该摆脱其中之一。
另请注意,您的训练数据的等级为 3,即 [batch_size, 28, 28]
,因此它与这些占位符中的任何一个都不直接兼容。
将其输入第一个 x
,取epoch_x.reshape([-1, 784])
。对于第二个占位符(使其可见后),请使用 epoch_x.reshape([-1, 28, 28, 1])
.
关于numpy - ValueError : Cannot feed value of shape (128, 28, 28) 对于张量 'Placeholder:0' ,其形状为 '(?, 784)',我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48960010/