python - tensorflow中TFRecord是怎么用的？

问题描述

怎么把下面的代码中的mnist数据集换成TFRecord

假设TFRecord数据集已经准备好，train.tfrecords 和 test.tfrecords 都在当前py的目录下

已经有TFRecord的读取代码。

def read_and_decode(filename): filename_queue = tf.train.string_input_producer([filename]) reader = tf.TFRecordReader() _, serialized_example = reader.read(filename_queue) features = tf.parse_single_example(serialized_example, features={ ’label’: tf.FixedLenFeature([], tf.int64), ’img_raw’: tf.FixedLenFeature([], tf.string), }) img = tf.decode_raw(features[’img_raw’], tf.uint8) img = tf.reshape(img, [512, 288, 3]) img = tf.cast(img, tf.float32) * (1. / 255) - 0.5 label = tf.cast(features[’label’], tf.int32) return img, label

from tensorflow.examples.tutorials.mnist import input_dataimport tensorflow as tfmnist = input_data.read_data_sets('/tmp/tensorflow/mnist/input_data', one_hot=True)# Parameterslearning_rate = 0.001training_iters = 200000batch_size = 64display_step = 20# Network Parametersn_input = 784 # MNIST data input (img shape: 28*28)n_classes = 10 # MNIST total classes (0-9 digits)dropout = 0.75 # Dropout, probability to keep units# tf Graph inputx = tf.placeholder(tf.float32, [None, n_input])y = tf.placeholder(tf.float32, [None, n_classes])keep_prob = tf.placeholder(tf.float32) # dropout (keep probability)def init_weights(shape): return tf.Variable(tf.random_normal(shape, stddev=0.01))# Create custom modeldef conv2d(name, l_input, w, b): return tf.nn.relu(tf.nn.bias_add(tf.nn.conv2d(l_input, w, strides=[1, 1, 1, 1], padding=’SAME’), b), name=name)def max_pool(name, l_input, k): return tf.nn.max_pool(l_input, ksize=[1, k, k, 1], strides=[1, k, k, 1], padding=’SAME’, name=name)def norm(name, l_input, lsize=4): return tf.nn.lrn(l_input, lsize, bias=1.0, alpha=0.001 / 9.0, beta=0.75, name=name)def dnn(_x, _weights, _biases, _dropout): _x = tf.nn.dropout(_x, _dropout) d1 = tf.nn.relu(tf.nn.bias_add(tf.matmul(_x, _weights[’wd1’]), _biases[’bd1’]), name='d1') d2x = tf.nn.dropout(d1, _dropout) d2 = tf.nn.relu(tf.nn.bias_add(tf.matmul(d2x, _weights[’wd2’]), _biases[’bd2’]), name='d2') dout = tf.nn.dropout(d2, _dropout) out = tf.matmul(dout, _weights[’out’]) + _biases[’out’] return out# Store layers weight & biasweights = { ’wd1’: tf.Variable(tf.random_normal([784, 600], stddev=0.01)), ’wd2’: tf.Variable(tf.random_normal([600, 480], stddev=0.01)), ’out’: tf.Variable(tf.random_normal([480, 10]))}biases = { ’bd1’: tf.Variable(tf.random_normal([600])), ’bd2’: tf.Variable(tf.random_normal([480])), ’out’: tf.Variable(tf.random_normal([10]))}# Construct modelpred = dnn(x, weights, biases, keep_prob)# Define loss and optimizercost = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(pred, y))optimizer = tf.train.AdamOptimizer(learning_rate=learning_rate).minimize(cost)# Evaluate modelcorrect_pred = tf.equal(tf.argmax(pred, 1), tf.argmax(y, 1))accuracy = tf.reduce_mean(tf.cast(correct_pred, tf.float32))# Initializing the variablesinit = tf.global_variables_initializer()#tf.summary.scalar('loss', cost)tf.summary.scalar('accuracy', accuracy)# Merge all summaries to a single operatormerged_summary_op = tf.summary.merge_all()# Launch the graphwith tf.Session() as sess: sess.run(init) summary_writer = tf.summary.FileWriter(’/tmp/logs/ex12_dnn’, graph=sess.graph) step = 1 # Keep training until reach max iterations while step * batch_size < training_iters:batch_xs, batch_ys = mnist.train.next_batch(batch_size)# Fit training using batch datasess.run(optimizer, feed_dict={x: batch_xs, y: batch_ys, keep_prob: dropout})if step % display_step == 0: # Calculate batch accuracy acc = sess.run(accuracy, feed_dict={x: batch_xs, y: batch_ys, keep_prob: 1.}) # Calculate batch loss loss = sess.run(cost, feed_dict={x: batch_xs, y: batch_ys, keep_prob: 1.}) print('Iter ' + str(step * batch_size) + ', Minibatch Loss= ' + '{:.6f}'.format(loss) + ', Training Accuracy= ' + '{:.5f}'.format(acc)) summary_str = sess.run(merged_summary_op, feed_dict={x: batch_xs, y: batch_ys, keep_prob: 1.}) summary_writer.add_summary(summary_str, step)step += 1 print('Optimization Finished!') # Calculate accuracy for 256 mnist test images print('Testing Accuracy:', sess.run(accuracy, feed_dict={x: mnist.test.images[:256], y: mnist.test.labels[:256], keep_prob: 1.})) # 98%

不知道具体怎么使用， 改了几次执行都报错

错误类似

ValueError: Only call `softmax_cross_entropy_with_logits` with named arguments (labels=..., logits=..., ...)

问题解答

不知道是否理解你的意思，这段代码mnist = input_data.read_data_sets('/tmp/tensorflow/mnist/input_data', one_hot=True)读取的就是mnist数据，你把它换掉，然后在使用TFRecord的读取代码读取TFRecord数据，将下面训练网络的代码中的mnist也换掉，同时确保你使用的卷积操作参数要和TFRecord数据对应。