我正在使用 tensorflow 训练“显示和讲述”模型，其中模型自动生成图像的标题。我怎么会收到这个错误。
这是回溯:
TypeError Traceback (most recent call
last)
<ipython-input-15-b6da0a27b701> in <module>()
1 try:
2 #train(.001,False,False) #train from scratch
----> 3 train(.001,True,True) #continue training from pretrained weights @epoch500
4 #train(.001) #train from previously saved weights
5 except KeyboardInterrupt:
<ipython-input-14-39693d0edd0a> in train(learning_rate, continue_training, transfer)
23 n_words = len(wordtoix)
24 maxlen = np.max( [x for x in map(lambda x: len(x.split(' ')), captions) ] )
---> 25 caption_generator = Caption_Generator(dim_in, dim_hidden, dim_embed, batch_size, maxlen+2, n_words, init_b)
26
27 loss, image, sentence, mask = caption_generator.build_model()
<ipython-input-12-7ef491a16183> in __init__(self, dim_in, dim_embed, dim_hidden, batch_size, n_lstm_steps, n_words, init_b)
11 # declare the variables to be used for our word embeddings
12 with tf.device("/cpu:0"):
---> 13 self.word_embedding = tf.get_variable("word_embedding", tf.random_uniform([self.n_words, self.dim_embed], -0.1, 0.1))
14
15 self.embedding_bias = tf.get_variable("embedding_bias", tf.zeros([dim_embed]))
/home/niraj/anaconda2/lib/python2.7/site-packages/tensorflow/python/ops/variable_scope.pyc in get_variable(name, shape, dtype, initializer, regularizer, trainable, collections, caching_device, partitioner, validate_shape, use_resource, custom_getter)
1063 collections=collections, caching_device=caching_device,
1064 partitioner=partitioner, validate_shape=validate_shape,
-> 1065 use_resource=use_resource, custom_getter=custom_getter)
1066 get_variable_or_local_docstring = (
1067 """%s
/home/niraj/anaconda2/lib/python2.7/site-packages/tensorflow/python/ops/variable_scope.pyc in get_variable(self, var_store, name, shape, dtype, initializer, regularizer, reuse, trainable, collections, caching_device, partitioner, validate_shape, use_resource, custom_getter)
960 collections=collections, caching_device=caching_device,
961 partitioner=partitioner, validate_shape=validate_shape,
--> 962 use_resource=use_resource, custom_getter=custom_getter)
963
964 def _get_partitioned_variable(self,
/home/niraj/anaconda2/lib/python2.7/site-packages/tensorflow/python/ops/variable_scope.pyc in get_variable(self, name, shape, dtype, initializer, regularizer, reuse, trainable, collections, caching_device, partitioner, validate_shape, use_resource, custom_getter)
365 reuse=reuse, trainable=trainable, collections=collections,
366 caching_device=caching_device, partitioner=partitioner,
--> 367 validate_shape=validate_shape, use_resource=use_resource)
368
369 def _get_partitioned_variable(
/home/niraj/anaconda2/lib/python2.7/site-packages/tensorflow/python/ops/variable_scope.pyc in _true_getter(name, shape, dtype, initializer, regularizer, reuse, trainable, collections, caching_device, partitioner, validate_shape, use_resource)
301 trainable=True, collections=None, caching_device=None,
302 partitioner=None, validate_shape=True, use_resource=None):
--> 303 is_scalar = shape is not None and not shape
304 # Partitioned variable case
305 if partitioner is not None and not is_scalar:
/home/niraj/anaconda2/lib/python2.7/site-packages/tensorflow/python/framework/ops.pyc in __nonzero__(self)
511 `TypeError`.
512 """
--> 513 raise TypeError("Using a `tf.Tensor` as a Python `bool` is not allowed. "
514 "Use `if t is not None:` instead of `if t:` to test if a "
515 "tensor is defined, and use TensorFlow ops such as "
TypeError:不允许将 tf.Tensor 用作 Python bool。使用 if t is not None: 而不是 if t: 来测试是否定义了张量，并使用 TensorFlow ops 如 tf.cond 来执行以值为条件的子图张量的。
代码如下:
def preProBuildWordVocab(sentence_iterator, word_count_threshold=30): # function from Andre Karpathy's NeuralTalk
print('preprocessing %d word vocab' % (word_count_threshold, ))
word_counts = {}
nsents = 0
for sent in sentence_iterator:
nsents += 1
for w in sent.lower().split(' '):
word_counts[w] = word_counts.get(w, 0) + 1
vocab = [w for w in word_counts if word_counts[w] >= word_count_threshold]
print('preprocessed words %d -> %d' % (len(word_counts), len(vocab)))
ixtoword = {}
ixtoword[0] = '.'
wordtoix = {}
wordtoix['#START#'] = 0
ix = 1
for w in vocab:
wordtoix[w] = ix
ixtoword[ix] = w
ix += 1
word_counts['.'] = nsents
bias_init_vector = np.array([1.0*word_counts[ixtoword[i]] for i in ixtoword])
bias_init_vector /= np.sum(bias_init_vector)
bias_init_vector = np.log(bias_init_vector)
bias_init_vector -= np.max(bias_init_vector)
return wordtoix, ixtoword, bias_init_vector.astype(np.float32)
class Caption_Generator():
def __init__(self, dim_in, dim_embed, dim_hidden, batch_size, n_lstm_steps, n_words, init_b):
self.dim_in = dim_in
self.dim_embed = dim_embed
self.dim_hidden = dim_hidden
self.batch_size = batch_size
self.n_lstm_steps = n_lstm_steps
self.n_words = n_words
# declare the variables to be used for our word embeddings
with tf.device("/cpu:0"):
self.word_embedding = tf.get_variable("word_embedding", tf.random_uniform([self.n_words, self.dim_embed], -0.1, 0.1))
self.embedding_bias = tf.get_variable("embedding_bias", tf.zeros([dim_embed]))
# declare the LSTM itself
self.lstm = tf.contrib.rnn.BasicLSTMCell(dim_hidden)
# declare the variables to be used to embed the image feature embedding to the word embedding space
self.img_embedding = tf.get_variable("img_embedding", tf.random_uniform([dim_in, dim_hidden], -0.1, 0.1))
self.img_embedding_bias = tf.get_variable("img_embedding_bias", tf.zeros([dim_hidden]))
# declare the variables to go from an LSTM output to a word encoding output
self.word_encoding = tf.get_variable("word_encoding", tf.random_uniform([dim_hidden, n_words], -0.1, 0.1))
# initialize this bias variable from the preProBuildWordVocab output
self.word_encoding_bias = tf.get_variable("word_encoding_bias", init_b)
def build_model(self):
# declaring the placeholders for our extracted image feature vectors, our caption, and our mask
# (describes how long our caption is with an array of 0/1 values of length `maxlen`
img = tf.placeholder(tf.float32, [self.batch_size, self.dim_in])
caption_placeholder = tf.placeholder(tf.int32, [self.batch_size, self.n_lstm_steps])
mask = tf.placeholder(tf.float32, [self.batch_size, self.n_lstm_steps])
# getting an initial LSTM embedding from our image_imbedding
image_embedding = tf.matmul(img, self.img_embedding) + self.img_embedding_bias
# setting initial state of our LSTM
state = self.lstm.zero_state(self.batch_size, dtype=tf.float32)
total_loss = 0.0
with tf.variable_scope("RNN"):
for i in range(self.n_lstm_steps):
if i > 0:
#if this isn’t the first iteration of our LSTM we need to get the word_embedding corresponding
# to the (i-1)th word in our caption
with tf.device("/cpu:0"):
current_embedding = tf.nn.embedding_lookup(self.word_embedding, caption_placeholder[:,i-1]) + self.embedding_bias
else:
#if this is the first iteration of our LSTM we utilize the embedded image as our input
current_embedding = image_embedding
if i > 0:
# allows us to reuse the LSTM tensor variable on each iteration
tf.get_variable_scope().reuse_variables()
out, state = self.lstm(current_embedding, state)
#out, state = self.tf.nn.dynamic_rnn(current_embedding, state)
if i > 0:
#get the one-hot representation of the next word in our caption
labels = tf.expand_dims(caption_placeholder[:, i], 1)
ix_range=tf.range(0, self.batch_size, 1)
ixs = tf.expand_dims(ix_range, 1)
concat = tf.concat([ixs, labels],1)
onehot = tf.sparse_to_dense(
concat, tf.stack([self.batch_size, self.n_words]), 1.0, 0.0)
#perform a softmax classification to generate the next word in the caption
logit = tf.matmul(out, self.word_encoding) + self.word_encoding_bias
xentropy = tf.nn.softmax_cross_entropy_with_logits(logits=logit, labels=onehot)
xentropy = xentropy * mask[:,i]
loss = tf.reduce_sum(xentropy)
total_loss += loss
total_loss = total_loss / tf.reduce_sum(mask[:,1:])
return total_loss, img, caption_placeholder, mask
### Parameters ###
dim_embed = 256
dim_hidden = 256
dim_in = 4096
batch_size = 128
momentum = 0.9
n_epochs = 150
def train(learning_rate=0.001, continue_training=False, transfer=True):
tf.reset_default_graph()
feats, captions = get_data(annotation_path, feature_path)
wordtoix, ixtoword, init_b = preProBuildWordVocab(captions)
np.save('data/ixtoword', ixtoword)
index = (np.arange(len(feats)).astype(int))
np.random.shuffle(index)
sess = tf.InteractiveSession()
n_words = len(wordtoix)
maxlen = np.max( [x for x in map(lambda x: len(x.split(' ')), captions) ] )
caption_generator = Caption_Generator(dim_in, dim_hidden, dim_embed, batch_size, maxlen+2, n_words, init_b)
loss, image, sentence, mask = caption_generator.build_model()
saver = tf.train.Saver(max_to_keep=100)
global_step=tf.Variable(0,trainable=False)
learning_rate = tf.train.exponential_decay(learning_rate, global_step,
int(len(index)/batch_size), 0.95)
train_op = tf.train.AdamOptimizer(learning_rate).minimize(loss)
tf.global_variables_initializer().run()
if continue_training:
if not transfer:
saver.restore(sess,tf.train.latest_checkpoint(model_path))
else:
saver.restore(sess,tf.train.latest_checkpoint(model_path_transfer))
losses=[]
for epoch in range(n_epochs):
for start, end in zip( range(0, len(index), batch_size), range(batch_size, len(index), batch_size)):
current_feats = feats[index[start:end]]
current_captions = captions[index[start:end]]
current_caption_ind = [x for x in map(lambda cap: [wordtoix[word] for word in cap.lower().split(' ')[:-1] if word in wordtoix], current_captions)]
current_caption_matrix = sequence.pad_sequences(current_caption_ind, padding='post', maxlen=maxlen+1)
current_caption_matrix = np.hstack( [np.full( (len(current_caption_matrix),1), 0), current_caption_matrix] )
current_mask_matrix = np.zeros((current_caption_matrix.shape[0], current_caption_matrix.shape[1]))
nonzeros = np.array([x for x in map(lambda x: (x != 0).sum()+2, current_caption_matrix )])
for ind, row in enumerate(current_mask_matrix):
row[:nonzeros[ind]] = 1
_, loss_value = sess.run([train_op, loss], feed_dict={
image: current_feats.astype(np.float32),
sentence : current_caption_matrix.astype(np.int32),
mask : current_mask_matrix.astype(np.float32)
})
print("Current Cost: ", loss_value, "\t Epoch {}/{}".format(epoch, n_epochs), "\t Iter {}/{}".format(start,len(feats)))
print("Saving the model from epoch: ", epoch)
saver.save(sess, os.path.join(model_path, 'model'), global_step=epoch)
请您参考如下方法:
问题源于将 tf.Tensor 作为 tf.get_variable(name, shape=None, ...) 的 shape 参数传递在这条线上:
self.word_embedding = tf.get_variable("word_embedding", tf.random_uniform([self.n_words, self.dim_embed], -0.1, 0.1))
我怀疑您打算将随机张量作为 initializer 参数传递。解决这个问题的最简单方法是为参数指定一个名称:
self.word_embedding = tf.get_variable(
"word_embedding",
initializer=tf.random_uniform([self.n_words, self.dim_embed], -0.1, 0.1))
看起来您对 tf.get_variable() 的所有调用都需要类似的修复。
