TF slice_input_producer不使张量保持同步

Question

我正在将图像读取到我的TF网络中，但是我还需要相关的标签以及它们。

因此，我尝试遵循此答案，但是输出的标签实际上与每个批次中获取的图像都不匹配。

我的图像名称采用格式dir/3.jpg，因此我只是从图像文件名称中提取标签。

truth_filenames_np = ...
truth_filenames_tf = tf.convert_to_tensor(truth_filenames_np)

# get the labels
labels = [f.rsplit("/", 1)[1] for f in truth_filenames_np]

labels_tf = tf.convert_to_tensor(labels)

# *** This line should make sure both input tensors are synced (from my limited understanding)
# My list is also already shuffled, so I set shuffle=False
truth_image_name, truth_label = tf.train.slice_input_producer([truth_filenames_tf, labels_tf], shuffle=False)


truth_image_value = tf.read_file(truth_image_name)
truth_image = tf.image.decode_jpeg(truth_image_value)
truth_image.set_shape([IMAGE_DIM, IMAGE_DIM, 3])
truth_image = tf.cast(truth_image, tf.float32)
truth_image = truth_image/255.0

# Another key step, where I batch them together
truth_images_batch, truth_label_batch = tf.train.batch([truth_image, truth_label], batch_size=mb_size)


with tf.Session() as sess:
    sess.run(tf.global_variables_initializer())

    coord = tf.train.Coordinator()
    threads = tf.train.start_queue_runners(coord=coord)

    for i in range(epochs):
        print "Epoch ", i
        X_truth_batch = truth_images_batch.eval()
        X_label_batch = truth_label_batch.eval()

        # Here I display all the images in this batch, and then I check which file numbers they actually are. 
        # BUT, the images that are displayed don't correspond with what is printed by X_label_batch!
        print X_label_batch
        plot_batch(X_truth_batch)



    coord.request_stop()
    coord.join(threads)

我是在做错什么，还是slice_input_producer实际上没有确保其输入张量得到同步？

在旁边：

我还注意到，当我从tf.train.batch获取批次时，该批次中的元素在我给它的原始列表中彼此相邻，但是批次顺序不在原始顺序中。示例：如果我的数据是[“
dir / 1.jpg”，“ dir / 2.jpg”，“ dir / 3.jpg”，“ dir / 4.jpg”，“ dir / 5.jpg，” dir
/ 6 .jpg“]，那么我可能会得到批处理（batch_size = 2）[” dir / 3.jpg“，” dir / 4.jpg“]，然后是批处理[”
dir / 1.jpg“，” dir / 2 .jpg“]，然后是最后一个。因此，由于订单与批处理订单不匹配，因此甚至很难为标签使用FIFO队列。

Answer 1

这是一个完整的可运行示例，它重现了该问题：

import tensorflow as tf

truth_filenames_np = ['dir/%d.jpg' % j for j in range(66)]
truth_filenames_tf = tf.convert_to_tensor(truth_filenames_np)
# get the labels
labels = [f.rsplit("/", 1)[1] for f in truth_filenames_np]
labels_tf = tf.convert_to_tensor(labels)

# My list is also already shuffled, so I set shuffle=False
truth_image_name, truth_label = tf.train.slice_input_producer(
    [truth_filenames_tf, labels_tf], shuffle=False)

# # Another key step, where I batch them together
# truth_images_batch, truth_label_batch = tf.train.batch(
#     [truth_image_name, truth_label], batch_size=11)

epochs = 7

with tf.Session() as sess:
    sess.run(tf.global_variables_initializer())
    coord = tf.train.Coordinator()
    threads = tf.train.start_queue_runners(coord=coord)
    for i in range(epochs):
        print("Epoch ", i)
        X_truth_batch = truth_image_name.eval()
        X_label_batch = truth_label.eval()
        # Here I display all the images in this batch, and then I check
        # which file numbers they actually are.
        # BUT, the images that are displayed don't correspond with what is
        # printed by X_label_batch!
        print(X_truth_batch)
        print(X_label_batch)
    coord.request_stop()
    coord.join(threads)

打印的内容是：

Epoch  0
b'dir/0.jpg'
b'1.jpg'
Epoch  1
b'dir/2.jpg'
b'3.jpg'
Epoch  2
b'dir/4.jpg'
b'5.jpg'
Epoch  3
b'dir/6.jpg'
b'7.jpg'
Epoch  4
b'dir/8.jpg'
b'9.jpg'
Epoch  5
b'dir/10.jpg'
b'11.jpg'
Epoch  6
b'dir/12.jpg'
b'13.jpg'

因此，基本上每个eval调用都会再次运行该操作！添加批处理对此没有任何影响-只是打印批处理（前11个文件名，后11个标签，依此类推）

我看到的解决方法是：

for i in range(epochs):
    print("Epoch ", i)
    pair = tf.convert_to_tensor([truth_image_name, truth_label]).eval()
    print(pair[0])
    print(pair[1])

正确打印：

Epoch  0
b'dir/0.jpg'
b'0.jpg'
Epoch  1
b'dir/1.jpg'
b'1.jpg'
# ...

但对于违反最不惊奇原则的行为却无能为力。

编辑 ：另一种方法：

import tensorflow as tf

truth_filenames_np = ['dir/%d.jpg' % j for j in range(66)]
truth_filenames_tf = tf.convert_to_tensor(truth_filenames_np)
labels = [f.rsplit("/", 1)[1] for f in truth_filenames_np]
labels_tf = tf.convert_to_tensor(labels)
truth_image_name, truth_label = tf.train.slice_input_producer(
    [truth_filenames_tf, labels_tf], shuffle=False)
epochs = 7
with tf.Session() as sess:
    sess.run(tf.global_variables_initializer())
    tf.train.start_queue_runners(sess=sess)
    for i in range(epochs):
        print("Epoch ", i)
        X_truth_batch, X_label_batch = sess.run(
            [truth_image_name, truth_label])
        print(X_truth_batch)
        print(X_label_batch)

这是一个更好的方法，因为tf.convert_to_tensor并且co只接受相同类型/形状等的张量。

请注意，为简单起见，我删除了协调器，但是会导致警告：

W c：\ tf_jenkins \ home \ workspace \ release-win \ device \ cpu \ os \
windows \ tensorflow \ core \ kernels \ queue_base.cc：294] _0_input_producer
/ input_producer / fraction_of_32_full / fraction_of_32_full：跳过未关闭队列的取消入队尝试

看到这个