clock_data.py 文件源码

def read_image_and_label(image_label_q):
    # Returns three Tensors: the decoded PNG image, the hour, and the minute.
    filename, hour_str, minute_str = tf.decode_csv(
        image_label_q.dequeue(), [[""], [""], [""]], " ")
    file_contents = tf.read_file(filename)

    # Decode image from PNG, and cast it to a float.
    example = tf.image.decode_png(file_contents, channels=image_channels)
    image = tf.cast(example, tf.float32)

    # Set the tensor size manually from the image.
    image.set_shape([image_size, image_size, image_channels])

    # Do per-image whitening (zero mean, unit standard deviation). Without this,
    # the learning algorithm diverges almost immediately because the gradient is
    # too big.
    image = tf.image.per_image_whitening(image)

    # The label should be an integer.
    hour = tf.string_to_number(hour_str, out_type=tf.int32)
    minute = tf.string_to_number(minute_str, out_type=tf.int32)

    return image, hour, minute