首页 > 解决方案 > 用于图像增强的 TensorFlow 使 keras 无法工作

问题描述

我正在实施 CNN 进行图像分类;我使用 keras 采用了一个随机的 CNN 架构

import keras
from keras.models import Sequential,Input,Model
from keras.layers import Dense, Dropout, Flatten
from keras.layers import Conv2D, MaxPooling2D
from keras.layers.normalization import BatchNormalization
from keras.layers.advanced_activations import LeakyReLU

model = Sequential()
model.add(Conv2D(filters=32, kernel_size=(3, 3), activation="relu", input_shape=(n,n,1)))
model.add(MaxPooling2D(pool_size=(2, 2)))
model.add(Dropout(0.25))
model.add(Conv2D(filters=64, kernel_size=(5, 5), activation='relu'))
model.add(MaxPooling2D(pool_size=(2, 2)))
model.add(Dropout(0.25))
model.add(Flatten())
model.add(Dense(num_classes, activation='softmax'))

model.compile(loss=keras.losses.categorical_crossentropy, optimizer=keras.optimizers.Adam(),metrics=['accuracy'])



train = model.fit(train_X, train_label, batch_size=batch_size,epochs=epochs,verbose=1,validation_data=(valid_X, valid_label))

我正在尝试使用 tensorflow 的代码进行图像增强,我更喜欢此代码而不是使用 keras ImageDataGenerator 进行数据增强,因为它让我更灵活。



import tensorflow as tf


def rotate_images(X_imgs):
    X_rotate = []
    tf.reset_default_graph()
    X = tf.placeholder(tf.float32, shape = (n, n, 1))
    k = tf.placeholder(tf.int32)
    tf_img = tf.image.rot90(X, k = k)
    with tf.Session() as sess:
        sess.run(tf.global_variables_initializer())
        for img in X_imgs:
            for i in range(3):  # Rotation at 90, 180 and 270 degrees
                rotated_img = sess.run(tf_img, feed_dict = {X: img, k: i + 1})
                X_rotate.append(rotated_img)

    X_rotate = np.array(X_rotate, dtype = np.float32)
    return X_rotate




当我尝试拟合我的模型时,我收到以下错误消息

InvalidArgumentError: Tensor dense_7_target:0, specified in either feed_devices or fetch_devices was not found in the Graph

看起来graph是tensorflow使用的东西,我认为我在keras和tansorflow之间的交互很糟糕;令人惊讶的是我曾经能够运行我的模型,但现在它又坏了..

如果您需要更多信息,请告诉我;感谢帮助

标签: pythontensorflowkerasneural-network

解决方案


不要使用tf.reset_default_graph(),您可以为您的函数创建一个新的临时图表:

import tensorflow as tf

def rotate_images(X_imgs):
    X_rotate = []
    with tf.Graph().as_default():
        X = tf.placeholder(tf.float32, shape = (n, n, 1))
        k = tf.placeholder(tf.int32)
        tf_img = tf.image.rot90(X, k = k)
        with tf.Session() as sess:
            sess.run(tf.global_variables_initializer())
            for img in X_imgs:
                for i in range(3):  # Rotation at 90, 180 and 270 degrees
                    rotated_img = sess.run(tf_img, feed_dict = {X: img, k: i + 1})
                    X_rotate.append(rotated_img)
        X_rotate = np.array(X_rotate, dtype = np.float32)
        return X_rotate

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