Pixel2Pixel

朱雀 2023-07-02 05:23 47阅读 0赞

# ![20191009191333910.png][] #

# [日萌社][Link 1] #

[人工智能AI：Keras PyTorch MXNet TensorFlow PaddlePaddle 深度学习实战（不定时更新）][AI_Keras PyTorch MXNet TensorFlow PaddlePaddle]

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# ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9henVzYS5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70][] #

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# **gd.py ** #

import  os
    import  tensorflow as tf
    import  numpy as np
    from    tensorflow import keras
    
    
    
    
    class Downsample(keras.Model):
    
        def __init__(self, filters, size, apply_batchnorm=True):
            super(Downsample, self).__init__()
            
            self.apply_batchnorm = apply_batchnorm
            initializer = tf.random_normal_initializer(0., 0.02)
    
            self.conv1 = keras.layers.Conv2D(filters,
                                                (size, size),
                                                strides=2,
                                                padding='same',
                                                kernel_initializer=initializer,
                                                use_bias=False)
            if self.apply_batchnorm:
                self.batchnorm = keras.layers.BatchNormalization()
    
        def call(self, x, training):
            x = self.conv1(x)
            if self.apply_batchnorm:
                x = self.batchnorm(x, training=training)
            x = tf.nn.leaky_relu(x)
            return x
    
    
    class Upsample(keras.Model):
    
        def __init__(self, filters, size, apply_dropout=False):
            super(Upsample, self).__init__()
            
            self.apply_dropout = apply_dropout
            initializer = tf.random_normal_initializer(0., 0.02)
    
            self.up_conv = keras.layers.Conv2DTranspose(filters,
                                                           (size, size),
                                                           strides=2,
                                                           padding='same',
                                                           kernel_initializer=initializer,
                                                           use_bias=False)
            self.batchnorm = keras.layers.BatchNormalization()
            if self.apply_dropout:
                self.dropout = keras.layers.Dropout(0.5)
    
        def call(self, x1, x2, training=None):
    
            x = self.up_conv(x1)
            x = self.batchnorm(x, training=training)
            if self.apply_dropout:
                x = self.dropout(x, training=training)
            x = tf.nn.relu(x)
            x = tf.concat([x, x2], axis=-1)
            return x
    
    
    class Generator(keras.Model):
    
        def __init__(self):
            super(Generator, self).__init__()
    
            initializer = tf.random_normal_initializer(0., 0.02)
    
            self.down1 = Downsample(64, 4, apply_batchnorm=False)
            self.down2 = Downsample(128, 4)
            self.down3 = Downsample(256, 4)
            self.down4 = Downsample(512, 4)
            self.down5 = Downsample(512, 4)
            self.down6 = Downsample(512, 4)
            self.down7 = Downsample(512, 4)
            self.down8 = Downsample(512, 4)
    
            self.up1 = Upsample(512, 4, apply_dropout=True)
            self.up2 = Upsample(512, 4, apply_dropout=True)
            self.up3 = Upsample(512, 4, apply_dropout=True)
            self.up4 = Upsample(512, 4)
            self.up5 = Upsample(256, 4)
            self.up6 = Upsample(128, 4)
            self.up7 = Upsample(64, 4)
    
            self.last = keras.layers.Conv2DTranspose(3, (4, 4),
                                                        strides=2,
                                                        padding='same',
                                                        kernel_initializer=initializer)
    
    
        def call(self, x, training=None):
    
            # x shape == (bs, 256, 256, 3)    
            x1 = self.down1(x, training=training)  # (bs, 128, 128, 64)
            x2 = self.down2(x1, training=training)  # (bs, 64, 64, 128)
            x3 = self.down3(x2, training=training)  # (bs, 32, 32, 256)
            x4 = self.down4(x3, training=training)  # (bs, 16, 16, 512)
            x5 = self.down5(x4, training=training)  # (bs, 8, 8, 512)
            x6 = self.down6(x5, training=training)  # (bs, 4, 4, 512)
            x7 = self.down7(x6, training=training)  # (bs, 2, 2, 512)
            x8 = self.down8(x7, training=training)  # (bs, 1, 1, 512)
    
            x9 = self.up1(x8, x7, training=training)  # (bs, 2, 2, 1024)
            x10 = self.up2(x9, x6, training=training)  # (bs, 4, 4, 1024)
            x11 = self.up3(x10, x5, training=training)  # (bs, 8, 8, 1024)
            x12 = self.up4(x11, x4, training=training)  # (bs, 16, 16, 1024)
            x13 = self.up5(x12, x3, training=training)  # (bs, 32, 32, 512)
            x14 = self.up6(x13, x2, training=training)  # (bs, 64, 64, 256)
            x15 = self.up7(x14, x1, training=training)  # (bs, 128, 128, 128)
    
            x16 = self.last(x15)  # (bs, 256, 256, 3)
            x16 = tf.nn.tanh(x16)
    
            return x16
    
    
    class DiscDownsample(keras.Model):
    
        def __init__(self, filters, size, apply_batchnorm=True):
            super(DiscDownsample, self).__init__()
    
            self.apply_batchnorm = apply_batchnorm
            initializer = tf.random_normal_initializer(0., 0.02)
    
            self.conv1 = keras.layers.Conv2D(filters, (size, size),
                                                strides=2,
                                                padding='same',
                                                kernel_initializer=initializer,
                                                use_bias=False)
            if self.apply_batchnorm:
                self.batchnorm = keras.layers.BatchNormalization()
    
        def call(self, x, training=None):
    
            x = self.conv1(x)
            if self.apply_batchnorm:
                x = self.batchnorm(x, training=training)
            x = tf.nn.leaky_relu(x)
            return x
    
    
    class Discriminator(keras.Model):
    
        def __init__(self):
            super(Discriminator, self).__init__()
    
            initializer = tf.random_normal_initializer(0., 0.02)
    
            self.down1 = DiscDownsample(64, 4, False)
            self.down2 = DiscDownsample(128, 4)
            self.down3 = DiscDownsample(256, 4)
    
            # we are zero padding here with 1 because we need our shape to 
            # go from (batch_size, 32, 32, 256) to (batch_size, 31, 31, 512)
            self.zero_pad1 = keras.layers.ZeroPadding2D()
            self.conv = keras.layers.Conv2D(512, (4, 4),
                                               strides=1,
                                               kernel_initializer=initializer,
                                               use_bias=False)
            self.batchnorm1 = keras.layers.BatchNormalization()
    
            # shape change from (batch_size, 31, 31, 512) to (batch_size, 30, 30, 1)
            self.zero_pad2 = keras.layers.ZeroPadding2D()
            self.last = keras.layers.Conv2D(1, (4, 4),
                                               strides=1,
                                               kernel_initializer=initializer)
    
    
        def call(self, inputs, training=None):
            inp, target = inputs
    
            # concatenating the input and the target
            x = tf.concat([inp, target], axis=-1)  # (bs, 256, 256, channels*2)
            x = self.down1(x, training=training)  # (bs, 128, 128, 64)
            x = self.down2(x, training=training)  # (bs, 64, 64, 128)
            x = self.down3(x, training=training)  # (bs, 32, 32, 256)
    
            x = self.zero_pad1(x)  # (bs, 34, 34, 256)
            x = self.conv(x)  # (bs, 31, 31, 512)
            x = self.batchnorm1(x, training=training)
            x = tf.nn.leaky_relu(x)
    
            x = self.zero_pad2(x)  # (bs, 33, 33, 512)
            # don't add a sigmoid activation here since
            # the loss function expects raw logits.
            x = self.last(x)  # (bs, 30, 30, 1)
    
            return x

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# **main.py** #

import  os
    import  tensorflow as tf
    import  numpy as np
    from    tensorflow import keras
    import  time
    from    matplotlib import pyplot as plt
    
    from    gd import Discriminator, Generator
    
    tf.random.set_seed(22)
    np.random.seed(22)
    os.environ['TF_CPP_MIN_LOG_LEVEL'] = '2'
    assert tf.__version__.startswith('2.')
    
    
    batch_size = 1
    IMG_WIDTH = 256
    IMG_HEIGHT = 256
    
    
    path_to_zip = keras.utils.get_file('facades.tar.gz',
                                      cache_subdir=os.path.abspath('.'),
                                      origin='https://people.eecs.berkeley.edu/~tinghuiz/projects/pix2pix/datasets/facades.tar.gz',
                                      extract=True)
    
    PATH = os.path.join(os.path.dirname(path_to_zip), 'facades/')
    print('dataset path:', PATH)
    
    def load_image(image_file, is_train):
        """
        load and preprocess images
        :param image_file:
        :param is_train:
        :return:
        """
        image = tf.io.read_file(image_file)
        image = tf.image.decode_jpeg(image)
    
        w = image.shape[1]
    
        w = w // 2
        real_image = image[:, :w, :]
        input_image = image[:, w:, :]
    
        input_image = tf.cast(input_image, tf.float32)
        real_image = tf.cast(real_image, tf.float32)
    
        if is_train:
            # random jittering
    
            # resizing to 286 x 286 x 3
            input_image = tf.image.resize(input_image, [286, 286])
            real_image = tf.image.resize(real_image, [286, 286])
    
            # randomly cropping to 256 x 256 x 3
            stacked_image = tf.stack([input_image, real_image], axis=0)
            cropped_image = tf.image.random_crop(stacked_image, size=[2, IMG_HEIGHT, IMG_WIDTH, 3])
            input_image, real_image = cropped_image[0], cropped_image[1]
    
            if np.random.random() > 0.5:
                # random mirroring
                input_image = tf.image.flip_left_right(input_image)
                real_image = tf.image.flip_left_right(real_image)
        else:
            input_image = tf.image.resize(input_image, size=[IMG_HEIGHT, IMG_WIDTH])
            real_image = tf.image.resize(real_image, size=[IMG_HEIGHT, IMG_WIDTH])
    
        # normalizing the images to [-1, 1]
        input_image = (input_image / 127.5) - 1
        real_image = (real_image / 127.5) - 1
    
        # [256, 256, 3], [256, 256, 3]
        # print(input_image.shape, real_image.shape)
    
        # => [256, 256, 6]
        out = tf.concat([input_image, real_image], axis=2)
    
        return out
    
    
    
    
    
    train_dataset = tf.data.Dataset.list_files(PATH+'/train/*.jpg')
    # The following snippet can not work, so load it hand by hand.
    # train_dataset = train_dataset.map(lambda x: load_image(x, True)).batch(1)
    train_iter = iter(train_dataset)
    train_data = []
    for x in train_iter:
        train_data.append(load_image(x, True))
    train_data = tf.stack(train_data, axis=0)
    # [800, 256, 256, 3]
    print('train:', train_data.shape)
    train_dataset = tf.data.Dataset.from_tensor_slices(train_data)
    train_dataset = train_dataset.shuffle(400).batch(1)
    
    test_dataset = tf.data.Dataset.list_files(PATH+'test/*.jpg')
    # test_dataset = test_dataset.map(lambda x: load_image(x, False)).batch(1)
    test_iter = iter(test_dataset)
    test_data = []
    for x in test_iter:
        test_data.append(load_image(x, False))
    test_data = tf.stack(test_data, axis=0)
    # [800, 256, 256, 3]
    print('test:', test_data.shape)
    test_dataset = tf.data.Dataset.from_tensor_slices(test_data)
    test_dataset = test_dataset.shuffle(400).batch(1)
    
    generator = Generator()
    generator.build(input_shape=(batch_size, 256, 256, 3))
    generator.summary()
    discriminator = Discriminator()
    discriminator.build(input_shape=[(batch_size, 256, 256, 3), (batch_size, 256, 256, 3)])
    discriminator.summary()
    
    g_optimizer = keras.optimizers.Adam(learning_rate=2e-4, beta_1=0.5)
    d_optimizer = keras.optimizers.Adam(learning_rate=2e-4, beta_1=0.5)
    
    
    
    
    def discriminator_loss(disc_real_output, disc_generated_output):
        # [1, 30, 30, 1] with [1, 30, 30, 1]
        # print(disc_real_output.shape, disc_generated_output.shape)
        real_loss = keras.losses.binary_crossentropy(
                        tf.ones_like(disc_real_output), disc_real_output, from_logits=True)
    
        generated_loss = keras.losses.binary_crossentropy(
                        tf.zeros_like(disc_generated_output), disc_generated_output, from_logits=True)
    
        real_loss = tf.reduce_mean(real_loss)
        generated_loss = tf.reduce_mean(generated_loss)
    
        total_disc_loss = real_loss + generated_loss
    
        return total_disc_loss
    
    
    
    def generator_loss(disc_generated_output, gen_output, target):
    
        LAMBDA = 100
    
        gan_loss = keras.losses.binary_crossentropy(
                    tf.ones_like(disc_generated_output), disc_generated_output, from_logits=True)
        # mean absolute error
        l1_loss = tf.reduce_mean(tf.abs(target - gen_output))
    
        gan_loss = tf.reduce_mean(gan_loss)
    
        total_gen_loss = gan_loss + (LAMBDA * l1_loss)
    
        return total_gen_loss
    
    
    
    def generate_images(model, test_input, tar, epoch):
        # the training=True is intentional here since
        # we want the batch statistics while running the model
        # on the test dataset. If we use training=False, we will get
        # the accumulated statistics learned from the training dataset
        # (which we don't want)
        prediction = model(test_input, training=True)
        plt.figure(figsize=(15,15))
    
        display_list = [test_input[0], tar[0], prediction[0]]
        title = ['Input Image', 'Ground Truth', 'Predicted Image']
    
        for i in range(3):
            plt.subplot(1, 3, i+1)
            plt.title(title[i])
            # getting the pixel values between [0, 1] to plot it.
            plt.imshow(display_list[i] * 0.5 + 0.5)
            plt.axis('off')
        plt.savefig('images/epoch%d.png'%epoch)
        print('saved images.')
        # plt.show()
    
    
    
    
    
    
    
    
    def main():
    
        epochs = 1000
    
        for epoch in range(epochs):
    
            start = time.time()
    
            for step, inputs in enumerate(train_dataset):
    
                input_image, target = tf.split(inputs, num_or_size_splits=[3, 3], axis=3)
                # print(input_image.shape, target.shape)
    
                with tf.GradientTape() as gen_tape, tf.GradientTape() as disc_tape:
                    # get generated pixel2pixel image
                    gen_output = generator(input_image, training=True)
                    # fed real pixel2pixel image together with original image
                    disc_real_output = discriminator([input_image, target], training=True)
                    # fed generated/fake pixel2pixel image together with original image
                    disc_generated_output = discriminator([input_image, gen_output], training=True)
    
                    gen_loss = generator_loss(disc_generated_output, gen_output, target)
                    disc_loss = discriminator_loss(disc_real_output, disc_generated_output)
    
                generator_gradients = gen_tape.gradient(gen_loss, generator.trainable_variables)
                g_optimizer.apply_gradients(zip(generator_gradients, generator.trainable_variables))
    
                discriminator_gradients = disc_tape.gradient(disc_loss, discriminator.trainable_variables)
                d_optimizer.apply_gradients(zip(discriminator_gradients, discriminator.trainable_variables))
    
                if step% 100 == 0:
                    # print(disc_loss.shape, gen_loss.shape)
                    print(epoch, step, float(disc_loss), float(gen_loss))
    
            if epoch % 1 == 0:
    
                for inputs in test_dataset:
                    input_image, target = tf.split(inputs, num_or_size_splits=[3, 3], axis=3)
                    generate_images(generator, input_image, target, epoch)
                    break
    
            print('Time taken for epoch {} is {} sec\n'.format(epoch + 1, time.time() - start))
    
    
    
        for inputs in test_dataset:
            input_image, target = tf.split(inputs, num_or_size_splits=[3, 3], axis=3)
            generate_images(generator, input_image, target, 99999)
            break
    
    
    
    
    
    if __name__ == '__main__':
        main()

[20191009191333910.png]: https://img-blog.csdnimg.cn/20191009191333910.png
[Link 1]: http://www.rimengshe.com/
[AI_Keras PyTorch MXNet TensorFlow PaddlePaddle]: https://blog.csdn.net/zimiao552147572/article/details/88867161
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9henVzYS5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200126181117822.jpg?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9henVzYS5ibG9nLmNzZG4ubmV0,size_16,color_FFFFFF,t_70