Face Generation

In this project, you'll use generative adversarial networks to generate new images of faces.

Get the Data

You'll be using two datasets in this project:

  • MNIST
  • CelebA

Since the celebA dataset is complex and you're doing GANs in a project for the first time, we want you to test your neural network on MNIST before CelebA. Running the GANs on MNIST will allow you to see how well your model trains sooner.

If you're using FloydHub, set data_dir to "/input" and use the FloydHub data ID "R5KrjnANiKVhLWAkpXhNBe".


In [34]:
data_dir = './data'

# FloydHub - Use with data ID "R5KrjnANiKVhLWAkpXhNBe"
#data_dir = '/input'


"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
import helper

helper.download_extract('mnist', data_dir)
helper.download_extract('celeba', data_dir)


Found mnist Data
Found celeba Data

Explore the Data

MNIST

As you're aware, the MNIST dataset contains images of handwritten digits. You can view the first number of examples by changing show_n_images.


In [2]:
show_n_images = 25

"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
%matplotlib inline
import os
from glob import glob
from matplotlib import pyplot

mnist_images = helper.get_batch(glob(os.path.join(data_dir, 'mnist/*.jpg'))[:show_n_images], 28, 28, 'L')
pyplot.imshow(helper.images_square_grid(mnist_images, 'L'), cmap='gray')


Out[2]:
<matplotlib.image.AxesImage at 0x7f78651a7320>

CelebA

The CelebFaces Attributes Dataset (CelebA) dataset contains over 200,000 celebrity images with annotations. Since you're going to be generating faces, you won't need the annotations. You can view the first number of examples by changing show_n_images.


In [3]:
show_n_images = 50

"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
mnist_images = helper.get_batch(glob(os.path.join(data_dir, 'img_align_celeba/*.jpg'))[:show_n_images], 28, 28, 'RGB')
pyplot.imshow(helper.images_square_grid(mnist_images, 'RGB'))


Out[3]:
<matplotlib.image.AxesImage at 0x7f78650cedd8>

Preprocess the Data

Since the project's main focus is on building the GANs, we'll preprocess the data for you. The values of the MNIST and CelebA dataset will be in the range of -0.5 to 0.5 of 28x28 dimensional images. The CelebA images will be cropped to remove parts of the image that don't include a face, then resized down to 28x28.

The MNIST images are black and white images with a single color channel while the CelebA images have 3 color channels (RGB color channel).

Build the Neural Network

You'll build the components necessary to build a GANs by implementing the following functions below:

  • model_inputs
  • discriminator
  • generator
  • model_loss
  • model_opt
  • train

Check the Version of TensorFlow and Access to GPU

This will check to make sure you have the correct version of TensorFlow and access to a GPU


In [35]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
from distutils.version import LooseVersion
import warnings
import tensorflow as tf

# Check TensorFlow Version
assert LooseVersion(tf.__version__) >= LooseVersion('1.0'), 'Please use TensorFlow version 1.0 or newer.  You are using {}'.format(tf.__version__)
print('TensorFlow Version: {}'.format(tf.__version__))

# Check for a GPU
if not tf.test.gpu_device_name():
    warnings.warn('No GPU found. Please use a GPU to train your neural network.')
else:
    print('Default GPU Device: {}'.format(tf.test.gpu_device_name()))


TensorFlow Version: 1.0.0
Default GPU Device: /gpu:0

Input

Implement the model_inputs function to create TF Placeholders for the Neural Network. It should create the following placeholders:

  • Real input images placeholder with rank 4 using image_width, image_height, and image_channels.
  • Z input placeholder with rank 2 using z_dim.
  • Learning rate placeholder with rank 0.

Return the placeholders in the following the tuple (tensor of real input images, tensor of z data)


In [15]:
import problem_unittests as tests

def model_inputs(image_width, image_height, image_channels, z_dim):
    """
    Create the model inputs
    :param image_width: The input image width
    :param image_height: The input image height
    :param image_channels: The number of image channels
    :param z_dim: The dimension of Z
    :return: Tuple of (tensor of real input images, tensor of z data, learning rate)
    """
    # TODO: Implement Function
    input_real = tf.placeholder(tf.float32, (None, image_width,image_height, image_channels), name='input_real')
    input_z = tf.placeholder(tf.float32, (None, z_dim), name='input_z')
    learning_rate = tf.placeholder(tf.float32, name='learning_rate')
    return input_real, input_z, learning_rate


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_model_inputs(model_inputs)


Tests Passed

Discriminator

Implement discriminator to create a discriminator neural network that discriminates on images. This function should be able to reuse the variabes in the neural network. Use tf.variable_scope with a scope name of "discriminator" to allow the variables to be reused. The function should return a tuple of (tensor output of the generator, tensor logits of the generator).


In [16]:
def discriminator(images, reuse=False):
    """
    Create the discriminator network
    :param image: Tensor of input image(s)
    :param reuse: Boolean if the weights should be reused
    :return: Tuple of (tensor output of the discriminator, tensor logits of the discriminator)
    """
    # TODO: Implement Function
    #normalize
    alpha = 0.1
    with tf.variable_scope('discriminator', reuse=reuse):
        #input image is 28x28x num_channels
        x1 = tf.layers.conv2d(images, 64, 4, strides=2, padding='same')
        relu1 = tf.maximum(alpha * x1, x1)
        # 14x14x64
        
        x2 = tf.layers.conv2d(relu1, 128, 4, strides=2, padding='same')
        bn2 = tf.layers.batch_normalization(x2, training=True)
        relu2 = tf.maximum(alpha * bn2, bn2)
        # 7x7x128
        

        flat = tf.reshape(relu2, (-1, 7*7*128))
        logits = tf.layers.dense(flat, 1)
        out = tf.sigmoid(logits)
        
        return out, logits


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_discriminator(discriminator, tf)


Tests Passed

Generator

Implement generator to generate an image using z. This function should be able to reuse the variabes in the neural network. Use tf.variable_scope with a scope name of "generator" to allow the variables to be reused. The function should return the generated 28 x 28 x out_channel_dim images.


In [17]:
def generator(z, out_channel_dim, is_train=True):
    """
    Create the generator network
    :param z: Input z
    :param out_channel_dim: The number of channels in the output image
    :param is_train: Boolean if generator is being used for training
    :return: The tensor output of the generator
    """
    # TODO: Implement Function
    alpha = 0.1
    with tf.variable_scope('generator',reuse=(not is_train)):
        x1 = tf.layers.dense(z, 7*7*256)
        # Reshape it to start the convolutional stack
        x1 = tf.reshape(x1, (-1, 7, 7, 256))
        x1 = tf.layers.batch_normalization(x1, training=is_train)
        x1 = tf.maximum(alpha * x1, x1)
        # 7x7x256 now
        
        x2 = tf.layers.conv2d_transpose(x1, 64, 5, strides=2, padding='same')
        x2 = tf.layers.batch_normalization(x2, training=is_train)
        x2 = tf.maximum(alpha * x2, x2)
        # 14x14x64 now
        
        
        # Output layer
        logits = tf.layers.conv2d_transpose(x2, out_channel_dim, 5, strides=2, padding='same')
        # 28x28x out_channel_dim now
        
        out = tf.tanh(logits)
        
        return out


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_generator(generator, tf)


Tests Passed

Loss

Implement model_loss to build the GANs for training and calculate the loss. The function should return a tuple of (discriminator loss, generator loss). Use the following functions you implemented:

  • discriminator(images, reuse=False)
  • generator(z, out_channel_dim, is_train=True)

In [18]:
def model_loss(input_real, input_z, out_channel_dim):
    """
    Get the loss for the discriminator and generator
    :param input_real: Images from the real dataset
    :param input_z: Z input
    :param out_channel_dim: The number of channels in the output image
    :return: A tuple of (discriminator loss, generator loss)
    """
    g_model = generator(input_z, out_channel_dim)
    
    d_model_real, d_logits_real = discriminator(input_real)
    d_model_fake, d_logits_fake = discriminator(g_model, reuse=True)

    d_loss_real = tf.reduce_mean(
        tf.nn.sigmoid_cross_entropy_with_logits(logits=d_logits_real, labels=tf.ones_like(d_model_real)))
    d_loss_fake = tf.reduce_mean(
        tf.nn.sigmoid_cross_entropy_with_logits(logits=d_logits_fake, labels=tf.zeros_like(d_model_fake)))
    g_loss = tf.reduce_mean(
        tf.nn.sigmoid_cross_entropy_with_logits(logits=d_logits_fake, labels=tf.ones_like(d_model_fake)))

    d_loss = d_loss_real + d_loss_fake
    
    return d_loss, g_loss


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_model_loss(model_loss)


Tests Passed

Optimization

Implement model_opt to create the optimization operations for the GANs. Use tf.trainable_variables to get all the trainable variables. Filter the variables with names that are in the discriminator and generator scope names. The function should return a tuple of (discriminator training operation, generator training operation).


In [19]:
def model_opt(d_loss, g_loss, learning_rate, beta1):
    """
    Get optimization operations
    :param d_loss: Discriminator loss Tensor
    :param g_loss: Generator loss Tensor
    :param learning_rate: Learning Rate Placeholder
    :param beta1: The exponential decay rate for the 1st moment in the optimizer
    :return: A tuple of (discriminator training operation, generator training operation)
    """
    t_vars = tf.trainable_variables()
    d_vars = [var for var in t_vars if var.name.startswith('discriminator')]
    g_vars = [var for var in t_vars if var.name.startswith('generator')]

    # Optimize (necessary adding UPDATE_OPS to update population statistics)
    with tf.control_dependencies(tf.get_collection(tf.GraphKeys.UPDATE_OPS)):
        d_train_opt = tf.train.AdamOptimizer(learning_rate, beta1=beta1).minimize(d_loss, var_list=d_vars)
        g_train_opt = tf.train.AdamOptimizer(learning_rate, beta1=beta1).minimize(g_loss, var_list=g_vars)
    
    return d_train_opt, g_train_opt


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_model_opt(model_opt, tf)


Tests Passed

Neural Network Training

Show Output

Use this function to show the current output of the generator during training. It will help you determine how well the GANs is training.


In [20]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
import numpy as np

def show_generator_output(sess, n_images, input_z, out_channel_dim, image_mode):
    """
    Show example output for the generator
    :param sess: TensorFlow session
    :param n_images: Number of Images to display
    :param input_z: Input Z Tensor
    :param out_channel_dim: The number of channels in the output image
    :param image_mode: The mode to use for images ("RGB" or "L")
    """
    cmap = None if image_mode == 'RGB' else 'gray'
    z_dim = input_z.get_shape().as_list()[-1]
    example_z = np.random.uniform(-1, 1, size=[n_images, z_dim])

    samples = sess.run(
        generator(input_z, out_channel_dim, False),
        feed_dict={input_z: example_z})

    images_grid = helper.images_square_grid(samples, image_mode)
    pyplot.imshow(images_grid, cmap=cmap)
    pyplot.show()

Train

Implement train to build and train the GANs. Use the following functions you implemented:

  • model_inputs(image_width, image_height, image_channels, z_dim)
  • model_loss(input_real, input_z, out_channel_dim)
  • model_opt(d_loss, g_loss, learning_rate, beta1)

Use the show_generator_output to show generator output while you train. Running show_generator_output for every batch will drastically increase training time and increase the size of the notebook. It's recommended to print the generator output every 100 batches.


In [41]:
def train(epoch_count, batch_size, z_dim, learning_rate, beta1, get_batches, data_shape, data_image_mode):
    """
    Train the GAN
    :param epoch_count: Number of epochs
    :param batch_size: Batch Size
    :param z_dim: Z dimension
    :param learning_rate: Learning Rate
    :param beta1: The exponential decay rate for the 1st moment in the optimizer
    :param get_batches: Function to get batches
    :param data_shape: Shape of the data
    :param data_image_mode: The image mode to use for images ("RGB" or "L")
    """
    # TODO: Build Model
    #print("z_dim = ",z_dim)
    print("data_shape = ",data_shape)
    input_real, input_z,learn_rate  = model_inputs(data_shape[1],data_shape[2],data_shape[3], z_dim)
    d_loss, g_loss = model_loss(input_real, input_z, data_shape[3])

    d_opt, g_opt = model_opt(d_loss, g_loss, learning_rate, beta1)
    
    with tf.Session() as sess:
        sess.run(tf.global_variables_initializer())
        steps=0
        for epoch_i in range(epoch_count):
            for batch_images in get_batches(batch_size):
                steps += 1
                batch_images *=2
                #total_steps= len(get_batches(batch_size))
                #print(batch_images)
                # Sample random noise for G
                batch_z = np.random.uniform(-1, 1, size=(batch_size, z_dim))

                # Run optimizers
                _ = sess.run(d_opt, feed_dict={input_z: batch_z, input_real: batch_images, learn_rate:learning_rate})
                _ = sess.run(g_opt, feed_dict={input_z: batch_z, input_real: batch_images, learn_rate:learning_rate})
                
                train_loss_d = sess.run(d_loss, {input_z: batch_z, input_real: batch_images})
                train_loss_g = g_loss.eval({input_z: batch_z})
                if steps % 50 == 0:
                    print("Epoch {}/{}, step {}/{}...".format(epoch_i+1, epoch_count,steps,data_shape[0]/batch_size*(epoch_count)),
                        "Discriminator Loss: {:.4f}...".format(train_loss_d),
                        "Generator Loss: {:.4f}".format(train_loss_g))    

                    show_generator_output(sess, 25, input_z, data_shape[3], data_image_mode)

MNIST

Test your GANs architecture on MNIST. After 2 epochs, the GANs should be able to generate images that look like handwritten digits. Make sure the loss of the generator is lower than the loss of the discriminator or close to 0.


In [42]:
batch_size = 200
z_dim = 100
learning_rate = 0.01
beta1 = 0.2


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
epochs = 2

mnist_dataset = helper.Dataset('mnist', glob(os.path.join(data_dir, 'mnist/*.jpg')))
with tf.Graph().as_default():
    train(epochs, batch_size, z_dim, learning_rate, beta1, mnist_dataset.get_batches,
          mnist_dataset.shape, mnist_dataset.image_mode)


data_shape =  (60000, 28, 28, 1)
Epoch 1/2, step 50/600.0... Discriminator Loss: 2.3854... Generator Loss: 0.1804
Epoch 1/2, step 100/600.0... Discriminator Loss: 1.6465... Generator Loss: 0.3155
Epoch 1/2, step 150/600.0... Discriminator Loss: 1.4960... Generator Loss: 0.3239
Epoch 1/2, step 200/600.0... Discriminator Loss: 1.3922... Generator Loss: 0.4001
Epoch 1/2, step 250/600.0... Discriminator Loss: 1.2504... Generator Loss: 0.7422
Epoch 1/2, step 300/600.0... Discriminator Loss: 1.1530... Generator Loss: 1.2458
Epoch 2/2, step 350/600.0... Discriminator Loss: 1.3238... Generator Loss: 0.9003
Epoch 2/2, step 400/600.0... Discriminator Loss: 1.5135... Generator Loss: 0.3714
Epoch 2/2, step 450/600.0... Discriminator Loss: 1.3147... Generator Loss: 0.7057
Epoch 2/2, step 500/600.0... Discriminator Loss: 1.4148... Generator Loss: 0.4511
Epoch 2/2, step 550/600.0... Discriminator Loss: 1.4161... Generator Loss: 1.0596
Epoch 2/2, step 600/600.0... Discriminator Loss: 1.4508... Generator Loss: 0.4067

CelebA

Run your GANs on CelebA. It will take around 20 minutes on the average GPU to run one epoch. You can run the whole epoch or stop when it starts to generate realistic faces.


In [44]:
batch_size = 200
z_dim = 100
learning_rate = 0.001
beta1 = 0.2


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
epochs = 2

celeba_dataset = helper.Dataset('celeba', glob(os.path.join(data_dir, 'img_align_celeba/*.jpg')))
with tf.Graph().as_default():
    train(epochs, batch_size, z_dim, learning_rate, beta1, celeba_dataset.get_batches,
          celeba_dataset.shape, celeba_dataset.image_mode)


data_shape =  (202599, 28, 28, 3)
Epoch 1/2, step 50/2025.99... Discriminator Loss: 2.1445... Generator Loss: 0.1775
Epoch 1/2, step 100/2025.99... Discriminator Loss: 1.3468... Generator Loss: 0.5233
Epoch 1/2, step 150/2025.99... Discriminator Loss: 0.8666... Generator Loss: 0.7379
Epoch 1/2, step 200/2025.99... Discriminator Loss: 1.6713... Generator Loss: 0.3049
Epoch 1/2, step 250/2025.99... Discriminator Loss: 1.1802... Generator Loss: 0.9720
Epoch 1/2, step 300/2025.99... Discriminator Loss: 1.4770... Generator Loss: 0.5000
Epoch 1/2, step 350/2025.99... Discriminator Loss: 1.3535... Generator Loss: 0.5865
Epoch 1/2, step 400/2025.99... Discriminator Loss: 1.3882... Generator Loss: 0.7833
Epoch 1/2, step 450/2025.99... Discriminator Loss: 0.8176... Generator Loss: 1.2735
Epoch 1/2, step 500/2025.99... Discriminator Loss: 1.3401... Generator Loss: 0.7695
Epoch 1/2, step 550/2025.99... Discriminator Loss: 1.6641... Generator Loss: 0.7974
Epoch 1/2, step 600/2025.99... Discriminator Loss: 1.6118... Generator Loss: 0.3252
Epoch 1/2, step 650/2025.99... Discriminator Loss: 1.1177... Generator Loss: 0.9687
Epoch 1/2, step 700/2025.99... Discriminator Loss: 1.3998... Generator Loss: 0.5791
Epoch 1/2, step 750/2025.99... Discriminator Loss: 0.9394... Generator Loss: 0.9359
Epoch 1/2, step 800/2025.99... Discriminator Loss: 1.4200... Generator Loss: 0.5917
Epoch 1/2, step 850/2025.99... Discriminator Loss: 0.8712... Generator Loss: 1.6035
Epoch 1/2, step 900/2025.99... Discriminator Loss: 1.0669... Generator Loss: 1.6695
Epoch 1/2, step 950/2025.99... Discriminator Loss: 0.9622... Generator Loss: 1.0970
Epoch 1/2, step 1000/2025.99... Discriminator Loss: 1.3993... Generator Loss: 0.5434
Epoch 2/2, step 1050/2025.99... Discriminator Loss: 1.5673... Generator Loss: 0.4049
Epoch 2/2, step 1100/2025.99... Discriminator Loss: 1.4282... Generator Loss: 0.7001
Epoch 2/2, step 1150/2025.99... Discriminator Loss: 1.2463... Generator Loss: 0.7820
Epoch 2/2, step 1200/2025.99... Discriminator Loss: 1.3622... Generator Loss: 0.7943
Epoch 2/2, step 1250/2025.99... Discriminator Loss: 1.2241... Generator Loss: 0.8063
Epoch 2/2, step 1300/2025.99... Discriminator Loss: 1.3567... Generator Loss: 0.8019
Epoch 2/2, step 1350/2025.99... Discriminator Loss: 1.4213... Generator Loss: 0.8460
Epoch 2/2, step 1400/2025.99... Discriminator Loss: 1.6394... Generator Loss: 0.4086
Epoch 2/2, step 1450/2025.99... Discriminator Loss: 1.2448... Generator Loss: 0.8387
Epoch 2/2, step 1500/2025.99... Discriminator Loss: 1.4903... Generator Loss: 0.7001
Epoch 2/2, step 1550/2025.99... Discriminator Loss: 1.3843... Generator Loss: 0.5592
Epoch 2/2, step 1600/2025.99... Discriminator Loss: 1.2213... Generator Loss: 0.8210
Epoch 2/2, step 1650/2025.99... Discriminator Loss: 1.4290... Generator Loss: 0.8330
Epoch 2/2, step 1700/2025.99... Discriminator Loss: 1.4586... Generator Loss: 0.4093
Epoch 2/2, step 1750/2025.99... Discriminator Loss: 1.3392... Generator Loss: 0.7890
Epoch 2/2, step 1800/2025.99... Discriminator Loss: 2.1623... Generator Loss: 1.0983
Epoch 2/2, step 1850/2025.99... Discriminator Loss: 1.3932... Generator Loss: 0.6268
Epoch 2/2, step 1900/2025.99... Discriminator Loss: 1.3997... Generator Loss: 0.5664
Epoch 2/2, step 1950/2025.99... Discriminator Loss: 1.3687... Generator Loss: 0.6293
Epoch 2/2, step 2000/2025.99... Discriminator Loss: 1.4038... Generator Loss: 0.4801

Submitting This Project

When submitting this project, make sure to run all the cells before saving the notebook. Save the notebook file as "dlnd_face_generation.ipynb" and save it as a HTML file under "File" -> "Download as". Include the "helper.py" and "problem_unittests.py" files in your submission.