Exemple #1
0
def webcam(style_transform_path, width=1280, height=720):
    """
    Captures and saves an image, perform style transfer, and again saves the styled image.
    Reads the styled image and show in window. 

    Saving and loading SHOULD BE eliminated, however this produces too much whitening in
    the "generated styled image". This may be caused by the async nature of VideoCapture,
    and I don't know how to fix it. 
    """
    # Device
    device = ("cuda" if torch.cuda.is_available() else "cpu")

    # Load Transformer Network
    print("Loading Transformer Network")
    net = transformer.TransformerNetwork()
    net.load_state_dict(torch.load(style_transform_path))
    net = net.to(device)
    print("Done Loading Transformer Network")

    # Set webcam settings
    cam = cv2.VideoCapture(0)
    cam.set(3, width)
    cam.set(4, height)

    # Main loop
    with torch.no_grad():
        count = 1
        while True:
            # Get webcam input
            ret_val, img = cam.read()

            # Mirror
            img = cv2.flip(img, 1)
            utils.saveimg(img, str(count) + ".png")

            # Free-up unneeded cuda memory
            torch.cuda.empty_cache()

            # Generate image
            content_image = utils.load_image(str(count) + ".png")
            content_tensor = utils.itot(content_image).to(device)
            generated_tensor = net(content_tensor)
            generated_image = utils.ttoi(generated_tensor.detach())
            if (PRESERVE_COLOR):
                generated_image = utils.transfer_color(content_image,
                                                       generated_image)
            utils.saveimg(generated_image, str(count + 1) + ".png")
            img2 = cv2.imread(str(count + 1) + ".png")

            count += 2
            # Show webcam
            cv2.imshow('Demo webcam', img2)
            if cv2.waitKey(1) == 27:
                break  # esc to quit

    # Free-up memories
    cam.release()
    cv2.destroyAllWindows()
Exemple #2
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def stylize_folder(style_path, folder_containing_the_content_folder, save_folder, batch_size=1):
    """Stylizes images in a folder by batch
    If the images  are of different dimensions, use transform.resize() or use a batch size of 1
    IMPORTANT: Put content_folder inside another folder folder_containing_the_content_folder

    folder_containing_the_content_folder
        content_folder
            pic1.ext
            pic2.ext
            pic3.ext
            ...

    and saves as the styled images in save_folder as follow:

    save_folder
        pic1.ext
        pic2.ext
        pic3.ext
        ...
    """
    # Device
    device = ("cuda" if torch.cuda.is_available() else "cpu")

    # Image loader
    transform = transforms.Compose([
        transforms.ToTensor(),
        transforms.Lambda(lambda x: x.mul(255))
    ])
    image_dataset = utils.ImageFolderWithPaths(folder_containing_the_content_folder, transform=transform)
    image_loader = torch.utils.data.DataLoader(image_dataset, batch_size=batch_size)

    # Load Transformer Network
    net = transformer.TransformerNetwork()
    net.load_state_dict(torch.load(style_path))
    net = net.to(device)

    # Stylize batches of images
    with torch.no_grad():
        for content_batch, _, path in image_loader:
            # Free-up unneeded cuda memory
            torch.cuda.empty_cache()

            # Generate image
            generated_tensor = net(content_batch.to(device)).detach()

            # Save images
            for i in range(len(path)):
                generated_image = utils.ttoi(generated_tensor[i])
                if (PRESERVE_COLOR):
                    generated_image = utils.transfer_color(content_image, generated_image)
                image_name = os.path.basename(path[i])
                utils.saveimg(generated_image, save_folder + image_name)

#stylize()
def webcam(style_transform_path, width=1280, height=720):
    """
    Captures and saves an image, perform style transfer, and again saves the styled image.
    Reads the styled image and show in window. 
    """
    # Device
    device = "cuda" if torch.cuda.is_available() else "cpu"

    # Load Transformer Network
    print("Loading Transformer Network")
    net = transformer.TransformerNetwork()
    net.load_state_dict(torch.load(style_transform_path))
    net = net.to(device)
    print("Done Loading Transformer Network")

    # Set webcam settings
    cam = cv2.VideoCapture(0)
    cam.set(3, width)
    cam.set(4, height)

    # Main loop
    with torch.no_grad():
        while True:
            # Get webcam input
            ret_val, img = cam.read()

            # Mirror
            img = cv2.flip(img, 1)

            # Free-up unneeded cuda memory
            torch.cuda.empty_cache()

            # Generate image
            content_tensor = utils.itot(img).to(device)
            generated_tensor = net(content_tensor)
            generated_image = utils.ttoi(generated_tensor.detach())
            if PRESERVE_COLOR:
                generated_image = utils.transfer_color(img, generated_image)

            generated_image = generated_image / 255

            # Show webcam
            cv2.imshow("Demo webcam", generated_image)
            if cv2.waitKey(1) == 27:
                break  # esc to quit

    # Free-up memories
    cam.release()
    cv2.destroyAllWindows()
Exemple #4
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def webcam(style_transform_path, width=1280, height=720):
    # Device
    device = ("cuda" if torch.cuda.is_available() else "cpu")

    # Load Transformer Network
    print("Loading Transformer Network")
    net = transformer.TransformerNetwork()
    net.load_state_dict(torch.load(style_transform_path, map_location=device))
    net = net.to(device)
    print("Done Loading Transformer Network")

    # Set webcam settings
    cam = cv2.VideoCapture(0)
    cam.set(3, width)
    cam.set(4, height)

    # Main loop
    with torch.no_grad():
        count = 1
        while True:
            # Get webcam input
            ret_val, img = cam.read()

            # AI Mirror
            img = cv2.flip(img, 1)

            # Free-up unneeded cuda memory
            torch.cuda.empty_cache()

            # Generate image
            content_tensor = utils.itot(img).to(device)
            generated_tensor = net(content_tensor)
            generated_image = utils.ttoi(generated_tensor.detach())
            if (PRESERVE_COLOR):
                generated_image = utils.transfer_color(content_image,
                                                       generated_image)
            img2 = cv2.imdecode(
                cv2.imencode(".png", generated_image)[1], cv2.IMREAD_UNCHANGED)

            count += 2
            # Show webcam
            cv2.imshow('Demo webcam', img2)
            if cv2.waitKey(1) == 27:
                break  # esc to quit

    # Free-up memories
    cam.release()
    cv2.destroyAllWindows()
Exemple #5
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def stylize_folder_single(style_path, content_folder, save_folder):
    """
    Reads frames/pictures as follows:

    content_folder
        pic1.ext
        pic2.ext
        pic3.ext
        ...

    and saves as the styled images in save_folder as follow:

    save_folder
        pic1.ext
        pic2.ext
        pic3.ext
        ...
    """
    # Device
    device = ("cuda" if torch.cuda.is_available() else "cpu")

    # Load Transformer Network
    net = transformer.TransformerNetwork()
    net.load_state_dict(torch.load(style_path))
    net = net.to(device)

    # Stylize every frame
    images = [img for img in os.listdir(content_folder) if img.endswith(".jpg")]
    with torch.no_grad():
        for image_name in images:
            # Free-up unneeded cuda memory
            torch.cuda.empty_cache()
            
            # Load content image
            content_image = utils.load_image(content_folder + image_name)
            content_tensor = utils.itot(content_image).to(device)

            # Generate image
            generated_tensor = net(content_tensor)
            generated_image = utils.ttoi(generated_tensor.detach())
            if (PRESERVE_COLOR):
                generated_image = utils.transfer_color(content_image, generated_image)
            # Save image
            utils.saveimg(generated_image, save_folder + image_name)
Exemple #6
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def stylize():
    # Device
    device = ("cuda" if torch.cuda.is_available() else "cpu")

    # Load Transformer Network
    net = transformer.TransformerNetwork()
    net.load_state_dict(torch.load(STYLE_TRANSFORM_PATH))
    net = net.to(device)

    with torch.no_grad():
        while(1):
            torch.cuda.empty_cache()
            print("Stylize Image~ Press Ctrl+C and Enter to close the program")
            content_image_path = input("Enter the image path: ")
            content_image = utils.load_image(content_image_path)
            starttime = time.time()
            content_tensor = utils.itot(content_image).to(device)
            generated_tensor = net(content_tensor)
            generated_image = utils.ttoi(generated_tensor.detach())
            if (PRESERVE_COLOR):
                generated_image = utils.transfer_color(content_image, generated_image)
            print("Transfer Time: {}".format(time.time() - starttime))
            utils.show(generated_image)
            utils.saveimg(generated_image, "helloworld.jpg")
Exemple #7
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def train():
    # Seeds
    torch.manual_seed(SEED)
    torch.cuda.manual_seed(SEED)
    np.random.seed(SEED)
    random.seed(SEED)

    # Device
    device = "cuda" if torch.cuda.is_available() else "cpu"

    # Dataset and Dataloader
    transform = transforms.Compose([
        transforms.Resize(TRAIN_IMAGE_SIZE),
        transforms.CenterCrop(TRAIN_IMAGE_SIZE),
        transforms.ToTensor(),
        transforms.Lambda(lambda x: x.mul(255)),
    ])
    train_dataset = datasets.ImageFolder(DATASET_PATH, transform=transform)
    train_loader = torch.utils.data.DataLoader(train_dataset,
                                               batch_size=BATCH_SIZE,
                                               shuffle=True)

    # Load networks
    TransformerNetwork = transformer.TransformerNetwork().to(device)
    VGG = vgg.VGG16().to(device)

    # Get Style Features
    imagenet_neg_mean = (torch.tensor([-103.939, -116.779, -123.68],
                                      dtype=torch.float32).reshape(
                                          1, 3, 1, 1).to(device))
    style_image = utils.load_image(STYLE_IMAGE_PATH)
    style_tensor = utils.itot(style_image).to(device)
    style_tensor = style_tensor.add(imagenet_neg_mean)
    B, C, H, W = style_tensor.shape
    style_features = VGG(style_tensor.expand([BATCH_SIZE, C, H, W]))
    style_gram = {}
    for key, value in style_features.items():
        style_gram[key] = utils.gram(value)

    # Optimizer settings
    optimizer = optim.Adam(TransformerNetwork.parameters(), lr=ADAM_LR)

    # Loss trackers
    content_loss_history = []
    style_loss_history = []
    total_loss_history = []
    batch_content_loss_sum = 0
    batch_style_loss_sum = 0
    batch_total_loss_sum = 0

    # Optimization/Training Loop
    batch_count = 1
    start_time = time.time()
    for epoch in range(NUM_EPOCHS):
        print("========Epoch {}/{}========".format(epoch + 1, NUM_EPOCHS))
        for content_batch, _ in train_loader:
            # Get current batch size in case of odd batch sizes
            curr_batch_size = content_batch.shape[0]

            # Free-up unneeded cuda memory
            torch.cuda.empty_cache()

            # Zero-out Gradients
            optimizer.zero_grad()

            # Generate images and get features
            content_batch = content_batch[:, [2, 1, 0]].to(device)
            generated_batch = TransformerNetwork(content_batch)
            content_features = VGG(content_batch.add(imagenet_neg_mean))
            generated_features = VGG(generated_batch.add(imagenet_neg_mean))

            # Content Loss
            MSELoss = nn.MSELoss().to(device)
            content_loss = CONTENT_WEIGHT * MSELoss(
                generated_features["relu2_2"], content_features["relu2_2"])
            batch_content_loss_sum += content_loss

            # Style Loss
            style_loss = 0
            for key, value in generated_features.items():
                s_loss = MSELoss(utils.gram(value),
                                 style_gram[key][:curr_batch_size])
                style_loss += s_loss
            style_loss *= STYLE_WEIGHT
            batch_style_loss_sum += style_loss.item()

            # Total Loss
            total_loss = content_loss + style_loss
            batch_total_loss_sum += total_loss.item()

            # Backprop and Weight Update
            total_loss.backward()
            optimizer.step()

            # Save Model and Print Losses
            if ((batch_count - 1) % SAVE_MODEL_EVERY
                    == 0) or (batch_count == NUM_EPOCHS * len(train_loader)):
                # Print Losses
                print("========Iteration {}/{}========".format(
                    batch_count, NUM_EPOCHS * len(train_loader)))
                print("\tContent Loss:\t{:.2f}".format(batch_content_loss_sum /
                                                       batch_count))
                print("\tStyle Loss:\t{:.2f}".format(batch_style_loss_sum /
                                                     batch_count))
                print("\tTotal Loss:\t{:.2f}".format(batch_total_loss_sum /
                                                     batch_count))
                print("Time elapsed:\t{} seconds".format(time.time() -
                                                         start_time))

                # Save Model
                checkpoint_path = (SAVE_MODEL_PATH + "checkpoint_" +
                                   str(batch_count - 1) + ".pth")
                torch.save(TransformerNetwork.state_dict(), checkpoint_path)
                print("Saved TransformerNetwork checkpoint file at {}".format(
                    checkpoint_path))

                # Save sample generated image
                sample_tensor = generated_batch[0].clone().detach().unsqueeze(
                    dim=0)
                sample_image = utils.ttoi(sample_tensor.clone().detach())
                sample_image_path = (SAVE_IMAGE_PATH + "sample0_" +
                                     str(batch_count - 1) + ".png")
                utils.saveimg(sample_image, sample_image_path)
                print("Saved sample tranformed image at {}".format(
                    sample_image_path))

                # Save loss histories
                content_loss_history.append(batch_total_loss_sum / batch_count)
                style_loss_history.append(batch_style_loss_sum / batch_count)
                total_loss_history.append(batch_total_loss_sum / batch_count)

            # Iterate Batch Counter
            batch_count += 1

    stop_time = time.time()
    # Print loss histories
    print("Done Training the Transformer Network!")
    print("Training Time: {} seconds".format(stop_time - start_time))
    print("========Content Loss========")
    print(content_loss_history)
    print("========Style Loss========")
    print(style_loss_history)
    print("========Total Loss========")
    print(total_loss_history)

    # Save TransformerNetwork weights
    TransformerNetwork.eval()
    TransformerNetwork.cpu()
    final_path = SAVE_MODEL_PATH + "transformer_weight.pth"
    print("Saving TransformerNetwork weights at {}".format(final_path))
    torch.save(TransformerNetwork.state_dict(), final_path)
    print("Done saving final model")

    # Plot Loss Histories
    if PLOT_LOSS:
        utils.plot_loss_hist(content_loss_history, style_loss_history,
                             total_loss_history)
Exemple #8
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def train():
    # Seeds
    torch.manual_seed(SEED)
    torch.cuda.manual_seed(SEED)
    np.random.seed(SEED)
    random.seed(SEED)

    # Device
    device = ("cuda" if torch.cuda.is_available() else "cpu")

    # Dataset and Dataloader
    transform = transforms.Compose([
        transforms.Resize(TRAIN_IMAGE_SIZE),
        transforms.CenterCrop(TRAIN_IMAGE_SIZE),
        transforms.ToTensor()
    ])
    x_trainloader, x_testloader = utils.prepare_loader(DATASET_PATH,
                                                       X_CLASS,
                                                       transform=transform,
                                                       batch_size=BATCH_SIZE,
                                                       shuffle=True)
    y_trainloader, y_testloader = utils.prepare_loader(DATASET_PATH,
                                                       Y_CLASS,
                                                       transform=transform,
                                                       batch_size=BATCH_SIZE,
                                                       shuffle=True)

    # Load Networks
    Gxy = models.Generator(64).to(device)
    Gyx = models.Generator(64).to(device)
    Dxy = models.Discriminator(64).to(device)
    Dyx = models.Discriminator(64).to(device)

    # Optimizer Settings
    G_param = list(Gxy.parameters()) + list(Gyx.parameters())
    G_optim = optim.Adam(G_param, lr=LR, betas=[BETA_1, BETA_2])
    Dxy_optim = optim.Adam(Dxy.parameters(), lr=LR, betas=[BETA_1, BETA_2])
    Dyx_optim = optim.Adam(Dyx.parameters(), lr=LR, betas=[BETA_1, BETA_2])

    # Losses
    from losses import real_loss, fake_loss, cycle_loss

    # Fixed test samples
    x_testiter = iter(x_testloader)
    y_testiter = iter(y_testloader)
    fixed_X = next(x_testiter)[0]
    fixed_X = fixed_X.to(device)
    fixed_Y = next(y_testiter)[0]
    fixed_Y = fixed_Y.to(device)

    # Tensor to Image
    fixed_X_image = utils.ttoi(fixed_X)
    fixed_Y_image = utils.ttoi(fixed_Y)

    # Number of batches
    x_trainiter = iter(x_trainloader)
    y_trainiter = iter(y_trainloader)
    iter_per_epoch = min(len(x_trainiter), len(y_trainiter))

    # Training the CycleGAN
    for epoch in range(1, NUM_EPOCHS + 1):
        print("========Epoch {}/{}========".format(epoch, NUM_EPOCHS))
        for _ in range(iter_per_epoch -
                       1):  # -1 in case of imbalanced sizes of the last batch

            # Fetch the dataset
            x_real = next(x_trainiter)[0]
            x_real = x_real.to(device)
            y_real = next(y_trainiter)[0]
            y_real = y_real.to(device)

            # ========= Discriminator ==========
            # In training the discriminators, we fix the generators' parameters.
            # It is alright to train both discriminators seperately beceause
            # their forward pass don't share any parameters with each other

            # Discriminator X -> Y Adversarial Loss
            Dxy_optim.zero_grad()  # Zero-out gradients
            Dxy_real_out = Dxy(y_real)  # Dxy Forward Pass
            Dxy_real_loss = real_loss(Dxy_real_out)  # Dxy Eeal loss
            Dxy_fake_out = Dxy(Gxy(x_real))  # Gxy produces fake-y images
            Dxy_fake_loss = fake_loss(Dxy_fake_out)  # Dxy Fake Loss
            Dxy_loss = Dxy_real_loss + Dxy_fake_loss  # Dxy Total Loss
            Dxy_loss.backward()  # Dxy Backprop
            Dxy_optim.step()  # Dxy Gradient Descent

            # Discriminator Y-> X Adversarial Loss
            Dyx_optim.zero_grad()  # Zero-out gradients
            Dyx_real_out = Dyx(x_real)  # Dyx Forward Pass
            Dyx_real_loss = real_loss(Dyx_real_out)  # Dyx Eeal loss
            Dyx_fake_out = Dyx(Gyx(y_real))  # Gyx produces fake-x images
            Dyx_fake_loss = fake_loss(Dyx_fake_out)  # Dyx Fake Loss
            Dyx_loss = Dyx_real_loss + Dyx_fake_loss  # Dyx Total Loss
            Dyx_loss.backward()  # Dyx Backprop
            Dyx_optim.step()  # Dyx Gradient Descent

            # ============= Generator ==============
            # Similar to training discriminator networks, in training
            # generator networks, we fix discriminator networks.
            # However, cycle consistency prohibits us
            # from training generators seperately.

            # Generator X -> Y Adversarial Loss
            G_optim.zero_grad()  # Zero-out gradients
            Gxy_out = Gxy(x_real)  # Gxy Forward Pass
            D_Gxy_out = Dxy(Gxy_out)  # Gxy -> Dxy Forward
            Gxy_loss = real_loss(D_Gxy_out)  # Gxy Real Loss

            # Generator Y -> X Adversarial Loss
            Gyx_out = Gyx(y_real)  # Gyx Forward Pass
            D_Gyx_out = Dyx(Gyx_out)  # Gyx -> Dyx Forward
            Gyx_loss = real_loss(D_Gyx_out)  # Gyx Real Loss

            # Cycle Consistency Loss
            y_x_y = Gxy(Gyx(x_real))  # Reconstruct Y
            yxy_cycle_loss = cycle_loss(
                y_x_y, y_real)  # Y-X-Y Cycle Reconstruction Loss
            x_y_x = Gyx(Gxy(y_real))  # Reconstruct X
            xyx_cycle_loss = cycle_loss(
                x_y_x, x_real)  # X-Y-X Cycle Reconstruction Loss

            # Generator Total Loss
            G_loss = Gxy_loss + Gyx_loss + CYCLE_WEIGHT * (xyx_cycle_loss +
                                                           yxy_cycle_loss)
            G_loss.backward()
            G_optim.step()

        # Print Losses
        print("Dxy Loss: {} Dyx Loss: {} Generator Loss: {}".format(
            Dxy_loss.item(), Dyx_loss.item(), G_loss.item()))

        # Generate Sample Fake Images
        Gxy.eval()
        Gyx.eval()
        with torch.no_grad():
            generated_y = Gyx(fixed_X)
            generated_y_img = utils.ttoi(generated_y.clone().detach())

            generated_x = Gxy(fixed_Y)
            generated_x_img = utils.ttoi(generated_x.clone().detach())

            H = W = TRAIN_IMAGE_SIZE
            concat_y = utils.concatenate_images(fixed_Y_image, generated_y_img,
                                                H, W)
            concat_x = utils.concatenate_images(fixed_X_image, generated_x_img,
                                                H, W)

            utils.saveimg(concat_x, "generated_x.png")
            utils.saveimg(concat_y, "generated_y.png")
def train():
    # Seeds
    torch.manual_seed(SEED)
    torch.cuda.manual_seed(SEED)
    np.random.seed(SEED)
    random.seed(SEED)

    # Device
    device = ("cuda" if torch.cuda.is_available() else "cpu")

    # Dataset and Dataloader
    transform = transforms.Compose([
        transforms.Resize(TRAIN_IMAGE_SIZE),
        transforms.CenterCrop(TRAIN_IMAGE_SIZE),
        # transforms.Grayscale(num_output_channels=3),
        transforms.ToTensor(),
        transforms.Lambda(lambda x: x.mul(255))
    ])
    train_dataset = datasets.ImageFolder(DATASET_PATH, transform=transform)
    train_loader = torch.utils.data.DataLoader(train_dataset,
                                               batch_size=BATCH_SIZE,
                                               shuffle=True)

    # Load networks
    TransformerNetwork = transformer.TransformerNetwork().to(device)

    if USE_LATEST_CHECKPOINT is True:
        files = glob.glob(
            "/home/clng/github/fast-neural-style-pytorch/models/checkpoint*")
        if len(files) == 0:
            print("use latest checkpoint but no checkpoint found")
        else:
            files.sort(key=os.path.getmtime, reverse=True)
            latest_checkpoint_path = files[0]
            print("using latest checkpoint %s" % (latest_checkpoint_path))
            params = torch.load(latest_checkpoint_path, map_location=device)
            TransformerNetwork.load_state_dict(params)

    VGG = vgg.VGG19().to(device)

    # Get Style Features
    imagenet_neg_mean = torch.tensor([-103.939, -116.779, -123.68],
                                     dtype=torch.float32).reshape(1, 3, 1,
                                                                  1).to(device)
    style_image = utils.load_image(STYLE_IMAGE_PATH)
    if ADJUST_BRIGHTNESS == "1":
        style_image = cv2.cvtColor(style_image, cv2.COLOR_BGR2GRAY)
        style_image = utils.hist_norm(style_image,
                                      [0, 64, 96, 128, 160, 192, 255],
                                      [0, 0.05, 0.15, 0.5, 0.85, 0.95, 1],
                                      inplace=True)
    elif ADJUST_BRIGHTNESS == "2":
        style_image = cv2.cvtColor(style_image, cv2.COLOR_BGR2GRAY)
        style_image = cv2.equalizeHist(style_image)
    elif ADJUST_BRIGHTNESS == "3":
        a = 1
        # hsv = cv2.cvtColor(style_image, cv2.COLOR_BGR2HSV)
        # hsv = utils.auto_brightness(hsv)
        # style_image = cv2.cvtColor(hsv, cv2.COLOR_HSV2BGR)
    style_image = ensure_three_channels(style_image)
    sname = os.path.splitext(os.path.basename(STYLE_IMAGE_PATH))[0] + "_train"
    cv2.imwrite(
        "/home/clng/datasets/bytenow/neural_styles/{s}.jpg".format(s=sname),
        style_image)

    style_tensor = utils.itot(style_image,
                              max_size=TRAIN_STYLE_SIZE).to(device)

    style_tensor = style_tensor.add(imagenet_neg_mean)
    B, C, H, W = style_tensor.shape
    style_features = VGG(style_tensor.expand([BATCH_SIZE, C, H, W]))
    style_gram = {}
    for key, value in style_features.items():
        style_gram[key] = utils.gram(value)

    # Optimizer settings
    optimizer = optim.Adam(TransformerNetwork.parameters(), lr=ADAM_LR)

    # Loss trackers
    content_loss_history = []
    style_loss_history = []
    total_loss_history = []
    batch_content_loss_sum = 0
    batch_style_loss_sum = 0
    batch_total_loss_sum = 0

    # Optimization/Training Loop
    batch_count = 1
    start_time = time.time()
    for epoch in range(NUM_EPOCHS):
        print("========Epoch {}/{}========".format(epoch + 1, NUM_EPOCHS))
        for content_batch, _ in train_loader:
            # Get current batch size in case of odd batch sizes
            curr_batch_size = content_batch.shape[0]

            # Free-up unneeded cuda memory
            # torch.cuda.empty_cache()

            # Zero-out Gradients
            optimizer.zero_grad()

            # Generate images and get features
            content_batch = content_batch[:, [2, 1, 0]].to(device)
            generated_batch = TransformerNetwork(content_batch)
            content_features = VGG(content_batch.add(imagenet_neg_mean))
            generated_features = VGG(generated_batch.add(imagenet_neg_mean))

            # Content Loss
            MSELoss = nn.MSELoss().to(device)
            content_loss = CONTENT_WEIGHT * \
                MSELoss(generated_features['relu3_4'],
                        content_features['relu3_4'])
            batch_content_loss_sum += content_loss

            # Style Loss
            style_loss = 0
            for key, value in generated_features.items():
                s_loss = MSELoss(utils.gram(value),
                                 style_gram[key][:curr_batch_size])
                style_loss += s_loss
            style_loss *= STYLE_WEIGHT
            batch_style_loss_sum += style_loss.item()

            # Total Loss
            total_loss = content_loss + style_loss
            batch_total_loss_sum += total_loss.item()

            # Backprop and Weight Update
            total_loss.backward()
            optimizer.step()

            # Save Model and Print Losses
            if (((batch_count - 1) % SAVE_MODEL_EVERY == 0)
                    or (batch_count == NUM_EPOCHS * len(train_loader))):
                # Print Losses
                print("========Iteration {}/{}========".format(
                    batch_count, NUM_EPOCHS * len(train_loader)))
                print("\tContent Loss:\t{:.2f}".format(batch_content_loss_sum /
                                                       batch_count))
                print("\tStyle Loss:\t{:.2f}".format(batch_style_loss_sum /
                                                     batch_count))
                print("\tTotal Loss:\t{:.2f}".format(batch_total_loss_sum /
                                                     batch_count))
                print("Time elapsed:\t{} seconds".format(time.time() -
                                                         start_time))

                # Save Model
                checkpoint_path = SAVE_MODEL_PATH + "checkpoint_" + str(
                    batch_count - 1) + ".pth"
                torch.save(TransformerNetwork.state_dict(), checkpoint_path)
                print("Saved TransformerNetwork checkpoint file at {}".format(
                    checkpoint_path))

                # Save sample generated image
                sample_tensor = generated_batch[0].clone().detach().unsqueeze(
                    dim=0)
                sample_image = utils.ttoi(sample_tensor.clone().detach())
                sample_image_path = SAVE_IMAGE_PATH + "sample0_" + str(
                    batch_count - 1) + ".png"
                utils.saveimg(sample_image, sample_image_path)
                print("Saved sample tranformed image at {}".format(
                    sample_image_path))

                # Save loss histories
                content_loss_history.append(batch_total_loss_sum / batch_count)
                style_loss_history.append(batch_style_loss_sum / batch_count)
                total_loss_history.append(batch_total_loss_sum / batch_count)

            # Iterate Batch Counter
            batch_count += 1

    stop_time = time.time()
    # Print loss histories
    print("Done Training the Transformer Network!")
    print("Training Time: {} seconds".format(stop_time - start_time))
    print("========Content Loss========")
    print(content_loss_history)
    print("========Style Loss========")
    print(style_loss_history)
    print("========Total Loss========")
    print(total_loss_history)

    # Save TransformerNetwork weights
    TransformerNetwork.eval()
    TransformerNetwork.cpu()
    final_path = SAVE_MODEL_PATH + STYLE_NAME + ".pth"
    print("Saving TransformerNetwork weights at {}".format(final_path))
    torch.save(TransformerNetwork.state_dict(), final_path)
    print("Done saving final model")

    # Plot Loss Histories
    if (PLOT_LOSS):
        utils.plot_loss_hist(content_loss_history, style_loss_history,
                             total_loss_history)