add files

gen_video.py

@@ -0,0 +1,210 @@
+import argparse
+import os
+
+import cv2
+import numpy as np
+import torch
+
+from model import Generator
+from psp_encoder.psp_encoders import PSPEncoder
+from utils import ten2cv, cv2ten
+
+import glob
+from tqdm import tqdm
+import random
+
+
+seed = 0
+
+random.seed(seed)
+np.random.seed(seed)
+torch.manual_seed(seed)
+torch.cuda.manual_seed_all(seed)
+
+
+def sigmoid(x, w=1):
+    return 1. / (1 + np.exp(-w * x))
+
+
+def get_alphas(start=-5, end=5, step=0.5, len_tail=10):
+    return [0] + [sigmoid(alpha) for alpha in np.arange(start, end, step)] + [1] * len_tail
+
+
+def slide(entries, margin=32):
+    """Returns a sliding reference window.
+    Args:
+        entries: a list containing two reference images, x_prev and x_next,
+                 both of which has a shape (1, 3, H, W)
+    Returns:
+        canvas: output slide of shape (num_frames, 3, H*2, W+margin)
+    """
+    _, C, H, W = entries[0].shape
+    alphas = get_alphas()
+    T = len(alphas) # number of frames
+
+    canvas = - torch.ones((T, C, H*2, W + margin))
+    merged = torch.cat(entries, dim=2)  # (1, 3, H*2, W)
+    for t, alpha in enumerate(alphas):
+        top = int(H * (1 - alpha))  # top, bottom for canvas
+        bottom = H * 2
+        m_top = 0  # top, bottom for merged
+        m_bottom = 2 * H - top
+        canvas[t, :, top:bottom, :W] = merged[:, :, m_top:m_bottom, :]
+    return canvas
+
+
+def slide_one_window(entries, margin=32):
+    """Returns a sliding reference window.
+    Args:
+        entries: a list containing two reference images, x_prev and x_next,
+                 both of which has a shape (1, 3, H, W)
+    Returns:
+        canvas: output slide of shape (num_frames, 3, H, W+margin)
+    """
+    _, C, H, W = entries[0].shape
+    device = entries[0].device
+    alphas = get_alphas()
+    T = len(alphas) # number of frames
+
+    canvas = - torch.ones((T, C, H, W + margin)).to(device)
+    merged = torch.cat(entries, dim=2)  # (1, 3, H*2, W)
+    for t, alpha in enumerate(alphas):
+        m_top = int(H * alpha)  # top, bottom for merged
+        m_bottom = m_top + H
+        canvas[t, :, :, :W] = merged[:, :, m_top:m_bottom, :]
+    return canvas
+
+
+def tensor2ndarray255(images):
+    images = torch.clamp(images * 0.5 + 0.5, 0, 1)
+    return (images.cpu().numpy().transpose(0, 2, 3, 1) * 255).astype(np.uint8)
+
+
+@torch.no_grad()
+def interpolate(args, g, sample_in, sample_style_prev, sample_style_next):
+    ''' returns T x C x H x W '''
+    frames_ten = []
+    alphas = get_alphas()
+
+    for alpha in alphas:
+        sample_style = torch.lerp(sample_style_prev, sample_style_next, alpha)
+        frame_ten, _ = g([sample_in], z_embed=sample_style, add_weight_index=args.add_weight_index,
+                               input_is_latent=True, return_latents=False, randomize_noise=False)
+        frames_ten.append(frame_ten)
+    frames_ten = torch.cat(frames_ten)
+    return frames_ten
+
+
+@torch.no_grad()
+def video_ref(args, g, psp_encoder, img_in_ten, img_style_tens):
+    video = []
+    sample_in = psp_encoder(img_in_ten)
+
+    img_style_ten_prev, sample_style_prev = None, None
+
+    for idx in tqdm(range(len(img_style_tens))):
+        img_style_ten_next = img_style_tens[idx]
+        sample_style_next = g_ema.get_z_embed(img_style_ten_next)
+        if img_style_ten_prev is None:
+            img_style_ten_prev, sample_style_prev = img_style_ten_next, sample_style_next
+            continue
+
+        interpolated = interpolate(args, g, sample_in, sample_style_prev, sample_style_next)
+        entries = [img_style_ten_prev, img_style_ten_next]
+        slided = slide_one_window(entries, margin=0)     # [T, C, H, W)
+        frames = torch.cat([img_in_ten.expand_as(interpolated), slided, interpolated], dim=3).cpu()   # [T, C, H, W*3)
+        video.append(frames)
+        img_style_ten_prev, sample_style_prev = img_style_ten_next, sample_style_next
+
+    # append last frame 10 time
+    for _ in range(10):
+        video.append(frames[-1:])
+    video = tensor2ndarray255(torch.cat(video))   # [T, H, W*3, C)
+
+    return video
+
+
+def save_video(fname, images, output_fps=30):
+    print('save video to: %s' % fname)
+
+    assert isinstance(images, np.ndarray), "images should be np.array: NHWC"
+    num_frames, height, width, channels = images.shape
+
+    fourcc = cv2.VideoWriter_fourcc(*'XVID')
+    videoWriter = cv2.VideoWriter(fname, fourcc, output_fps, (width, height))
+
+    for idx in tqdm(range(num_frames)):
+        frame = images[idx][:, :, ::-1]  # [H, W*3, C)
+        videoWriter.write(frame)
+
+    videoWriter.release()
+
+
+if __name__ == '__main__':
+    device = 'cuda'
+
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument('--size', type=int, default=1024)
+
+    parser.add_argument('--ckpt', type=str, default='', help='path to BlendGAN checkpoint')
+    parser.add_argument('--psp_encoder_ckpt', type=str, default='', help='path to psp_encoder checkpoint')
+
+    parser.add_argument('--style_img_path', type=str, default=None, help='path to style image')
+    parser.add_argument('--input_img_path', type=str, default=None, help='path to input image')
+    parser.add_argument('--add_weight_index', type=int, default=7)
+
+    parser.add_argument('--channel_multiplier', type=int, default=2)
+    parser.add_argument('--outdir', type=str, default="")
+
+    args = parser.parse_args()
+
+    outdir = args.outdir
+    if not os.path.exists(outdir):
+        os.makedirs(outdir, exist_ok=True)
+
+    args.latent = 512
+    args.n_mlp = 8
+
+    checkpoint = torch.load(args.ckpt)
+    model_dict = checkpoint['g_ema']
+    print('ckpt: ', args.ckpt)
+
+    g_ema = Generator(
+        args.size, args.latent, args.n_mlp, channel_multiplier=args.channel_multiplier
+    ).to(device)
+    g_ema.load_state_dict(model_dict)
+    g_ema.eval()
+
+    psp_encoder = PSPEncoder(args.psp_encoder_ckpt, output_size=args.size).to(device)
+    psp_encoder.eval()
+
+    input_img_paths = sorted(glob.glob(os.path.join(args.input_img_path, '*.*')))
+    style_img_paths = sorted(glob.glob(os.path.join(args.style_img_path, '*.*')))[:]
+
+    for input_img_path in input_img_paths:
+        print('process: %s' % input_img_path)
+
+        name_in = os.path.splitext(os.path.basename(input_img_path))[0]
+        img_in = cv2.imread(input_img_path, 1)
+        img_in = cv2.resize(img_in, (args.size, args.size))
+        img_in_ten = cv2ten(img_in, device)
+
+        img_style_tens = []
+
+        style_img_path_rand = random.choices(style_img_paths, k=8)
+        for style_img_path in style_img_path_rand:
+            name_style = os.path.splitext(os.path.basename(style_img_path))[0]
+            img_style = cv2.imread(style_img_path, 1)
+            img_style = cv2.resize(img_style, (args.size, args.size))
+            img_style_ten = cv2ten(img_style, device)
+
+            img_style_tens.append(img_style_ten)
+
+        fname = f'{args.outdir}/{name_in}.mp4'
+        video = video_ref(args, g_ema, psp_encoder, img_in_ten, img_style_tens)
+
+        save_video(fname, video, output_fps=30)
+
+    print('Done!')
+

generate_image_pairs.py

@@ -0,0 +1,111 @@
+import argparse
+import os
+
+import cv2
+import numpy as np
+import torch
+from tqdm import tqdm
+
+from model import Generator
+from utils import ten2cv, cv2ten
+import random
+
+seed = 0
+
+random.seed(seed)
+np.random.seed(seed)
+torch.manual_seed(seed)
+torch.cuda.manual_seed_all(seed)
+
+
+def generate(args, g_ema, device, mean_latent, sample_style, add_weight_index):
+    if args.sample_zs is not None:
+        sample_zs = torch.load(args.sample_zs)
+    else:
+        sample_zs = None
+
+    with torch.no_grad():
+        g_ema.eval()
+        for i in tqdm(range(args.pics)):
+            if sample_zs is not None:
+                sample_z = sample_zs[i]
+            else:
+                sample_z = torch.randn(1, args.latent, device=device)
+
+            sample1, _ = g_ema([sample_z],
+                               truncation=args.truncation, truncation_latent=mean_latent, return_latents=False, randomize_noise=False)
+            sample2, _ = g_ema([sample_z], z_embed=sample_style, add_weight_index=add_weight_index,
+                               truncation=args.truncation, truncation_latent=mean_latent, return_latents=False, randomize_noise=False)
+
+            sample1 = ten2cv(sample1)
+            sample2 = ten2cv(sample2)
+            out = np.concatenate([sample1, sample2], axis=1)
+
+            cv2.imwrite(f'{args.outdir}/{str(i).zfill(6)}.jpg', out)
+
+
+if __name__ == '__main__':
+    device = 'cuda'
+
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument('--size', type=int, default=1024)
+    parser.add_argument('--pics', type=int, default=20, help='N_PICS')
+    parser.add_argument('--truncation', type=float, default=0.75)
+    parser.add_argument('--truncation_mean', type=int, default=4096)
+    parser.add_argument('--ckpt', type=str, default='', help='path to BlendGAN checkpoint')
+    parser.add_argument('--style_img', type=str, default=None, help='path to style image')
+    parser.add_argument('--sample_zs', type=str, default=None)
+    parser.add_argument('--add_weight_index', type=int, default=6)
+
+    parser.add_argument('--channel_multiplier', type=int, default=2)
+    parser.add_argument('--outdir', type=str, default="")
+
+    args = parser.parse_args()
+
+    outdir = args.outdir
+    if not os.path.exists(outdir):
+        os.makedirs(outdir, exist_ok=True)
+
+    args.latent = 512
+    args.n_mlp = 8
+
+    checkpoint = torch.load(args.ckpt)
+    model_dict = checkpoint['g_ema']
+    if "latent_avg" in checkpoint.keys():
+        latent_avg = checkpoint["latent_avg"]
+    else:
+        latent_avg = None
+    if "truncation" in checkpoint.keys():
+        args.truncation = checkpoint["truncation"]
+
+    print('ckpt: ', args.ckpt)
+    print('truncation: ', args.truncation)
+
+    g_ema = Generator(
+        args.size, args.latent, args.n_mlp, channel_multiplier=args.channel_multiplier
+    ).to(device)
+    g_ema.load_state_dict(model_dict)
+
+    if args.truncation < 1:
+        if latent_avg is not None:
+            mean_latent = latent_avg
+            print('### use mean_latent in ckpt["latent_avg"]')
+        else:
+            with torch.no_grad():
+                mean_latent = g_ema.mean_latent(args.truncation_mean)
+                print('### generate mean_latent with \'g_ema.mean_latent\'')
+    else:
+        mean_latent = None
+        print('### args.truncation = 1, mean_latent is None')
+
+    if args.style_img is not None:
+        img = cv2.imread(args.style_img, 1)
+        img = cv2ten(img, device)
+        sample_style = g_ema.get_z_embed(img)
+    else:
+        sample_style = torch.randn(1, args.latent, device=device)
+
+    generate(args, g_ema, device, mean_latent, sample_style, args.add_weight_index)
+
+    print('Done!')

model.py

@@ -0,0 +1,782 @@
+import math
+import random
+
+import torch
+from torch import nn
+from torch.nn import functional as F
+
+from op import FusedLeakyReLU, fused_leaky_relu, upfirdn2d
+from model_encoder import StyleEncoder
+
+
+class PixelNorm(nn.Module):
+    def __init__(self):
+        super().__init__()
+
+    def forward(self, input):
+        return input * torch.rsqrt(torch.mean(input ** 2, dim=1, keepdim=True) + 1e-8)
+
+
+def make_kernel(k):
+    k = torch.tensor(k, dtype=torch.float32)
+
+    if k.ndim == 1:
+        k = k[None, :] * k[:, None]
+
+    k /= k.sum()
+
+    return k
+
+
+class Upsample(nn.Module):
+    def __init__(self, kernel, factor=2):
+        super().__init__()
+
+        self.factor = factor
+        kernel = make_kernel(kernel) * (factor ** 2)
+        self.register_buffer('kernel', kernel)
+
+        p = kernel.shape[0] - factor
+
+        pad0 = (p + 1) // 2 + factor - 1
+        pad1 = p // 2
+
+        self.pad = (pad0, pad1)
+
+    def forward(self, input):
+        out = upfirdn2d(input, self.kernel, up=self.factor, down=1, pad=self.pad)
+
+        return out
+
+
+class Downsample(nn.Module):
+    def __init__(self, kernel, factor=2):
+        super().__init__()
+
+        self.factor = factor
+        kernel = make_kernel(kernel)
+        self.register_buffer('kernel', kernel)
+
+        p = kernel.shape[0] - factor
+
+        pad0 = (p + 1) // 2
+        pad1 = p // 2
+
+        self.pad = (pad0, pad1)
+
+    def forward(self, input):
+        out = upfirdn2d(input, self.kernel, up=1, down=self.factor, pad=self.pad)
+
+        return out
+
+
+class Blur(nn.Module):
+    def __init__(self, kernel, pad, upsample_factor=1):
+        super().__init__()
+
+        kernel = make_kernel(kernel)
+
+        if upsample_factor > 1:
+            kernel = kernel * (upsample_factor ** 2)
+
+        self.register_buffer('kernel', kernel)
+
+        self.pad = pad
+
+    def forward(self, input):
+        out = upfirdn2d(input, self.kernel, pad=self.pad)
+
+        return out
+
+
+class EqualConv2d(nn.Module):
+    def __init__(
+        self, in_channel, out_channel, kernel_size, stride=1, padding=0, bias=True
+    ):
+        super().__init__()
+
+        self.weight = nn.Parameter(
+            torch.randn(out_channel, in_channel, kernel_size, kernel_size)
+        )
+        self.scale = 1 / math.sqrt(in_channel * kernel_size ** 2)
+
+        self.stride = stride
+        self.padding = padding
+
+        if bias:
+            self.bias = nn.Parameter(torch.zeros(out_channel))
+
+        else:
+            self.bias = None
+
+    def forward(self, input):
+        out = F.conv2d(
+            input,
+            self.weight * self.scale,
+            bias=self.bias,
+            stride=self.stride,
+            padding=self.padding,
+        )
+
+        return out
+
+    def __repr__(self):
+        return (
+            f'{self.__class__.__name__}({self.weight.shape[1]}, {self.weight.shape[0]},'
+            f' {self.weight.shape[2]}, stride={self.stride}, padding={self.padding})'
+        )
+
+
+class EqualLinear(nn.Module):
+    def __init__(
+        self, in_dim, out_dim, bias=True, bias_init=0, lr_mul=1, activation=None
+    ):
+        super().__init__()
+
+        self.weight = nn.Parameter(torch.randn(out_dim, in_dim).div_(lr_mul))
+
+        if bias:
+            self.bias = nn.Parameter(torch.zeros(out_dim).fill_(bias_init))
+
+        else:
+            self.bias = None
+
+        self.activation = activation
+
+        self.scale = (1 / math.sqrt(in_dim)) * lr_mul
+        self.lr_mul = lr_mul
+
+    def forward(self, input):
+        if self.activation:
+            out = F.linear(input, self.weight * self.scale)
+            out = fused_leaky_relu(out, self.bias * self.lr_mul)
+
+        else:
+            out = F.linear(
+                input, self.weight * self.scale, bias=self.bias * self.lr_mul
+            )
+
+        return out
+
+    def __repr__(self):
+        return (
+            f'{self.__class__.__name__}({self.weight.shape[1]}, {self.weight.shape[0]})'
+        )
+
+
+class ScaledLeakyReLU(nn.Module):
+    def __init__(self, negative_slope=0.2):
+        super().__init__()
+
+        self.negative_slope = negative_slope
+
+    def forward(self, input):
+        out = F.leaky_relu(input, negative_slope=self.negative_slope)
+
+        return out * math.sqrt(2)
+
+
+class ModulatedConv2d(nn.Module):
+    def __init__(
+        self,
+        in_channel,
+        out_channel,
+        kernel_size,
+        style_dim,
+        demodulate=True,
+        upsample=False,
+        downsample=False,
+        blur_kernel=[1, 3, 3, 1],
+    ):
+        super().__init__()
+
+        self.eps = 1e-8
+        self.kernel_size = kernel_size
+        self.in_channel = in_channel
+        self.out_channel = out_channel
+        self.upsample = upsample
+        self.downsample = downsample
+
+        if upsample:
+            factor = 2
+            p = (len(blur_kernel) - factor) - (kernel_size - 1)
+            pad0 = (p + 1) // 2 + factor - 1
+            pad1 = p // 2 + 1
+
+            self.blur = Blur(blur_kernel, pad=(pad0, pad1), upsample_factor=factor)
+
+        if downsample:
+            factor = 2
+            p = (len(blur_kernel) - factor) + (kernel_size - 1)
+            pad0 = (p + 1) // 2
+            pad1 = p // 2
+
+            self.blur = Blur(blur_kernel, pad=(pad0, pad1))
+
+        fan_in = in_channel * kernel_size ** 2
+        self.scale = 1 / math.sqrt(fan_in)
+        self.padding = kernel_size // 2
+
+        self.weight = nn.Parameter(
+            torch.randn(1, out_channel, in_channel, kernel_size, kernel_size)
+        )
+
+        self.modulation = EqualLinear(style_dim, in_channel, bias_init=1)
+
+        self.demodulate = demodulate
+
+    def __repr__(self):
+        return (
+            f'{self.__class__.__name__}({self.in_channel}, {self.out_channel}, {self.kernel_size}, '
+            f'upsample={self.upsample}, downsample={self.downsample})'
+        )
+
+    def forward(self, input, style):
+        batch, in_channel, height, width = input.shape
+
+        style = self.modulation(style).view(batch, 1, in_channel, 1, 1)
+        weight = self.scale * self.weight * style
+
+        if self.demodulate:
+            demod = torch.rsqrt(weight.pow(2).sum([2, 3, 4]) + 1e-8)
+            weight = weight * demod.view(batch, self.out_channel, 1, 1, 1)
+
+        weight = weight.view(
+            batch * self.out_channel, in_channel, self.kernel_size, self.kernel_size
+        )
+
+        if self.upsample:
+            input = input.view(1, batch * in_channel, height, width)
+            weight = weight.view(
+                batch, self.out_channel, in_channel, self.kernel_size, self.kernel_size
+            )
+            weight = weight.transpose(1, 2).reshape(
+                batch * in_channel, self.out_channel, self.kernel_size, self.kernel_size
+            )
+            out = F.conv_transpose2d(input, weight, padding=0, stride=2, groups=batch)
+            _, _, height, width = out.shape
+            out = out.view(batch, self.out_channel, height, width)
+            out = self.blur(out)
+
+        elif self.downsample:
+            input = self.blur(input)
+            _, _, height, width = input.shape
+            input = input.view(1, batch * in_channel, height, width)
+            out = F.conv2d(input, weight, padding=0, stride=2, groups=batch)
+            _, _, height, width = out.shape
+            out = out.view(batch, self.out_channel, height, width)
+
+        else:
+            input = input.view(1, batch * in_channel, height, width)
+            out = F.conv2d(input, weight, padding=self.padding, groups=batch)
+            _, _, height, width = out.shape
+            out = out.view(batch, self.out_channel, height, width)
+
+        return out
+
+
+class NoiseInjection(nn.Module):
+    def __init__(self):
+        super().__init__()
+
+        self.weight = nn.Parameter(torch.zeros(1))
+
+    def forward(self, image, noise=None):
+        if noise is None:
+            batch, _, height, width = image.shape
+            noise = image.new_empty(batch, 1, height, width).normal_()
+
+        return image + self.weight * noise
+
+
+class ConstantInput(nn.Module):
+    def __init__(self, channel, size=4):
+        super().__init__()
+
+        self.input = nn.Parameter(torch.randn(1, channel, size, size))
+
+    def forward(self, input):
+        batch = input.shape[0]
+        out = self.input.repeat(batch, 1, 1, 1)
+
+        return out
+
+
+class StyledConv(nn.Module):
+    def __init__(
+        self,
+        in_channel,
+        out_channel,
+        kernel_size,
+        style_dim,
+        upsample=False,
+        blur_kernel=[1, 3, 3, 1],
+        demodulate=True,
+    ):
+        super().__init__()
+
+        self.conv = ModulatedConv2d(
+            in_channel,
+            out_channel,
+            kernel_size,
+            style_dim,
+            upsample=upsample,
+            blur_kernel=blur_kernel,
+            demodulate=demodulate,
+        )
+
+        self.noise = NoiseInjection()
+        # self.bias = nn.Parameter(torch.zeros(1, out_channel, 1, 1))
+        # self.activate = ScaledLeakyReLU(0.2)
+        self.activate = FusedLeakyReLU(out_channel)
+
+    def forward(self, input, style, noise=None):
+        out = self.conv(input, style)
+        out = self.noise(out, noise=noise)
+        # out = out + self.bias
+        out = self.activate(out)
+
+        return out
+
+
+class ToRGB(nn.Module):
+    def __init__(self, in_channel, style_dim, upsample=True, blur_kernel=[1, 3, 3, 1]):
+        super().__init__()
+
+        if upsample:
+            self.upsample = Upsample(blur_kernel)
+
+        self.conv = ModulatedConv2d(in_channel, 3, 1, style_dim, demodulate=False)
+        self.bias = nn.Parameter(torch.zeros(1, 3, 1, 1))
+
+    def forward(self, input, style, skip=None):
+        out = self.conv(input, style)
+        out = out + self.bias
+
+        if skip is not None:
+            skip = self.upsample(skip)
+
+            out = out + skip
+
+        return out
+
+
+class Generator(nn.Module):
+    def __init__(
+        self,
+        size,
+        style_dim,
+        n_mlp,
+        channel_multiplier=2,
+        blur_kernel=[1, 3, 3, 1],
+        lr_mlp=0.01,
+    ):
+        super().__init__()
+
+        self.size = size
+
+        self.style_dim = style_dim
+
+        self.embedder = StyleEncoder(style_dim=512, n_mlp=4)
+
+        layers = [PixelNorm()]
+
+        for i in range(n_mlp):
+            layers.append(
+                EqualLinear(
+                    style_dim, style_dim, lr_mul=lr_mlp, activation='fused_lrelu'
+                )
+            )
+        self.embedding = nn.Sequential(*layers)
+
+        layers = [PixelNorm()]
+
+        for i in range(n_mlp):
+            layers.append(
+                EqualLinear(
+                    style_dim, style_dim, lr_mul=lr_mlp, activation='fused_lrelu'
+                )
+            )
+
+        self.style = nn.Sequential(*layers)
+
+        self.channels = {
+            4: 512,
+            8: 512,
+            16: 512,
+            32: 512,
+            64: 256 * channel_multiplier,
+            128: 128 * channel_multiplier,
+            256: 64 * channel_multiplier,
+            512: 32 * channel_multiplier,
+            1024: 16 * channel_multiplier,
+        }
+
+        self.input = ConstantInput(self.channels[4])
+        self.conv1 = StyledConv(
+            self.channels[4], self.channels[4], 3, style_dim, blur_kernel=blur_kernel
+        )
+        self.to_rgb1 = ToRGB(self.channels[4], style_dim, upsample=False)
+
+        self.log_size = int(math.log(size, 2))
+        self.num_layers = (self.log_size - 2) * 2 + 1
+
+        self.convs = nn.ModuleList()
+        self.upsamples = nn.ModuleList()
+        self.to_rgbs = nn.ModuleList()
+        self.noises = nn.Module()
+
+        in_channel = self.channels[4]
+
+        for layer_idx in range(self.num_layers):
+            res = (layer_idx + 5) // 2
+            shape = [1, 1, 2 ** res, 2 ** res]
+            self.noises.register_buffer(f'noise_{layer_idx}', torch.randn(*shape))
+
+        for i in range(3, self.log_size + 1):
+            out_channel = self.channels[2 ** i]
+
+            self.convs.append(
+                StyledConv(
+                    in_channel,
+                    out_channel,
+                    3,
+                    style_dim,
+                    upsample=True,
+                    blur_kernel=blur_kernel,
+                )
+            )
+
+            self.convs.append(
+                StyledConv(
+                    out_channel, out_channel, 3, style_dim, blur_kernel=blur_kernel
+                )
+            )
+
+            self.to_rgbs.append(ToRGB(out_channel, style_dim))
+
+            in_channel = out_channel
+
+        self.n_latent = self.log_size * 2 - 2
+
+        self.add_weight = nn.Parameter(torch.ones(1, self.n_latent, 1))
+
+    def make_noise(self):
+        device = self.input.input.device
+
+        noises = [torch.randn(1, 1, 2 ** 2, 2 ** 2, device=device)]
+
+        for i in range(3, self.log_size + 1):
+            for _ in range(2):
+                noises.append(torch.randn(1, 1, 2 ** i, 2 ** i, device=device))
+
+        return noises
+
+    def mean_latent(self, n_latent):
+        latent_in = torch.randn(
+            n_latent, self.style_dim, device=self.input.input.device
+        )
+        latent = self.style(latent_in).mean(0, keepdim=True)
+
+        return latent
+
+    def get_latent(self, input):
+        return self.style(input)
+
+    def get_z_embed(self, image):
+        self.embedder.eval()
+        with torch.no_grad():
+            z_embed = self.embedder(image)  # [N, 512]
+        return z_embed
+
+    def forward(
+        self,
+        styles=None,
+        return_latents=False,
+        inject_index=None,
+        truncation=1,
+        truncation_latent=None,
+        input_is_latent=False,
+        noise=None,
+        randomize_noise=True,
+        style_image=None,
+        z_embed=None,
+        only_return_z_embed=False,
+        add_weight_index=None,
+    ):
+        if only_return_z_embed and style_image is not None:
+            return self.get_z_embed(style_image)
+
+        if not input_is_latent:
+            styles = [self.style(s) for s in styles]
+
+        if noise is None:
+            if randomize_noise:
+                noise = [None] * self.num_layers
+            else:
+                noise = [
+                    getattr(self.noises, f'noise_{i}') for i in range(self.num_layers)
+                ]
+
+        if truncation < 1:
+            style_t = []
+
+            for style in styles:
+                style_t.append(
+                    truncation_latent + truncation * (style - truncation_latent)
+                )
+
+            styles = style_t
+
+        if len(styles) < 2:
+            inject_index = self.n_latent
+
+            if styles[0].ndim < 3:
+                latent = styles[0].unsqueeze(1).repeat(1, inject_index, 1)
+
+            else:
+                latent = styles[0]
+
+        else:
+            if inject_index is None:
+                inject_index = random.randint(1, self.n_latent - 1)
+
+            latent = styles[0].unsqueeze(1).repeat(1, inject_index, 1)
+            latent2 = styles[1].unsqueeze(1).repeat(1, self.n_latent - inject_index, 1)
+
+            latent = torch.cat([latent, latent2], 1)  # [N, 18, 512]
+
+        if z_embed is not None:
+            latent_style = self.embedding(z_embed)
+            latent_style = latent_style.unsqueeze(1).repeat(1, self.n_latent, 1)  # [N, 18, 512]
+        elif style_image is not None:
+            z_embed = self.get_z_embed(style_image)  # [N, 512]
+            latent_style = self.embedding(z_embed)
+            latent_style = latent_style.unsqueeze(1).repeat(1, self.n_latent, 1)  # [N, 18, 512]
+        else:
+            latent_style = None
+
+        if latent_style is not None:
+            self.add_weight.data = self.add_weight.data.clamp(0.0, 1.0)
+            if add_weight_index is not None:
+                add_weight_new = self.add_weight.clone()
+                add_weight_new[:, :add_weight_index, :] = 1.0
+                latent = latent * add_weight_new + latent_style * (1 - add_weight_new)
+            else:
+                latent = latent * self.add_weight + latent_style * (1 - self.add_weight)
+
+        out = self.input(latent)
+        out = self.conv1(out, latent[:, 0], noise=noise[0])
+
+        skip = self.to_rgb1(out, latent[:, 1])
+
+        i = 1
+        for conv1, conv2, noise1, noise2, to_rgb in zip(
+            self.convs[::2], self.convs[1::2], noise[1::2], noise[2::2], self.to_rgbs
+        ):
+            out = conv1(out, latent[:, i], noise=noise1)
+            out = conv2(out, latent[:, i + 1], noise=noise2)
+            skip = to_rgb(out, latent[:, i + 2], skip)
+
+            i += 2
+
+        image = skip
+
+        if return_latents:
+            if style_image is not None or z_embed is not None:
+                return image, latent, z_embed
+            else:
+                return image, latent
+
+        else:
+            return image, None
+
+
+class ConvLayer(nn.Sequential):
+    def __init__(
+        self,
+        in_channel,
+        out_channel,
+        kernel_size,
+        downsample=False,
+        blur_kernel=[1, 3, 3, 1],
+        bias=True,
+        activate=True,
+    ):
+        layers = []
+
+        if downsample:
+            factor = 2
+            p = (len(blur_kernel) - factor) + (kernel_size - 1)
+            pad0 = (p + 1) // 2
+            pad1 = p // 2
+
+            layers.append(Blur(blur_kernel, pad=(pad0, pad1)))
+
+            stride = 2
+            self.padding = 0
+
+        else:
+            stride = 1
+            self.padding = kernel_size // 2
+
+        layers.append(
+            EqualConv2d(
+                in_channel,
+                out_channel,
+                kernel_size,
+                padding=self.padding,
+                stride=stride,
+                bias=bias and not activate,
+            )
+        )
+
+        if activate:
+            if bias:
+                layers.append(FusedLeakyReLU(out_channel))
+
+            else:
+                layers.append(ScaledLeakyReLU(0.2))
+
+        super().__init__(*layers)
+
+
+class ResBlock(nn.Module):
+    def __init__(self, in_channel, out_channel, blur_kernel=[1, 3, 3, 1]):
+        super().__init__()
+
+        self.conv1 = ConvLayer(in_channel, in_channel, 3)
+        self.conv2 = ConvLayer(in_channel, out_channel, 3, downsample=True)
+
+        self.skip = ConvLayer(
+            in_channel, out_channel, 1, downsample=True, activate=False, bias=False
+        )
+
+    def forward(self, input):
+        out = self.conv1(input)
+        out = self.conv2(out)
+
+        skip = self.skip(input)
+        out = (out + skip) / math.sqrt(2)
+
+        return out
+
+
+class Discriminator(nn.Module):
+    def __init__(self, size, channel_multiplier=2, blur_kernel=[1, 3, 3, 1]):
+        super().__init__()
+
+        channels = {
+            4: 512,
+            8: 512,
+            16: 512,
+            32: 512,
+            64: 256 * channel_multiplier,
+            128: 128 * channel_multiplier,
+            256: 64 * channel_multiplier,
+            512: 32 * channel_multiplier,
+            1024: 16 * channel_multiplier,
+        }
+
+        convs = [ConvLayer(3, channels[size], 1)]
+
+        log_size = int(math.log(size, 2))
+
+        in_channel = channels[size]
+
+        for i in range(log_size, 2, -1):
+            out_channel = channels[2 ** (i - 1)]
+
+            convs.append(ResBlock(in_channel, out_channel, blur_kernel))
+
+            in_channel = out_channel
+
+        self.convs = nn.Sequential(*convs)
+
+        self.stddev_group = 4
+        self.stddev_feat = 1
+
+        self.final_conv = ConvLayer(in_channel + 1, channels[4], 3)
+        self.final_linear = nn.Sequential(
+            EqualLinear(channels[4] * 4 * 4, channels[4], activation='fused_lrelu'),
+            EqualLinear(channels[4], 1),
+        )
+
+    def forward(self, input):
+        out = self.convs(input)
+
+        batch, channel, height, width = out.shape
+        group = min(batch, self.stddev_group)
+        stddev = out.view(
+            group, -1, self.stddev_feat, channel // self.stddev_feat, height, width
+        )
+        stddev = torch.sqrt(stddev.var(0, unbiased=False) + 1e-8)
+        stddev = stddev.mean([2, 3, 4], keepdims=True).squeeze(2)
+        stddev = stddev.repeat(group, 1, height, width)
+        out = torch.cat([out, stddev], 1)
+
+        out = self.final_conv(out)
+
+        out = out.view(batch, -1)
+        out = self.final_linear(out)
+
+        return out
+
+
+class ProjectionDiscriminator(nn.Module):
+    def __init__(self, size, style_dim=512, channel_multiplier=2, blur_kernel=[1, 3, 3, 1]):
+        super().__init__()
+
+        channels = {
+            4: 512,
+            8: 512,
+            16: 512,
+            32: 512,
+            64: 256 * channel_multiplier,
+            128: 128 * channel_multiplier,
+            256: 64 * channel_multiplier,
+            512: 32 * channel_multiplier,
+            1024: 16 * channel_multiplier,
+        }
+
+        convs = [ConvLayer(3, channels[size], 1)]
+
+        log_size = int(math.log(size, 2))
+
+        in_channel = channels[size]
+
+        for i in range(log_size, 2, -1):
+            out_channel = channels[2 ** (i - 1)]
+            convs.append(ResBlock(in_channel, out_channel, blur_kernel))
+            in_channel = out_channel
+
+        self.convs = nn.Sequential(*convs)
+
+        self.stddev_group = 4
+        self.stddev_feat = 1
+
+        self.final_conv = ConvLayer(in_channel + 1, channels[4], 3)
+
+        self.l_out = EqualLinear(in_channel, 1)
+        self.l_style = EqualLinear(style_dim, in_channel)
+
+    def forward(self, input, style):
+        out = self.convs(input)
+
+        batch, channel, height, width = out.shape
+        group = min(batch, self.stddev_group)
+        stddev = out.view(
+            group, -1, self.stddev_feat, channel // self.stddev_feat, height, width
+        )
+        stddev = torch.sqrt(stddev.var(0, unbiased=False) + 1e-8)
+        stddev = stddev.mean([2, 3, 4], keepdims=True).squeeze(2)
+        stddev = stddev.repeat(group, 1, height, width)
+        out = torch.cat([out, stddev], 1)
+
+        out = self.final_conv(out)
+
+        h = torch.sum(out, dim=(2, 3))
+        output = self.l_out(h)
+        output += torch.sum(self.l_style(style) * h, dim=1, keepdim=True)
+
+        return output

model_encoder.py

@@ -0,0 +1,160 @@
+import math
+
+from collections import namedtuple
+
+import torch
+from torch import nn
+from torch.nn import functional as F
+
+import torchvision.models.vgg as vgg
+
+from op import fused_leaky_relu
+
+
+FeatureOutput = namedtuple(
+    "FeatureOutput", ["relu1", "relu2", "relu3", "relu4", "relu5"])
+
+
+def gram_matrix(y):
+    (b, ch, h, w) = y.size()
+    features = y.view(b, ch, w * h)
+    features_t = features.transpose(1, 2)
+    gram = features.bmm(features_t) / (ch * h * w)
+    return gram
+
+
+class FeatureExtractor(nn.Module):
+    """Reference:
+        https://discuss.pytorch.org/t/how-to-extract-features-of-an-image-from-a-trained-model/119/3
+    """
+
+    def __init__(self):
+        super(FeatureExtractor, self).__init__()
+        self.vgg_layers = vgg.vgg19(pretrained=True).features
+        self.layer_name_mapping = {
+            '3': "relu1",
+            '8': "relu2",
+            '17': "relu3",
+            '26': "relu4",
+            '35': "relu5",
+        }
+
+    def forward(self, x):
+        output = {}
+        for name, module in self.vgg_layers._modules.items():
+            x = module(x)
+            if name in self.layer_name_mapping:
+                output[self.layer_name_mapping[name]] = x
+        return FeatureOutput(**output)
+
+
+class StyleEmbedder(nn.Module):
+    def __init__(self):
+        super(StyleEmbedder, self).__init__()
+        self.feature_extractor = FeatureExtractor()
+        self.feature_extractor.eval()
+        self.avg_pool = torch.nn.AdaptiveAvgPool2d((256, 256))
+
+    def forward(self, img):
+        N = img.shape[0]
+        features = self.feature_extractor(self.avg_pool(img))
+
+        grams = []
+        for feature in features:
+            gram = gram_matrix(feature)
+            grams.append(gram.view(N, -1))
+        out = torch.cat(grams, dim=1)
+        return out
+
+
+class PixelNorm(nn.Module):
+    def __init__(self):
+        super().__init__()
+
+    def forward(self, input):
+        return input * torch.rsqrt(torch.mean(input ** 2, dim=1, keepdim=True) + 1e-8)
+
+
+class EqualLinear(nn.Module):
+    def __init__(
+        self, in_dim, out_dim, bias=True, bias_init=0, lr_mul=1, activation=None
+    ):
+        super().__init__()
+
+        self.weight = nn.Parameter(torch.randn(out_dim, in_dim).div_(lr_mul))
+
+        if bias:
+            self.bias = nn.Parameter(torch.zeros(out_dim).fill_(bias_init))
+
+        else:
+            self.bias = None
+
+        self.activation = activation
+
+        self.scale = (1 / math.sqrt(in_dim)) * lr_mul
+        self.lr_mul = lr_mul
+
+    def forward(self, input):
+        if self.activation:
+            out = F.linear(input, self.weight * self.scale)
+            out = fused_leaky_relu(out, self.bias * self.lr_mul)
+
+        else:
+            out = F.linear(
+                input, self.weight * self.scale, bias=self.bias * self.lr_mul
+            )
+
+        return out
+
+    def __repr__(self):
+        return (
+            f'{self.__class__.__name__}({self.weight.shape[1]}, {self.weight.shape[0]})'
+        )
+
+
+class StyleEncoder(nn.Module):
+    def __init__(
+        self,
+        style_dim=512,
+        n_mlp=4,
+    ):
+        super().__init__()
+
+        self.style_dim = style_dim
+
+        e_dim = 610304
+        self.embedder = StyleEmbedder()
+
+        layers = []
+
+        layers.append(EqualLinear(e_dim, style_dim, lr_mul=1, activation='fused_lrelu'))
+        for i in range(n_mlp - 2):
+            layers.append(
+                EqualLinear(
+                    style_dim, style_dim, lr_mul=1, activation='fused_lrelu'
+                )
+            )
+        layers.append(EqualLinear(style_dim, style_dim, lr_mul=1, activation=None))
+        self.embedder_mlp = nn.Sequential(*layers)
+
+    def forward(self, image):
+        z_embed = self.embedder_mlp(self.embedder(image))  # [N, 512]
+        return z_embed
+
+
+class Projector(nn.Module):
+    def __init__(self, style_dim=512, n_mlp=4):
+        super().__init__()
+
+        layers = []
+        for i in range(n_mlp - 1):
+            layers.append(
+                EqualLinear(
+                    style_dim, style_dim, lr_mul=1, activation='fused_lrelu'
+                )
+            )
+        layers.append(EqualLinear(style_dim, style_dim, lr_mul=1, activation=None))
+        self.projector = nn.Sequential(*layers)
+
+    def forward(self, x):
+        return self.projector(x)

op/__init__.py

@@ -0,0 +1,2 @@
+from .fused_act import FusedLeakyReLU, fused_leaky_relu
+from .upfirdn2d import upfirdn2d

op/fused_act.py

@@ -0,0 +1,104 @@
+import os
+
+import torch
+from torch import nn
+from torch.nn import functional as F
+from torch.autograd import Function
+from torch.utils.cpp_extension import load
+
+
+module_path = os.path.dirname(__file__)
+
+cuda_available = torch.cuda.is_available()
+
+if cuda_available:
+    fused = load(
+        "fused",
+        sources=[
+            os.path.join(module_path, "fused_bias_act.cpp"),
+            os.path.join(module_path, "fused_bias_act_kernel.cu"),
+        ],
+    )
+else:
+    fused = None
+    print("fused_act.py is running on cpu")
+
+
+class FusedLeakyReLUFunctionBackward(Function):
+    @staticmethod
+    def forward(ctx, grad_output, out, negative_slope, scale):
+        ctx.save_for_backward(out)
+        ctx.negative_slope = negative_slope
+        ctx.scale = scale
+
+        empty = grad_output.new_empty(0)
+
+        grad_input = fused.fused_bias_act(
+            grad_output, empty, out, 3, 1, negative_slope, scale
+        )
+
+        dim = [0]
+
+        if grad_input.ndim > 2:
+            dim += list(range(2, grad_input.ndim))
+
+        grad_bias = grad_input.sum(dim).detach()
+
+        return grad_input, grad_bias
+
+    @staticmethod
+    def backward(ctx, gradgrad_input, gradgrad_bias):
+        out, = ctx.saved_tensors
+        gradgrad_out = fused.fused_bias_act(
+            gradgrad_input, gradgrad_bias, out, 3, 1, ctx.negative_slope, ctx.scale
+        )
+
+        return gradgrad_out, None, None, None
+
+
+class FusedLeakyReLUFunction(Function):
+    @staticmethod
+    def forward(ctx, input, bias, negative_slope, scale):
+        empty = input.new_empty(0)
+        out = fused.fused_bias_act(input, bias, empty, 3, 0, negative_slope, scale)
+        ctx.save_for_backward(out)
+        ctx.negative_slope = negative_slope
+        ctx.scale = scale
+
+        return out
+
+    @staticmethod
+    def backward(ctx, grad_output):
+        out, = ctx.saved_tensors
+
+        grad_input, grad_bias = FusedLeakyReLUFunctionBackward.apply(
+            grad_output, out, ctx.negative_slope, ctx.scale
+        )
+
+        return grad_input, grad_bias, None, None
+
+
+class FusedLeakyReLU(nn.Module):
+    def __init__(self, channel, negative_slope=0.2, scale=2 ** 0.5):
+        super().__init__()
+
+        self.bias = nn.Parameter(torch.zeros(channel))
+        self.negative_slope = negative_slope
+        self.scale = scale
+
+    def forward(self, input):
+        return fused_leaky_relu(input, self.bias, self.negative_slope, self.scale)
+
+
+def fused_leaky_relu(input, bias, negative_slope=0.2, scale=2 ** 0.5):
+    if input.device.type == "cpu":
+        rest_dim = [1] * (input.ndim - bias.ndim - 1)
+        return (
+            F.leaky_relu(
+                input + bias.view(1, bias.shape[0], *rest_dim), negative_slope=0.2
+            )
+            * scale
+        )
+
+    else:
+        return FusedLeakyReLUFunction.apply(input, bias, negative_slope, scale)

op/fused_bias_act.cpp

@@ -0,0 +1,21 @@
+#include <torch/extension.h>
+
+
+torch::Tensor fused_bias_act_op(const torch::Tensor& input, const torch::Tensor& bias, const torch::Tensor& refer,
+    int act, int grad, float alpha, float scale);
+
+#define CHECK_CUDA(x) TORCH_CHECK(x.type().is_cuda(), #x " must be a CUDA tensor")
+#define CHECK_CONTIGUOUS(x) TORCH_CHECK(x.is_contiguous(), #x " must be contiguous")
+#define CHECK_INPUT(x) CHECK_CUDA(x); CHECK_CONTIGUOUS(x)
+
+torch::Tensor fused_bias_act(const torch::Tensor& input, const torch::Tensor& bias, const torch::Tensor& refer,
+    int act, int grad, float alpha, float scale) {
+    CHECK_CUDA(input);
+    CHECK_CUDA(bias);
+
+    return fused_bias_act_op(input, bias, refer, act, grad, alpha, scale);
+}
+
+PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
+    m.def("fused_bias_act", &fused_bias_act, "fused bias act (CUDA)");
+}

op/fused_bias_act_kernel.cu

@@ -0,0 +1,99 @@
+// Copyright (c) 2019, NVIDIA Corporation. All rights reserved.
+//
+// This work is made available under the Nvidia Source Code License-NC.
+// To view a copy of this license, visit
+// https://nvlabs.github.io/stylegan2/license.html
+
+#include <torch/types.h>
+
+#include <ATen/ATen.h>
+#include <ATen/AccumulateType.h>
+#include <ATen/cuda/CUDAContext.h>
+#include <ATen/cuda/CUDAApplyUtils.cuh>
+
+#include <cuda.h>
+#include <cuda_runtime.h>
+
+
+template <typename scalar_t>
+static __global__ void fused_bias_act_kernel(scalar_t* out, const scalar_t* p_x, const scalar_t* p_b, const scalar_t* p_ref,
+    int act, int grad, scalar_t alpha, scalar_t scale, int loop_x, int size_x, int step_b, int size_b, int use_bias, int use_ref) {
+    int xi = blockIdx.x * loop_x * blockDim.x + threadIdx.x;
+
+    scalar_t zero = 0.0;
+
+    for (int loop_idx = 0; loop_idx < loop_x && xi < size_x; loop_idx++, xi += blockDim.x) {
+        scalar_t x = p_x[xi];
+
+        if (use_bias) {
+            x += p_b[(xi / step_b) % size_b];
+        }
+
+        scalar_t ref = use_ref ? p_ref[xi] : zero;
+
+        scalar_t y;
+
+        switch (act * 10 + grad) {
+            default:
+            case 10: y = x; break;
+            case 11: y = x; break;
+            case 12: y = 0.0; break;
+
+            case 30: y = (x > 0.0) ? x : x * alpha; break;
+            case 31: y = (ref > 0.0) ? x : x * alpha; break;
+            case 32: y = 0.0; break;
+        }
+
+        out[xi] = y * scale;
+    }
+}
+
+
+torch::Tensor fused_bias_act_op(const torch::Tensor& input, const torch::Tensor& bias, const torch::Tensor& refer,
+    int act, int grad, float alpha, float scale) {
+    int curDevice = -1;
+    cudaGetDevice(&curDevice);
+    cudaStream_t stream = at::cuda::getCurrentCUDAStream(curDevice);
+
+    auto x = input.contiguous();
+    auto b = bias.contiguous();
+    auto ref = refer.contiguous();
+
+    int use_bias = b.numel() ? 1 : 0;
+    int use_ref = ref.numel() ? 1 : 0;
+
+    int size_x = x.numel();
+    int size_b = b.numel();
+    int step_b = 1;
+
+    for (int i = 1 + 1; i < x.dim(); i++) {
+        step_b *= x.size(i);
+    }
+
+    int loop_x = 4;
+    int block_size = 4 * 32;
+    int grid_size = (size_x - 1) / (loop_x * block_size) + 1;
+
+    auto y = torch::empty_like(x);
+
+    AT_DISPATCH_FLOATING_TYPES_AND_HALF(x.scalar_type(), "fused_bias_act_kernel", [&] {
+        fused_bias_act_kernel<scalar_t><<<grid_size, block_size, 0, stream>>>(
+            y.data_ptr<scalar_t>(),
+            x.data_ptr<scalar_t>(),
+            b.data_ptr<scalar_t>(),
+            ref.data_ptr<scalar_t>(),
+            act,
+            grad,
+            alpha,
+            scale,
+            loop_x,
+            size_x,
+            step_b,
+            size_b,
+            use_bias,
+            use_ref
+        );
+    });
+
+    return y;
+}

op/upfirdn2d.cpp

@@ -0,0 +1,23 @@
+#include <torch/extension.h>
+
+
+torch::Tensor upfirdn2d_op(const torch::Tensor& input, const torch::Tensor& kernel,
+                            int up_x, int up_y, int down_x, int down_y,
+                            int pad_x0, int pad_x1, int pad_y0, int pad_y1);
+
+#define CHECK_CUDA(x) TORCH_CHECK(x.type().is_cuda(), #x " must be a CUDA tensor")
+#define CHECK_CONTIGUOUS(x) TORCH_CHECK(x.is_contiguous(), #x " must be contiguous")
+#define CHECK_INPUT(x) CHECK_CUDA(x); CHECK_CONTIGUOUS(x)
+
+torch::Tensor upfirdn2d(const torch::Tensor& input, const torch::Tensor& kernel,
+                        int up_x, int up_y, int down_x, int down_y,
+                        int pad_x0, int pad_x1, int pad_y0, int pad_y1) {
+    CHECK_CUDA(input);
+    CHECK_CUDA(kernel);
+
+    return upfirdn2d_op(input, kernel, up_x, up_y, down_x, down_y, pad_x0, pad_x1, pad_y0, pad_y1);
+}
+
+PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
+    m.def("upfirdn2d", &upfirdn2d, "upfirdn2d (CUDA)");
+}

op/upfirdn2d.py

@@ -0,0 +1,207 @@
+import os
+
+import torch
+from torch.nn import functional as F
+from torch.autograd import Function
+from torch.utils.cpp_extension import load
+
+
+module_path = os.path.dirname(__file__)
+
+cuda_available = torch.cuda.is_available()
+
+if cuda_available:
+    upfirdn2d_op = load(
+        "upfirdn2d",
+        sources=[
+            os.path.join(module_path, "upfirdn2d.cpp"),
+            os.path.join(module_path, "upfirdn2d_kernel.cu"),
+        ],
+    )
+else:
+    fused = None
+    print("upfirdn2d.py is running on cpu")
+
+
+class UpFirDn2dBackward(Function):
+    @staticmethod
+    def forward(
+        ctx, grad_output, kernel, grad_kernel, up, down, pad, g_pad, in_size, out_size
+    ):
+
+        up_x, up_y = up
+        down_x, down_y = down
+        g_pad_x0, g_pad_x1, g_pad_y0, g_pad_y1 = g_pad
+
+        grad_output = grad_output.reshape(-1, out_size[0], out_size[1], 1)
+
+        grad_input = upfirdn2d_op.upfirdn2d(
+            grad_output,
+            grad_kernel,
+            down_x,
+            down_y,
+            up_x,
+            up_y,
+            g_pad_x0,
+            g_pad_x1,
+            g_pad_y0,
+            g_pad_y1,
+        )
+        grad_input = grad_input.view(in_size[0], in_size[1], in_size[2], in_size[3])
+
+        ctx.save_for_backward(kernel)
+
+        pad_x0, pad_x1, pad_y0, pad_y1 = pad
+
+        ctx.up_x = up_x
+        ctx.up_y = up_y
+        ctx.down_x = down_x
+        ctx.down_y = down_y
+        ctx.pad_x0 = pad_x0
+        ctx.pad_x1 = pad_x1
+        ctx.pad_y0 = pad_y0
+        ctx.pad_y1 = pad_y1
+        ctx.in_size = in_size
+        ctx.out_size = out_size
+
+        return grad_input
+
+    @staticmethod
+    def backward(ctx, gradgrad_input):
+        kernel, = ctx.saved_tensors
+
+        gradgrad_input = gradgrad_input.reshape(-1, ctx.in_size[2], ctx.in_size[3], 1)
+
+        gradgrad_out = upfirdn2d_op.upfirdn2d(
+            gradgrad_input,
+            kernel,
+            ctx.up_x,
+            ctx.up_y,
+            ctx.down_x,
+            ctx.down_y,
+            ctx.pad_x0,
+            ctx.pad_x1,
+            ctx.pad_y0,
+            ctx.pad_y1,
+        )
+        # gradgrad_out = gradgrad_out.view(ctx.in_size[0], ctx.out_size[0], ctx.out_size[1], ctx.in_size[3])
+        gradgrad_out = gradgrad_out.view(
+            ctx.in_size[0], ctx.in_size[1], ctx.out_size[0], ctx.out_size[1]
+        )
+
+        return gradgrad_out, None, None, None, None, None, None, None, None
+
+
+class UpFirDn2d(Function):
+    @staticmethod
+    def forward(ctx, input, kernel, up, down, pad):
+        up_x, up_y = up
+        down_x, down_y = down
+        pad_x0, pad_x1, pad_y0, pad_y1 = pad
+
+        kernel_h, kernel_w = kernel.shape
+        batch, channel, in_h, in_w = input.shape
+        ctx.in_size = input.shape
+
+        input = input.reshape(-1, in_h, in_w, 1)
+
+        ctx.save_for_backward(kernel, torch.flip(kernel, [0, 1]))
+
+        out_h = (in_h * up_y + pad_y0 + pad_y1 - kernel_h) // down_y + 1
+        out_w = (in_w * up_x + pad_x0 + pad_x1 - kernel_w) // down_x + 1
+        ctx.out_size = (out_h, out_w)
+
+        ctx.up = (up_x, up_y)
+        ctx.down = (down_x, down_y)
+        ctx.pad = (pad_x0, pad_x1, pad_y0, pad_y1)
+
+        g_pad_x0 = kernel_w - pad_x0 - 1
+        g_pad_y0 = kernel_h - pad_y0 - 1
+        g_pad_x1 = in_w * up_x - out_w * down_x + pad_x0 - up_x + 1
+        g_pad_y1 = in_h * up_y - out_h * down_y + pad_y0 - up_y + 1
+
+        ctx.g_pad = (g_pad_x0, g_pad_x1, g_pad_y0, g_pad_y1)
+
+        out = upfirdn2d_op.upfirdn2d(
+            input, kernel, up_x, up_y, down_x, down_y, pad_x0, pad_x1, pad_y0, pad_y1
+        )
+        # out = out.view(major, out_h, out_w, minor)
+        out = out.view(-1, channel, out_h, out_w)
+
+        return out
+
+    @staticmethod
+    def backward(ctx, grad_output):
+        kernel, grad_kernel = ctx.saved_tensors
+
+        grad_input = UpFirDn2dBackward.apply(
+            grad_output,
+            kernel,
+            grad_kernel,
+            ctx.up,
+            ctx.down,
+            ctx.pad,
+            ctx.g_pad,
+            ctx.in_size,
+            ctx.out_size,
+        )
+
+        return grad_input, None, None, None, None
+
+
+def upfirdn2d(input, kernel, up=1, down=1, pad=(0, 0)):
+    if input.device.type == "cpu":
+        out = upfirdn2d_native(
+            input, kernel, up, up, down, down, pad[0], pad[1], pad[0], pad[1]
+        )
+
+    else:
+        out = UpFirDn2d.apply(
+            input, kernel, (up, up), (down, down), (pad[0], pad[1], pad[0], pad[1])
+        )
+
+    return out
+
+
+def upfirdn2d_native(
+    input, kernel, up_x, up_y, down_x, down_y, pad_x0, pad_x1, pad_y0, pad_y1
+):
+    _, channel, in_h, in_w = input.shape
+    input = input.reshape(-1, in_h, in_w, 1)
+
+    _, in_h, in_w, minor = input.shape
+    kernel_h, kernel_w = kernel.shape
+
+    out = input.view(-1, in_h, 1, in_w, 1, minor)
+    out = F.pad(out, [0, 0, 0, up_x - 1, 0, 0, 0, up_y - 1])
+    out = out.view(-1, in_h * up_y, in_w * up_x, minor)
+
+    out = F.pad(
+        out, [0, 0, max(pad_x0, 0), max(pad_x1, 0), max(pad_y0, 0), max(pad_y1, 0)]
+    )
+    out = out[
+        :,
+        max(-pad_y0, 0) : out.shape[1] - max(-pad_y1, 0),
+        max(-pad_x0, 0) : out.shape[2] - max(-pad_x1, 0),
+        :,
+    ]
+
+    out = out.permute(0, 3, 1, 2)
+    out = out.reshape(
+        [-1, 1, in_h * up_y + pad_y0 + pad_y1, in_w * up_x + pad_x0 + pad_x1]
+    )
+    w = torch.flip(kernel, [0, 1]).view(1, 1, kernel_h, kernel_w)
+    out = F.conv2d(out, w)
+    out = out.reshape(
+        -1,
+        minor,
+        in_h * up_y + pad_y0 + pad_y1 - kernel_h + 1,
+        in_w * up_x + pad_x0 + pad_x1 - kernel_w + 1,
+    )
+    out = out.permute(0, 2, 3, 1)
+    out = out[:, ::down_y, ::down_x, :]
+
+    out_h = (in_h * up_y + pad_y0 + pad_y1 - kernel_h) // down_y + 1
+    out_w = (in_w * up_x + pad_x0 + pad_x1 - kernel_w) // down_x + 1
+
+    return out.view(-1, channel, out_h, out_w)

op/upfirdn2d_kernel.cu

@@ -0,0 +1,369 @@
+// Copyright (c) 2019, NVIDIA Corporation. All rights reserved.
+//
+// This work is made available under the Nvidia Source Code License-NC.
+// To view a copy of this license, visit
+// https://nvlabs.github.io/stylegan2/license.html
+
+#include <torch/types.h>
+
+#include <ATen/ATen.h>
+#include <ATen/AccumulateType.h>
+#include <ATen/cuda/CUDAApplyUtils.cuh>
+#include <ATen/cuda/CUDAContext.h>
+
+#include <cuda.h>
+#include <cuda_runtime.h>
+
+static __host__ __device__ __forceinline__ int floor_div(int a, int b) {
+  int c = a / b;
+
+  if (c * b > a) {
+    c--;
+  }
+
+  return c;
+}
+
+struct UpFirDn2DKernelParams {
+  int up_x;
+  int up_y;
+  int down_x;
+  int down_y;
+  int pad_x0;
+  int pad_x1;
+  int pad_y0;
+  int pad_y1;
+
+  int major_dim;
+  int in_h;
+  int in_w;
+  int minor_dim;
+  int kernel_h;
+  int kernel_w;
+  int out_h;
+  int out_w;
+  int loop_major;
+  int loop_x;
+};
+
+template <typename scalar_t>
+__global__ void upfirdn2d_kernel_large(scalar_t *out, const scalar_t *input,
+                                       const scalar_t *kernel,
+                                       const UpFirDn2DKernelParams p) {
+  int minor_idx = blockIdx.x * blockDim.x + threadIdx.x;
+  int out_y = minor_idx / p.minor_dim;
+  minor_idx -= out_y * p.minor_dim;
+  int out_x_base = blockIdx.y * p.loop_x * blockDim.y + threadIdx.y;
+  int major_idx_base = blockIdx.z * p.loop_major;
+
+  if (out_x_base >= p.out_w || out_y >= p.out_h ||
+      major_idx_base >= p.major_dim) {
+    return;
+  }
+
+  int mid_y = out_y * p.down_y + p.up_y - 1 - p.pad_y0;
+  int in_y = min(max(floor_div(mid_y, p.up_y), 0), p.in_h);
+  int h = min(max(floor_div(mid_y + p.kernel_h, p.up_y), 0), p.in_h) - in_y;
+  int kernel_y = mid_y + p.kernel_h - (in_y + 1) * p.up_y;
+
+  for (int loop_major = 0, major_idx = major_idx_base;
+       loop_major < p.loop_major && major_idx < p.major_dim;
+       loop_major++, major_idx++) {
+    for (int loop_x = 0, out_x = out_x_base;
+         loop_x < p.loop_x && out_x < p.out_w; loop_x++, out_x += blockDim.y) {
+      int mid_x = out_x * p.down_x + p.up_x - 1 - p.pad_x0;
+      int in_x = min(max(floor_div(mid_x, p.up_x), 0), p.in_w);
+      int w = min(max(floor_div(mid_x + p.kernel_w, p.up_x), 0), p.in_w) - in_x;
+      int kernel_x = mid_x + p.kernel_w - (in_x + 1) * p.up_x;
+
+      const scalar_t *x_p =
+          &input[((major_idx * p.in_h + in_y) * p.in_w + in_x) * p.minor_dim +
+                 minor_idx];
+      const scalar_t *k_p = &kernel[kernel_y * p.kernel_w + kernel_x];
+      int x_px = p.minor_dim;
+      int k_px = -p.up_x;
+      int x_py = p.in_w * p.minor_dim;
+      int k_py = -p.up_y * p.kernel_w;
+
+      scalar_t v = 0.0f;
+
+      for (int y = 0; y < h; y++) {
+        for (int x = 0; x < w; x++) {
+          v += static_cast<scalar_t>(*x_p) * static_cast<scalar_t>(*k_p);
+          x_p += x_px;
+          k_p += k_px;
+        }
+
+        x_p += x_py - w * x_px;
+        k_p += k_py - w * k_px;
+      }
+
+      out[((major_idx * p.out_h + out_y) * p.out_w + out_x) * p.minor_dim +
+          minor_idx] = v;
+    }
+  }
+}
+
+template <typename scalar_t, int up_x, int up_y, int down_x, int down_y,
+          int kernel_h, int kernel_w, int tile_out_h, int tile_out_w>
+__global__ void upfirdn2d_kernel(scalar_t *out, const scalar_t *input,
+                                 const scalar_t *kernel,
+                                 const UpFirDn2DKernelParams p) {
+  const int tile_in_h = ((tile_out_h - 1) * down_y + kernel_h - 1) / up_y + 1;
+  const int tile_in_w = ((tile_out_w - 1) * down_x + kernel_w - 1) / up_x + 1;
+
+  __shared__ volatile float sk[kernel_h][kernel_w];
+  __shared__ volatile float sx[tile_in_h][tile_in_w];
+
+  int minor_idx = blockIdx.x;
+  int tile_out_y = minor_idx / p.minor_dim;
+  minor_idx -= tile_out_y * p.minor_dim;
+  tile_out_y *= tile_out_h;
+  int tile_out_x_base = blockIdx.y * p.loop_x * tile_out_w;
+  int major_idx_base = blockIdx.z * p.loop_major;
+
+  if (tile_out_x_base >= p.out_w | tile_out_y >= p.out_h |
+      major_idx_base >= p.major_dim) {
+    return;
+  }
+
+  for (int tap_idx = threadIdx.x; tap_idx < kernel_h * kernel_w;
+       tap_idx += blockDim.x) {
+    int ky = tap_idx / kernel_w;
+    int kx = tap_idx - ky * kernel_w;
+    scalar_t v = 0.0;
+
+    if (kx < p.kernel_w & ky < p.kernel_h) {
+      v = kernel[(p.kernel_h - 1 - ky) * p.kernel_w + (p.kernel_w - 1 - kx)];
+    }
+
+    sk[ky][kx] = v;
+  }
+
+  for (int loop_major = 0, major_idx = major_idx_base;
+       loop_major < p.loop_major & major_idx < p.major_dim;
+       loop_major++, major_idx++) {
+    for (int loop_x = 0, tile_out_x = tile_out_x_base;
+         loop_x < p.loop_x & tile_out_x < p.out_w;
+         loop_x++, tile_out_x += tile_out_w) {
+      int tile_mid_x = tile_out_x * down_x + up_x - 1 - p.pad_x0;
+      int tile_mid_y = tile_out_y * down_y + up_y - 1 - p.pad_y0;
+      int tile_in_x = floor_div(tile_mid_x, up_x);
+      int tile_in_y = floor_div(tile_mid_y, up_y);
+
+      __syncthreads();
+
+      for (int in_idx = threadIdx.x; in_idx < tile_in_h * tile_in_w;
+           in_idx += blockDim.x) {
+        int rel_in_y = in_idx / tile_in_w;
+        int rel_in_x = in_idx - rel_in_y * tile_in_w;
+        int in_x = rel_in_x + tile_in_x;
+        int in_y = rel_in_y + tile_in_y;
+
+        scalar_t v = 0.0;
+
+        if (in_x >= 0 & in_y >= 0 & in_x < p.in_w & in_y < p.in_h) {
+          v = input[((major_idx * p.in_h + in_y) * p.in_w + in_x) *
+                        p.minor_dim +
+                    minor_idx];
+        }
+
+        sx[rel_in_y][rel_in_x] = v;
+      }
+
+      __syncthreads();
+      for (int out_idx = threadIdx.x; out_idx < tile_out_h * tile_out_w;
+           out_idx += blockDim.x) {
+        int rel_out_y = out_idx / tile_out_w;
+        int rel_out_x = out_idx - rel_out_y * tile_out_w;
+        int out_x = rel_out_x + tile_out_x;
+        int out_y = rel_out_y + tile_out_y;
+
+        int mid_x = tile_mid_x + rel_out_x * down_x;
+        int mid_y = tile_mid_y + rel_out_y * down_y;
+        int in_x = floor_div(mid_x, up_x);
+        int in_y = floor_div(mid_y, up_y);
+        int rel_in_x = in_x - tile_in_x;
+        int rel_in_y = in_y - tile_in_y;
+        int kernel_x = (in_x + 1) * up_x - mid_x - 1;
+        int kernel_y = (in_y + 1) * up_y - mid_y - 1;
+
+        scalar_t v = 0.0;
+
+#pragma unroll
+        for (int y = 0; y < kernel_h / up_y; y++)
+#pragma unroll
+          for (int x = 0; x < kernel_w / up_x; x++)
+            v += sx[rel_in_y + y][rel_in_x + x] *
+                 sk[kernel_y + y * up_y][kernel_x + x * up_x];
+
+        if (out_x < p.out_w & out_y < p.out_h) {
+          out[((major_idx * p.out_h + out_y) * p.out_w + out_x) * p.minor_dim +
+              minor_idx] = v;
+        }
+      }
+    }
+  }
+}
+
+torch::Tensor upfirdn2d_op(const torch::Tensor &input,
+                           const torch::Tensor &kernel, int up_x, int up_y,
+                           int down_x, int down_y, int pad_x0, int pad_x1,
+                           int pad_y0, int pad_y1) {
+  int curDevice = -1;
+  cudaGetDevice(&curDevice);
+  cudaStream_t stream = at::cuda::getCurrentCUDAStream(curDevice);
+
+  UpFirDn2DKernelParams p;
+
+  auto x = input.contiguous();
+  auto k = kernel.contiguous();
+
+  p.major_dim = x.size(0);
+  p.in_h = x.size(1);
+  p.in_w = x.size(2);
+  p.minor_dim = x.size(3);
+  p.kernel_h = k.size(0);
+  p.kernel_w = k.size(1);
+  p.up_x = up_x;
+  p.up_y = up_y;
+  p.down_x = down_x;
+  p.down_y = down_y;
+  p.pad_x0 = pad_x0;
+  p.pad_x1 = pad_x1;
+  p.pad_y0 = pad_y0;
+  p.pad_y1 = pad_y1;
+
+  p.out_h = (p.in_h * p.up_y + p.pad_y0 + p.pad_y1 - p.kernel_h + p.down_y) /
+            p.down_y;
+  p.out_w = (p.in_w * p.up_x + p.pad_x0 + p.pad_x1 - p.kernel_w + p.down_x) /
+            p.down_x;
+
+  auto out =
+      at::empty({p.major_dim, p.out_h, p.out_w, p.minor_dim}, x.options());
+
+  int mode = -1;
+
+  int tile_out_h = -1;
+  int tile_out_w = -1;
+
+  if (p.up_x == 1 && p.up_y == 1 && p.down_x == 1 && p.down_y == 1 &&
+      p.kernel_h <= 4 && p.kernel_w <= 4) {
+    mode = 1;
+    tile_out_h = 16;
+    tile_out_w = 64;
+  }
+
+  if (p.up_x == 1 && p.up_y == 1 && p.down_x == 1 && p.down_y == 1 &&
+      p.kernel_h <= 3 && p.kernel_w <= 3) {
+    mode = 2;
+    tile_out_h = 16;
+    tile_out_w = 64;
+  }
+
+  if (p.up_x == 2 && p.up_y == 2 && p.down_x == 1 && p.down_y == 1 &&
+      p.kernel_h <= 4 && p.kernel_w <= 4) {
+    mode = 3;
+    tile_out_h = 16;
+    tile_out_w = 64;
+  }
+
+  if (p.up_x == 2 && p.up_y == 2 && p.down_x == 1 && p.down_y == 1 &&
+      p.kernel_h <= 2 && p.kernel_w <= 2) {
+    mode = 4;
+    tile_out_h = 16;
+    tile_out_w = 64;
+  }
+
+  if (p.up_x == 1 && p.up_y == 1 && p.down_x == 2 && p.down_y == 2 &&
+      p.kernel_h <= 4 && p.kernel_w <= 4) {
+    mode = 5;
+    tile_out_h = 8;
+    tile_out_w = 32;
+  }
+
+  if (p.up_x == 1 && p.up_y == 1 && p.down_x == 2 && p.down_y == 2 &&
+      p.kernel_h <= 2 && p.kernel_w <= 2) {
+    mode = 6;
+    tile_out_h = 8;
+    tile_out_w = 32;
+  }
+
+  dim3 block_size;
+  dim3 grid_size;
+
+  if (tile_out_h > 0 && tile_out_w > 0) {
+    p.loop_major = (p.major_dim - 1) / 16384 + 1;
+    p.loop_x = 1;
+    block_size = dim3(32 * 8, 1, 1);
+    grid_size = dim3(((p.out_h - 1) / tile_out_h + 1) * p.minor_dim,
+                     (p.out_w - 1) / (p.loop_x * tile_out_w) + 1,
+                     (p.major_dim - 1) / p.loop_major + 1);
+  } else {
+    p.loop_major = (p.major_dim - 1) / 16384 + 1;
+    p.loop_x = 4;
+    block_size = dim3(4, 32, 1);
+    grid_size = dim3((p.out_h * p.minor_dim - 1) / block_size.x + 1,
+                     (p.out_w - 1) / (p.loop_x * block_size.y) + 1,
+                     (p.major_dim - 1) / p.loop_major + 1);
+  }
+
+  AT_DISPATCH_FLOATING_TYPES_AND_HALF(x.scalar_type(), "upfirdn2d_cuda", [&] {
+    switch (mode) {
+    case 1:
+      upfirdn2d_kernel<scalar_t, 1, 1, 1, 1, 4, 4, 16, 64>
+          <<<grid_size, block_size, 0, stream>>>(out.data_ptr<scalar_t>(),
+                                                 x.data_ptr<scalar_t>(),
+                                                 k.data_ptr<scalar_t>(), p);
+
+      break;
+
+    case 2:
+      upfirdn2d_kernel<scalar_t, 1, 1, 1, 1, 3, 3, 16, 64>
+          <<<grid_size, block_size, 0, stream>>>(out.data_ptr<scalar_t>(),
+                                                 x.data_ptr<scalar_t>(),
+                                                 k.data_ptr<scalar_t>(), p);
+
+      break;
+
+    case 3:
+      upfirdn2d_kernel<scalar_t, 2, 2, 1, 1, 4, 4, 16, 64>
+          <<<grid_size, block_size, 0, stream>>>(out.data_ptr<scalar_t>(),
+                                                 x.data_ptr<scalar_t>(),
+                                                 k.data_ptr<scalar_t>(), p);
+
+      break;
+
+    case 4:
+      upfirdn2d_kernel<scalar_t, 2, 2, 1, 1, 2, 2, 16, 64>
+          <<<grid_size, block_size, 0, stream>>>(out.data_ptr<scalar_t>(),
+                                                 x.data_ptr<scalar_t>(),
+                                                 k.data_ptr<scalar_t>(), p);
+
+      break;
+
+    case 5:
+      upfirdn2d_kernel<scalar_t, 1, 1, 2, 2, 4, 4, 8, 32>
+          <<<grid_size, block_size, 0, stream>>>(out.data_ptr<scalar_t>(),
+                                                 x.data_ptr<scalar_t>(),
+                                                 k.data_ptr<scalar_t>(), p);
+
+      break;
+
+    case 6:
+      upfirdn2d_kernel<scalar_t, 1, 1, 2, 2, 4, 4, 8, 32>
+          <<<grid_size, block_size, 0, stream>>>(out.data_ptr<scalar_t>(),
+                                                 x.data_ptr<scalar_t>(),
+                                                 k.data_ptr<scalar_t>(), p);
+
+      break;
+
+    default:
+      upfirdn2d_kernel_large<scalar_t><<<grid_size, block_size, 0, stream>>>(
+          out.data_ptr<scalar_t>(), x.data_ptr<scalar_t>(),
+          k.data_ptr<scalar_t>(), p);
+    }
+  });
+
+  return out;
+}

psp_encoder/helpers.py

@@ -0,0 +1,119 @@
+from collections import namedtuple
+import torch
+from torch.nn import Conv2d, BatchNorm2d, PReLU, ReLU, Sigmoid, MaxPool2d, AdaptiveAvgPool2d, Sequential, Module
+
+"""
+ArcFace implementation from [TreB1eN](https://github.com/TreB1eN/InsightFace_Pytorch)
+"""
+
+
+class Flatten(Module):
+	def forward(self, input):
+		return input.view(input.size(0), -1)
+
+
+def l2_norm(input, axis=1):
+	norm = torch.norm(input, 2, axis, True)
+	output = torch.div(input, norm)
+	return output
+
+
+class Bottleneck(namedtuple('Block', ['in_channel', 'depth', 'stride'])):
+	""" A named tuple describing a ResNet block. """
+
+
+def get_block(in_channel, depth, num_units, stride=2):
+	return [Bottleneck(in_channel, depth, stride)] + [Bottleneck(depth, depth, 1) for i in range(num_units - 1)]
+
+
+def get_blocks(num_layers):
+	if num_layers == 50:
+		blocks = [
+			get_block(in_channel=64, depth=64, num_units=3),
+			get_block(in_channel=64, depth=128, num_units=4),
+			get_block(in_channel=128, depth=256, num_units=14),
+			get_block(in_channel=256, depth=512, num_units=3)
+		]
+	elif num_layers == 100:
+		blocks = [
+			get_block(in_channel=64, depth=64, num_units=3),
+			get_block(in_channel=64, depth=128, num_units=13),
+			get_block(in_channel=128, depth=256, num_units=30),
+			get_block(in_channel=256, depth=512, num_units=3)
+		]
+	elif num_layers == 152:
+		blocks = [
+			get_block(in_channel=64, depth=64, num_units=3),
+			get_block(in_channel=64, depth=128, num_units=8),
+			get_block(in_channel=128, depth=256, num_units=36),
+			get_block(in_channel=256, depth=512, num_units=3)
+		]
+	else:
+		raise ValueError("Invalid number of layers: {}. Must be one of [50, 100, 152]".format(num_layers))
+	return blocks
+
+
+class SEModule(Module):
+	def __init__(self, channels, reduction):
+		super(SEModule, self).__init__()
+		self.avg_pool = AdaptiveAvgPool2d(1)
+		self.fc1 = Conv2d(channels, channels // reduction, kernel_size=1, padding=0, bias=False)
+		self.relu = ReLU(inplace=True)
+		self.fc2 = Conv2d(channels // reduction, channels, kernel_size=1, padding=0, bias=False)
+		self.sigmoid = Sigmoid()
+
+	def forward(self, x):
+		module_input = x
+		x = self.avg_pool(x)
+		x = self.fc1(x)
+		x = self.relu(x)
+		x = self.fc2(x)
+		x = self.sigmoid(x)
+		return module_input * x
+
+
+class bottleneck_IR(Module):
+	def __init__(self, in_channel, depth, stride):
+		super(bottleneck_IR, self).__init__()
+		if in_channel == depth:
+			self.shortcut_layer = MaxPool2d(1, stride)
+		else:
+			self.shortcut_layer = Sequential(
+				Conv2d(in_channel, depth, (1, 1), stride, bias=False),
+				BatchNorm2d(depth)
+			)
+		self.res_layer = Sequential(
+			BatchNorm2d(in_channel),
+			Conv2d(in_channel, depth, (3, 3), (1, 1), 1, bias=False), PReLU(depth),
+			Conv2d(depth, depth, (3, 3), stride, 1, bias=False), BatchNorm2d(depth)
+		)
+
+	def forward(self, x):
+		shortcut = self.shortcut_layer(x)
+		res = self.res_layer(x)
+		return res + shortcut
+
+
+class bottleneck_IR_SE(Module):
+	def __init__(self, in_channel, depth, stride):
+		super(bottleneck_IR_SE, self).__init__()
+		if in_channel == depth:
+			self.shortcut_layer = MaxPool2d(1, stride)
+		else:
+			self.shortcut_layer = Sequential(
+				Conv2d(in_channel, depth, (1, 1), stride, bias=False),
+				BatchNorm2d(depth)
+			)
+		self.res_layer = Sequential(
+			BatchNorm2d(in_channel),
+			Conv2d(in_channel, depth, (3, 3), (1, 1), 1, bias=False),
+			PReLU(depth),
+			Conv2d(depth, depth, (3, 3), stride, 1, bias=False),
+			BatchNorm2d(depth),
+			SEModule(depth, 16)
+		)
+
+	def forward(self, x):
+		shortcut = self.shortcut_layer(x)
+		res = self.res_layer(x)
+		return res + shortcut

psp_encoder/psp_encoders.py

@@ -0,0 +1,153 @@
+import numpy as np
+import torch
+import torch.nn.functional as F
+from torch import nn
+from torch.nn import Conv2d, BatchNorm2d, PReLU, Sequential, Module
+import math
+
+from .helpers import get_blocks, bottleneck_IR, bottleneck_IR_SE
+
+import sys, os
+sys.path.append(os.path.dirname(__file__) + os.sep + '../')
+from model import EqualLinear
+
+
+"""
+Modified from [pSp](https://github.com/eladrich/pixel2style2pixel)
+"""
+
+
+class GradualStyleBlock(Module):
+    def __init__(self, in_c, out_c, spatial):
+        super(GradualStyleBlock, self).__init__()
+        self.out_c = out_c
+        self.spatial = spatial
+        num_pools = int(np.log2(spatial))
+        modules = []
+        modules += [Conv2d(in_c, out_c, kernel_size=3, stride=2, padding=1),
+                    nn.LeakyReLU()]
+        for i in range(num_pools - 1):
+            modules += [
+                Conv2d(out_c, out_c, kernel_size=3, stride=2, padding=1),
+                nn.LeakyReLU()
+            ]
+        self.convs = nn.Sequential(*modules)
+        self.linear = EqualLinear(out_c, out_c, lr_mul=1)
+
+    def forward(self, x):
+        x = self.convs(x)
+        x = x.view(-1, self.out_c)
+        x = self.linear(x)
+        return x
+
+
+class GradualStyleEncoder(Module):
+    def __init__(self, num_layers, mode='ir', n_styles=18):
+        super(GradualStyleEncoder, self).__init__()
+        assert num_layers in [50, 100, 152], 'num_layers should be 50,100, or 152'
+        assert mode in ['ir', 'ir_se'], 'mode should be ir or ir_se'
+        blocks = get_blocks(num_layers)
+        if mode == 'ir':
+            unit_module = bottleneck_IR
+        elif mode == 'ir_se':
+            unit_module = bottleneck_IR_SE
+        self.input_layer = Sequential(Conv2d(3, 64, (3, 3), 1, 1, bias=False),
+                                      BatchNorm2d(64),
+                                      PReLU(64))
+        modules = []
+        for block in blocks:
+            for bottleneck in block:
+                modules.append(unit_module(bottleneck.in_channel,
+                                           bottleneck.depth,
+                                           bottleneck.stride))
+        self.body = Sequential(*modules)
+
+        self.styles = nn.ModuleList()
+        self.style_count = n_styles  # opts.n_styles
+        self.coarse_ind = 3
+        self.middle_ind = 7
+        for i in range(self.style_count):
+            if i < self.coarse_ind:
+                style = GradualStyleBlock(512, 512, 16)
+            elif i < self.middle_ind:
+                style = GradualStyleBlock(512, 512, 32)
+            else:
+                style = GradualStyleBlock(512, 512, 64)
+            self.styles.append(style)
+        self.latlayer1 = nn.Conv2d(256, 512, kernel_size=1, stride=1, padding=0)
+        self.latlayer2 = nn.Conv2d(128, 512, kernel_size=1, stride=1, padding=0)
+
+    def _upsample_add(self, x, y):
+        '''Upsample and add two feature maps.
+        Args:
+          x: (Variable) top feature map to be upsampled.
+          y: (Variable) lateral feature map.
+        Returns:
+          (Variable) added feature map.
+        Note in PyTorch, when input size is odd, the upsampled feature map
+        with `F.upsample(..., scale_factor=2, mode='nearest')`
+        maybe not equal to the lateral feature map size.
+        e.g.
+        original input size: [N,_,15,15] ->
+        conv2d feature map size: [N,_,8,8] ->
+        upsampled feature map size: [N,_,16,16]
+        So we choose bilinear upsample which supports arbitrary output sizes.
+        '''
+        _, _, H, W = y.size()
+        return F.interpolate(x, size=(H, W), mode='bilinear', align_corners=True) + y
+
+    def forward(self, x):
+        x = self.input_layer(x)
+
+        latents = []
+        modulelist = list(self.body._modules.values())
+        for i, l in enumerate(modulelist):
+            x = l(x)
+            if i == 6:
+                c1 = x
+            elif i == 20:
+                c2 = x
+            elif i == 23:
+                c3 = x
+
+        for j in range(self.coarse_ind):
+            latents.append(self.styles[j](c3))
+
+        p2 = self._upsample_add(c3, self.latlayer1(c2))
+        for j in range(self.coarse_ind, self.middle_ind):
+            latents.append(self.styles[j](p2))
+
+        p1 = self._upsample_add(p2, self.latlayer2(c1))
+        for j in range(self.middle_ind, self.style_count):
+            latents.append(self.styles[j](p1))
+
+        out = torch.stack(latents, dim=1)
+        return out
+
+
+def get_keys(d, name):
+    if 'state_dict' in d:
+        d = d['state_dict']
+    d_filt = {k[len(name) + 1:]: v for k, v in d.items() if k[:len(name)] == name}
+    return d_filt
+
+
+class PSPEncoder(Module):
+    def __init__(self, encoder_ckpt_path, output_size=1024):
+        super(PSPEncoder, self).__init__()
+        n_styles = int(math.log(output_size, 2)) * 2 - 2
+        self.encoder = GradualStyleEncoder(50, 'ir_se', n_styles)
+
+        print('Loading psp encoders weights from irse50!')
+        encoder_ckpt = torch.load(encoder_ckpt_path, map_location='cpu')
+        self.encoder.load_state_dict(get_keys(encoder_ckpt, 'encoder'), strict=True)
+        self.latent_avg = encoder_ckpt['latent_avg'].cuda()
+
+        self.face_pool = torch.nn.AdaptiveAvgPool2d((256, 256))
+
+    def forward(self, x):
+        x = self.face_pool(x)
+        codes = self.encoder(x)
+        codes = codes + self.latent_avg.repeat(codes.shape[0], 1, 1)
+        return codes
+

style_transfer_folder.py

@@ -0,0 +1,92 @@
+import argparse
+import os
+
+import cv2
+import numpy as np
+import torch
+
+from model import Generator
+from psp_encoder.psp_encoders import PSPEncoder
+from utils import ten2cv, cv2ten
+import glob
+import random
+
+seed = 0
+
+random.seed(seed)
+np.random.seed(seed)
+torch.manual_seed(seed)
+torch.cuda.manual_seed_all(seed)
+
+
+if __name__ == '__main__':
+    device = 'cuda'
+
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument('--size', type=int, default=1024)
+
+    parser.add_argument('--ckpt', type=str, default='', help='path to BlendGAN checkpoint')
+    parser.add_argument('--psp_encoder_ckpt', type=str, default='', help='path to psp_encoder checkpoint')
+
+    parser.add_argument('--style_img_path', type=str, default=None, help='path to style image')
+    parser.add_argument('--input_img_path', type=str, default=None, help='path to input image')
+    parser.add_argument('--add_weight_index', type=int, default=6)
+
+    parser.add_argument('--channel_multiplier', type=int, default=2)
+    parser.add_argument('--outdir', type=str, default="")
+
+    args = parser.parse_args()
+
+    outdir = args.outdir
+    if not os.path.exists(outdir):
+        os.makedirs(outdir, exist_ok=True)
+
+    args.latent = 512
+    args.n_mlp = 8
+
+    checkpoint = torch.load(args.ckpt)
+    model_dict = checkpoint['g_ema']
+    print('ckpt: ', args.ckpt)
+
+    g_ema = Generator(
+        args.size, args.latent, args.n_mlp, channel_multiplier=args.channel_multiplier
+    ).to(device)
+    g_ema.load_state_dict(model_dict)
+    g_ema.eval()
+
+    psp_encoder = PSPEncoder(args.psp_encoder_ckpt, output_size=args.size).to(device)
+    psp_encoder.eval()
+
+    input_img_paths = sorted(glob.glob(os.path.join(args.input_img_path, '*.*')))
+    style_img_paths = sorted(glob.glob(os.path.join(args.style_img_path, '*.*')))[:]
+
+    num = 0
+
+    for input_img_path in input_img_paths:
+        print(num)
+        num += 1
+
+        name_in = os.path.splitext(os.path.basename(input_img_path))[0]
+        img_in = cv2.imread(input_img_path, 1)
+        img_in_ten = cv2ten(img_in, device)
+        img_in = cv2.resize(img_in, (args.size, args.size))
+
+        for style_img_path in style_img_paths:
+            name_style = os.path.splitext(os.path.basename(style_img_path))[0]
+            img_style = cv2.imread(style_img_path, 1)
+            img_style_ten = cv2ten(img_style, device)
+            img_style = cv2.resize(img_style, (args.size, args.size))
+
+            with torch.no_grad():
+                sample_style = g_ema.get_z_embed(img_style_ten)
+                sample_in = psp_encoder(img_in_ten)
+                img_out_ten, _ = g_ema([sample_in], z_embed=sample_style, add_weight_index=args.add_weight_index,
+                                       input_is_latent=True, return_latents=False, randomize_noise=False)
+                img_out = ten2cv(img_out_ten)
+            out = np.concatenate([img_in, img_style, img_out], axis=1)
+            # out = img_out
+            cv2.imwrite(f'{args.outdir}/{name_in}_v_{name_style}.jpg', out)
+
+    print('Done!')
+

utils.py

@@ -0,0 +1,15 @@
+import torch
+
+
+def cv2ten(img, device):
+    img = (img[:, :, ::-1].transpose(2, 0, 1) / 255. - 0.5) / 0.5
+    img_ten = torch.from_numpy(img).float().unsqueeze(0).to(device)
+    return img_ten
+
+
+def ten2cv(img_ten, bgr=True):
+    img = img_ten.squeeze(0).mul_(0.5).add_(0.5).mul_(255).clamp_(0, 255).permute(1, 2, 0).to('cpu', torch.uint8).numpy()
+    if bgr:
+        img = img[:, :, ::-1]
+    return img
+