DragGAN_Streamlit / draggan.py
Evan Davis
Add files from GH
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import os
import sys
import time
from typing import List, Optional, Tuple
import math
import numpy as np
import PIL
import torch
import streamlit as st
stylegan2_dir = os.path.abspath("stylegan2")
sys.path.insert(0, stylegan2_dir)
import dnnlib
import legacy
import utils
@st.cache_resource
def load_model(
network_pkl: str = "https://nvlabs-fi-cdn.nvidia.com/stylegan2-ada-pytorch/pretrained/afhqdog.pkl",
device: torch.device = torch.device("cuda"),
fp16: bool = True,
) -> torch.nn.Module:
"""
Loads a pretrained StyleGAN2-ADA generator network from a pickle file.
Args:
network_pkl (str): The URL or local path to the network pickle file.
device (torch.device): The device to use for the computation.
fp16 (bool): Whether to use half-precision floating point format for the network weights.
Returns:
The pretrained generator network.
"""
print('Loading networks from "%s"...' % network_pkl)
with dnnlib.util.open_url(network_pkl) as f:
chkpt = legacy.load_network_pkl(f, force_fp16=fp16)
G = chkpt["G_ema"].to(device).eval()
for param in G.parameters():
param.requires_grad_(False)
# Create a new attribute called "activations" for the Generator class
# This will be a list of activations from each layer
G.__setattr__("activations", None)
# Forward hook to collect features
def hook(module, input, output):
G.activations = output
# Apply the hook to the 7th layer (256x256)
for i, (name, module) in enumerate(G.synthesis.named_children()):
if i == 6:
print("Registering hook for:", name)
module.register_forward_hook(hook)
return G
@st.cache_data()
def generate_W(
_G: torch.nn.Module,
seed: int = 0,
network_pkl: Optional[str] = None,
truncation_psi: float = 1.0,
truncation_cutoff: Optional[int] = None,
device: torch.device = torch.device("cuda"),
) -> np.ndarray:
"""
Generates a latent code tensor in W+ space from a pretrained StyleGAN2-ADA generator network.
Args:
_G (torch.nn.Module): The generator network, with underscore to avoid streamlit cache error
seed (int): The random seed to use for generating the latent code.
network_pkl (Optional[str]): The path to the network pickle file. If None, the default network will be used.
truncation_psi (float): The truncation psi value to use for the mapping network.
truncation_cutoff (Optional[int]): The number of layers to use for the truncation trick. If None, all layers will be used.
device (torch.device): The device to use for the computation.
Returns:
The W+ latent as a numpy array of shape [1, num_layers, 512].
"""
G = _G
torch.manual_seed(seed)
z = torch.randn(1, G.z_dim).to(device)
num_layers = G.synthesis.num_ws
if truncation_cutoff == -1:
truncation_cutoff = None
elif truncation_cutoff is not None:
truncation_cutoff = min(num_layers, truncation_cutoff)
W = G.mapping(
z,
None,
truncation_psi=truncation_psi,
truncation_cutoff=truncation_cutoff,
)
return W.cpu().numpy()
def forward_G(
G: torch.nn.Module,
W: torch.Tensor,
device: torch.device,
) -> Tuple[torch.Tensor, torch.Tensor]:
"""
Forward pass through the generator network.
Args:
G (torch.nn.Module): The generator network.
W (torch.Tensor): The latent code tensor of shape [batch_size, latent_dim, 512].
device (torch.device): The device to use for the computation.
Returns:
A tuple containing the generated image tensor of shape [batch_size, 3, height, width]
and the feature maps tensor of shape [batch_size, num_channels, height, width].
"""
if not isinstance(W, torch.Tensor):
W = torch.from_numpy(W).to(device)
img = G.synthesis(W, noise_mode="const", force_fp32=True)
return img, G.activations[0]
@st.cache_data()
def generate_image(
W,
_G: Optional[torch.nn.Module] = None,
network_pkl: Optional[str] = None,
class_idx=None,
device=torch.device("cuda"),
) -> Tuple[PIL.Image.Image, torch.Tensor]:
"""
Generates an image using a pretrained generator network.
Args:
W (torch.Tensor): A tensor of latent codes of shape [batch_size, latent_dim, 512].
_G (Optional[torch.nn.Module]): The generator network. If None, the network will be loaded from `network_pkl`.
network_pkl (Optional[str]): The path to the network pickle file. If None, the default network will be used.
class_idx (Optional[int]): The class index to use for conditional generation. If None, unconditional generation will be used.
device (str): The device to use for the computation.
Returns:
A tuple containing the generated image as a PIL Image object and the feature maps tensor of shape [batch_size, num_channels, height, width].
"""
if _G is None:
assert network_pkl is not None
_G = load_model(network_pkl, device)
G = _G
# Labels.
label = torch.zeros([1, G.c_dim], device=device)
if G.c_dim != 0:
if class_idx is None:
raise Exception(
"Must specify class label with --class when using a conditional network"
)
label[:, class_idx] = 1
else:
if class_idx is not None:
print("warn: --class=lbl ignored when running on an unconditional network")
## Generate image
img, features = forward_G(G, W, device)
img = utils.tensor_to_PIL(img)
return img, features
def optimize(
W: np.ndarray,
G: torch.nn.Module,
handle_points: List[Tuple[int, int]],
target_points: List[Tuple[int, int]],
r1: int = 3,
r2: int = 12,
tolerance: int = 2,
max_iter: int = 200,
lr: float = 0.1,
multiplier: float = 1.0,
lambda_: float = 0.1,
device: torch.device = torch.device("cuda"),
empty=None,
display_every: int = 10,
target_resolution: int = 512,
) -> np.ndarray:
"""
Optimizes the latent code tensor W to generate an image that matches the target points.
Args:
W (np.ndarray): The initial latent code tensor of shape [1, num_layers, 512].
G (torch.nn.Module): The generator network.
handle_points (List[Tuple[int, int]]): The initial handle points as a list of (x, y) tuples.
target_points (List[Tuple[int, int]]): The target points as a list of (x, y) tuples.
r1 (int): The radius of the motion supervision loss.
r2 (int): The radius of the point tracking.
d (int): The tolerance for the handle points to reach the target points.
max_iter (int): The maximum number of optimization iterations.
lr (float): The learning rate for the optimizer.
multiplier (float): The speed multiplier for the motion supervision loss.
lambda_ (float): The weight of the motion supervision loss.
device (torch.device): The device to use for the computation.
empty: The st.empty object to display the intermediate images.
display_every (int): The number of iterations between displaying intermediate images.
target_resolution (int): The target resolution for the generated image.
Returns:
The optimized latent code tensor W as a numpy array of shape [1, num_layers, 512].
"""
img, F0 = forward_G(G, W, device)
empty.image(
utils.tensor_to_PIL(img), caption="Initial image", width=target_resolution
)
F0_resized = torch.nn.functional.interpolate(
F0,
size=(target_resolution, target_resolution),
mode="bilinear",
align_corners=True,
).detach()
# Convert handle/target points to tensors and reorder to [y, x]
handle_points: torch.tensor = (
torch.tensor(handle_points, device=device).flip(-1).float()
)
handle_points_0 = handle_points.clone()
target_points: torch.tensor = (
torch.tensor(target_points, device=device).flip(-1).float()
)
W = torch.from_numpy(W).to(device).float()
W.requires_grad_(False)
# Only optimize the first 6 layers of W
W_layers_to_optimize = W[:, :6].clone()
W_layers_to_optimize.requires_grad_(True)
optimizer = torch.optim.Adam([W_layers_to_optimize], lr=lr)
for i in range(max_iter):
start = time.perf_counter()
# # Check if the handle points have reached the target points
if torch.allclose(handle_points, target_points, atol=tolerance):
break
optimizer.zero_grad()
# Detach only the unoptimized layers
W_combined = torch.cat([W_layers_to_optimize, W[:, 6:].detach()], dim=1)
# Run the generator to get the image and feature maps
img, F = forward_G(G, W_combined, device)
## Bilinear interpolate F to be same size as img
F_resized = torch.nn.functional.interpolate(
F,
size=(target_resolution, target_resolution),
mode="bilinear",
align_corners=True,
)
# Compute the motion supervision loss
loss, all_shifted_coordinates = motion_supervision(
F_resized,
F0_resized,
handle_points,
target_points,
r1,
lambda_,
device,
multiplier=multiplier,
)
# Backpropagate the loss and update the latent code
loss.backward()
# # Clip gradients if their norm exceeds max_grad_norm
# torch.nn.utils.clip_grad_norm_(W_layers_to_optimize, 1.0)
# # Compute the L2 regularization term
# l2_regularization = 100 * torch.norm(W_layers_to_optimize - W[:, :6]) ** 2
# print(l2_regularization.item())
# # Add the regularization term to the loss
# loss += l2_regularization
optimizer.step()
print(
f"{i}\tLoss: {loss.item():0.2f}\tTime: {(time.perf_counter() - start) * 1000:.0f}ms"
)
if i % display_every == 0 or i == max_iter - 1:
# Draw d_i intermediate target as orange ellipse
img = utils.tensor_to_PIL(img)
if img.size[0] != target_resolution:
img = img.resize((target_resolution, target_resolution))
utils.draw_handle_target_points(img, handle_points.flip(-1).cpu().long().numpy().tolist(), target_points.flip(-1).cpu().long().numpy().tolist())
# draw = PIL.ImageDraw.Draw(img)
empty.image(
img, caption=f"iter: {i}, loss: {loss:.2f}", width=target_resolution
)
# Update the handle points with point tracking
handle_points = point_tracking(
F_resized,
F0_resized,
handle_points,
handle_points_0,
r2,
device,
)
return torch.cat([W_layers_to_optimize, W[:, 6:]], dim=1).detach().cpu().numpy()
def motion_supervision(
F: torch.Tensor,
F0: torch.Tensor,
handle_points: torch.Tensor,
target_points: torch.Tensor,
r1: int = 3,
lambda_: float = 20.0,
device: torch.device = torch.device("cuda"),
multiplier: float = 1.0,
) -> Tuple[torch.Tensor, List[torch.Tensor]]:
"""
Computes the motion supervision loss and the shifted coordinates for each handle point.
Args:
F (torch.Tensor): The feature map tensor of shape [batch_size, num_channels, height, width].
F0 (torch.Tensor): The original feature map tensor of shape [batch_size, num_channels, height, width].
handle_points (torch.Tensor): The handle points tensor of shape [num_handle_points, 2].
target_points (torch.Tensor): The target points tensor of shape [num_handle_points, 2].
r1 (int): The radius of the circular mask around each handle point.
lambda_ (float): The weight of the reconstruction loss for the unmasked region.
device (torch.device): The device to use for the computation.
multiplier (float): The multiplier to use for the direction vector.
Returns:
A tuple containing the motion supervision loss tensor and a list of shifted coordinates
for each handle point, where each element in the list is a tensor of shape [num_points, 2].
"""
n = handle_points.shape[0] # Number of handle points
loss = 0.0
all_shifted_coordinates = [] # List of shifted patches
for i in range(n):
# Compute direction vector
target2handle = target_points[i] - handle_points[i]
d_i = target2handle / (torch.norm(target2handle) + 1e-7) * multiplier
if torch.norm(d_i) > torch.norm(target2handle):
d_i = target2handle
# Compute the mask for the pixels within radius r1 of the handle point
mask = utils.create_circular_mask(
F.shape[2], F.shape[3], center=handle_points[i].tolist(), radius=r1
).to(device)
# mask = utils.create_square_mask(F.shape[2], F.shape[3], center=handle_points[i].tolist(), radius=r1).to(device)
# Find indices where mask is True
coordinates = torch.nonzero(mask).float() # shape [num_points, 2]
# Shift the coordinates in the direction d_i
shifted_coordinates = coordinates + d_i[None]
all_shifted_coordinates.append(shifted_coordinates)
h, w = F.shape[2], F.shape[3]
# Extract features in the mask region and compute the loss
F_qi = F[:, :, mask] # shape: [C, H*W]
# Sample shifted patch from F
normalized_shifted_coordinates = shifted_coordinates.clone()
normalized_shifted_coordinates[:, 0] = (
2.0 * shifted_coordinates[:, 0] / (h - 1)
) - 1 # for height
normalized_shifted_coordinates[:, 1] = (
2.0 * shifted_coordinates[:, 1] / (w - 1)
) - 1 # for width
# Add extra dimensions for batch and channels (required by grid_sample)
normalized_shifted_coordinates = normalized_shifted_coordinates.unsqueeze(
0
).unsqueeze(
0
) # shape [1, 1, num_points, 2]
normalized_shifted_coordinates = normalized_shifted_coordinates.flip(
-1
) # grid_sample expects [x, y] instead of [y, x]
normalized_shifted_coordinates = normalized_shifted_coordinates.clamp(-1, 1)
# Use grid_sample to interpolate the feature map F at the shifted patch coordinates
F_qi_plus_di = torch.nn.functional.grid_sample(
F, normalized_shifted_coordinates, mode="bilinear", align_corners=True
)
# Output has shape [1, C, 1, num_points] so squeeze it
F_qi_plus_di = F_qi_plus_di.squeeze(2) # shape [1, C, num_points]
loss += torch.nn.functional.l1_loss(F_qi.detach(), F_qi_plus_di)
# TODO: add reconstruction loss for the unmasked region
# # Add reconstruction loss for the unmasked region
# loss += lambda_ * torch.norm((F - F0) * (1 - mask_total), p=1)
return loss, all_shifted_coordinates
def point_tracking(
F: torch.Tensor,
F0: torch.Tensor,
handle_points: torch.Tensor, # [N, y, x]
handle_points_0: torch.Tensor, # [N, y, x]
r2: int = 3,
device: torch.device = torch.device("cuda"),
) -> torch.Tensor:
"""
Tracks the movement of handle points in an image using feature matching.
Args:
F (torch.Tensor): The feature maps tensor of shape [batch_size, num_channels, height, width].
F0 (torch.Tensor): The feature maps tensor of shape [batch_size, num_channels, height, width] for the initial image.
handle_points (torch.Tensor): The handle points tensor of shape [N, y, x].
handle_points_0 (torch.Tensor): The handle points tensor of shape [N, y, x] for the initial image.
r2 (int): The radius of the patch around each handle point to use for feature matching.
device (torch.device): The device to use for the computation.
Returns:
The new handle points tensor of shape [N, y, x].
"""
n = handle_points.shape[0] # Number of handle points
new_handle_points = torch.zeros_like(handle_points)
for i in range(n):
# Compute the patch around the handle point
patch = utils.create_square_mask(
F.shape[2], F.shape[3], center=handle_points[i].tolist(), radius=r2
).to(device)
# Find indices where the patch is True
patch_coordinates = torch.nonzero(patch) # shape [num_points, 2]
# Extract features in the patch
F_qi = F[
:, :, patch_coordinates[:, 0], patch_coordinates[:, 1]
]
# Extract feature of the initial handle point
f_i = F0[
:, :, handle_points_0[i][0].long(), handle_points_0[i][1].long()
]
# Compute the L1 distance between the patch features and the initial handle point feature
distances = torch.norm(F_qi - f_i[:, :, None], p=1, dim=1)
# Find the new handle point as the one with minimum distance
min_index = torch.argmin(distances)
new_handle_points[i] = patch_coordinates[min_index]
return new_handle_points