Adversarial-Machine-Learnin.../Filter_Analysis/fgsm.py

142 lines
4.6 KiB
Python

import torch
import torch.nn as nn
import torch.nn.functional as F
import torch.optim as optim
from torchvision import datasets, transforms
import numpy as np
import matplotlib.pyplot as plt
import cv2
from mnist import Net
from pykuwahara import kuwahara
epsilons = np.arange(0.05,0.35,0.05)
pretrained_model = "data/lenet_mnist_model.pth"
use_cuda=False
torch.manual_seed(69)
test_loader = torch.utils.data.DataLoader(
datasets.MNIST('data/', train=False, download=True, transform=transforms.Compose([
transforms.ToTensor(),
transforms.Normalize((0.1307,), (0.3081,)),
])),
batch_size=1, shuffle=True)
print("CUDA Available: ", torch.cuda.is_available())
device = torch.device("cuda" if use_cuda and torch.cuda.is_available() else "cpu")
model = Net().to(device)
model.load_state_dict(torch.load(pretrained_model, map_location=device))
model.eval()
def fgsm_attack(image, epsilon, data_grad):
sign_data_grad = data_grad.sign()
perturbed_image = image + epsilon*sign_data_grad
perturbed_image = torch.clamp(perturbed_image, 0, 1)
return perturbed_image
def denorm(batch, mean=[0.1307], std=[0.3081]):
"""
Convert a batch of tensors to their original scale.
Args:
batch (torch.Tensor): Batch of normalized tensors.
mean (torch.Tensor or list): Man used for normalization.
std (torch.Tensor or list): Standard deviation used for normalization.
Returns:
torch.Tensor: batch of tensors without normalization applied to them.
"""
if isinstance(mean, list):
mean = torch.tensor(mean).to(device)
if isinstance(std, list):
std = torch.tensor(std).to(device)
return batch * std.view(1, -1, 1, 1) + mean.view(1, -1, 1, 1)
def test(model, device, test_loader, epsilon):
orig_correct = 0
attacked_correct = 0
filtered_correct = 0
adv_examples = []
incorrect=0
for data, target in test_loader:
data, target = data.to(device), target.to(device)
data.requires_grad = True
output_orig = model(data)
orig_pred = output_orig.max(1, keepdim=True)[1]
loss = F.nll_loss(output_orig, target)
model.zero_grad()
loss.backward()
data_grad = data.grad.data
data_denorm = denorm(data)
perturbed_data = fgsm_attack(data_denorm, epsilon, data_grad)
perturbed_data_normalized = transforms.Normalize((0.1307,), (0.3081,))(perturbed_data)
# convert the perturbed data tensor to a cv2 readable image
image = perturbed_data_normalized.detach().numpy().transpose(0,2,3,1)
# apply the Kuwahara filter
filtered_image = np.ndarray((1,28,28,1))
filtered_image[0] = kuwahara(image[0], method='gaussian', radius=3, image_2d=image[0])
# convert the cv2 image back to a torch tensor
filtered_image = filtered_image.transpose(0,3,1,2)
perturbed_data_filtered = torch.tensor(filtered_image).float()
# evaluate the model on the attacked and filtered images
output_attacked = model(perturbed_data_normalized)
output_filtered = model(perturbed_data_filtered)
attacked_pred = output_attacked.max(1, keepdim=True)[1]
filtered_pred = output_filtered.max(1, keepdim=True)[1]
if orig_pred.item() == target.item():
orig_correct += 1
else:
incorrect += 1
if attacked_pred.item() == target.item():
attacked_correct += 1
if epsilon == 0 and len(adv_examples) < 5:
adv_ex = perturbed_data.squeeze().detach().cpu().numpy()
adv_examples.append( (orig_pred.item(), attacked_pred.item(), adv_ex) )
if filtered_pred.item() == target.item():
filtered_correct += 1
if epsilon == 0 and len(adv_examples) < 5:
adv_ex = perturbed_data.squeeze().detach().cpu().numpy()
adv_examples.append( (orig_pred.item(), filtered_pred.item(), adv_ex) )
orig_acc = orig_correct/float(len(test_loader))
attacked_acc = attacked_correct/float(len(test_loader))
filtered_acc = filtered_correct/float(len(test_loader))
print(f"Epsilon: {epsilon}")
print(f"Original Accuracy = {orig_correct} / {len(test_loader)} = {orig_acc}")
print(f"Attacked Accuracy = {attacked_correct} / {len(test_loader)} = {attacked_acc}")
print(f"Filtered Accuracy = {filtered_correct} / {len(test_loader)} = {filtered_acc}")
return attacked_acc, adv_examples
accuracies = []
examples = []
for eps in epsilons:
acc, ex = test(model, device, test_loader, eps)
accuracies.append(acc)
examples.append(ex)