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train_MIAT.py
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train_MIAT.py
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import os
import argparse
import numpy as np
import torch.optim as optim
from torch.optim import lr_scheduler, Adam
from tqdm import tqdm
import torch
import torch.nn.functional as F
from torchvision import datasets, transforms
import torch.backends.cudnn as cudnn
from torch.autograd import Variable
from data import data_dataset
# from models.resnet_new import ResNet18
from models.wideresnet_new import WideResNet
from models.estimator import Estimator
from models.discriminators import MI1x1ConvNet, MIInternalConvNet, MIInternallastConvNet
from compute_MI import compute_loss
parser = argparse.ArgumentParser(description='PyTorch CIFAR MI AT')
parser.add_argument('--nat-img-train', type=str, help='natural training data', default='./data/train_images.npy')
parser.add_argument('--nat-label-train', type=str, help='natural training label', default='./data/train_labels.npy')
parser.add_argument('--nat-img-test', type=str, help='natural test data', default='./data/test_images.npy')
parser.add_argument('--nat-label-test', type=str, help='natural test label', default='./data/test_labels.npy')
parser.add_argument('--batch-size', type=int, default=256, metavar='N',
help='input batch size for training (default: 128)')
parser.add_argument('--epochs', type=int, default=100, metavar='N',
help='number of epochs to train')
# parser.add_argument('--lr-mi', type=float, default=1e-3, metavar='LR',
# help='learning rate')
parser.add_argument('--lr', type=float, default=1e-1, metavar='LR',
help='learning rate')
parser.add_argument('--weight-decay', '--wd', default=2e-4,
type=float, metavar='W')
parser.add_argument('--momentum', type=float, default=0.9, metavar='M',
help='SGD momentum')
parser.add_argument('--epsilon', default=8/255,
help='perturbation')
parser.add_argument('--num-steps', default=10,
help='perturb number of steps')
parser.add_argument('--step-size', default=0.007,
help='perturb step size')
parser.add_argument('--warm-up', type=bool, default=True,
help='warm up the MI estimator')
parser.add_argument('--warm-epochs', type=int, default=20, metavar='N',
help='number of epochs to train')
'''
parser.add_argument('--pretrain-model', default='./checkpoint/resnet_18/ori/best_model.pth',
help='directory of model for saving checkpoint')
'''
parser.add_argument('--pre-local-n', default='./checkpoint/resnet_18/MI_estimator/beta_final_l2/local_n_model.pth',
help='directory of model for saving checkpoint')
parser.add_argument('--pre-global-n', default='./checkpoint/resnet_18/MI_estimator/beta_final_l2/global_n_model.pth',
help='directory of model for saving checkpoint')
parser.add_argument('--pre-local-a', default='./checkpoint/resnet_18/MI_estimator/beta_final_l2/local_a_model.pth',
help='directory of model for saving checkpoint')
parser.add_argument('--pre-global-a', default='./checkpoint/resnet_18/MI_estimator/beta_final_l2/global_a_model.pth',
help='directory of model for saving checkpoint')
parser.add_argument('--va-mode', choices=['nce', 'fd', 'dv'], default='dv')
parser.add_argument('--va-fd-measure', default='JSD')
parser.add_argument('--va-hsize', type=int, default=2048)
parser.add_argument('--is_internal', type=bool, default=False)
parser.add_argument('--is_internal_last', type=bool, default=False)
parser.add_argument('--seed', type=int, default=1, metavar='S',
help='random seed (default: 1)')
parser.add_argument('--model-dir', default='./checkpoint/wideresnet/MIAT_standard',
help='directory of model for saving checkpoint')
parser.add_argument('--print_freq', type=int, default=50)
parser.add_argument('--save-freq', default=2, type=int, metavar='N', help='save frequency')
args = parser.parse_args()
class AverageMeter(object):
"""Computes and stores the average and current value"""
def __init__(self):
self.reset()
def reset(self):
self.val = 0
self.avg = 0
self.sum = 0
self.count = 0
def update(self, val, n=1):
self.val = val
self.sum += val * n
self.count += n
self.avg = self.sum / self.count
def setup_seed(seed):
torch.manual_seed(seed)
torch.cuda.manual_seed_all(seed)
np.random.seed(seed)
def make_optimizer_and_schedule(model, lr):
optimizer = Adam(model.parameters(), lr)
schedule = lr_scheduler.MultiStepLR(optimizer, milestones=[75, 90], gamma=0.1)
return optimizer, schedule
def adjust_learning_rate(optimizer, epoch):
"""decrease the learning rate"""
lr = args.lr
if epoch >= 90:
lr = args.lr * 0.01
elif epoch >= 75:
lr = args.lr * 0.1
for param_group in optimizer.param_groups:
param_group['lr'] = lr
def craft_adversarial_example_pgd(model, x_natural, y, step_size=0.007, epsilon=0.031, perturb_steps=20,
distance='l_inf'):
model.eval()
x_adv = x_natural.detach() + 0.001 * torch.randn(x_natural.shape).cuda().detach()
if distance == 'l_inf':
for _ in range(perturb_steps):
x_adv.requires_grad_()
with torch.enable_grad():
logits = model(x_adv)
loss_ce = F.cross_entropy(logits, y)
grad = torch.autograd.grad(loss_ce, [x_adv])[0]
x_adv = x_adv.detach() + step_size * torch.sign(grad.detach())
x_adv = torch.min(torch.max(x_adv, x_natural - epsilon), x_natural + epsilon)
x_adv = torch.clamp(x_adv, 0.0, 1.0)
elif distance == 'l_2':
batch_size = len(x_natural)
delta = 0.001 * torch.randn(x_natural.shape).cuda().detach()
delta = Variable(delta.data, requires_grad=True)
# Setup optimizers
optimizer_delta = optim.SGD([delta], lr=epsilon / perturb_steps * 2)
for _ in range(perturb_steps):
adv = x_natural + delta
# optimize
optimizer_delta.zero_grad()
with torch.enable_grad():
loss = (-1) * F.cross_entropy(model(adv), y)
loss.backward()
# renorming gradient
grad_norms = delta.grad.view(batch_size, -1).norm(p=2, dim=1)
delta.grad.div_(grad_norms.view(-1, 1, 1, 1))
# avoid nan or inf if gradient is 0
if (grad_norms == 0).any():
delta.grad[grad_norms == 0] = torch.randn_like(delta.grad[grad_norms == 0])
optimizer_delta.step()
# projection
delta.data.add_(x_natural)
delta.data.clamp_(0, 1).sub_(x_natural)
delta.data.renorm_(p=2, dim=0, maxnorm=epsilon)
x_adv = Variable(x_natural + delta, requires_grad=False)
else:
x_adv = torch.clamp(x_adv, 0.0, 1.0)
return x_adv
def MI_loss_nat(i, model, x_natural, y, x_adv, local_n, global_n, epoch):
model.train()
local_n.eval()
global_n.eval()
# logits_nat = model(x_natural)
logits_adv = model(x_adv)
loss_ce = F.cross_entropy(logits_adv, y)
# loss_ce = 0.2 * F.cross_entropy(logits_nat, y) + 0.8 * F.cross_entropy(logits_adv, y)
pesudo_label = F.softmax(model(x_natural), dim=0).max(1, keepdim=True)[1].squeeze()
index = (pesudo_label == y)
pesudo_label = F.softmax(model(x_adv), dim=0).max(1, keepdim=True)[1].squeeze()
index = index * (pesudo_label != y)
if torch.nonzero(index).size(0) != 0:
loss_n = compute_loss(args=args, former_input=x_natural, latter_input=x_natural, encoder=model,
dim_local=local_n, dim_global=global_n, v_out=True) * index
loss_a = compute_loss(args=args, former_input=x_natural, latter_input=x_adv, encoder=model,
dim_local=local_n, dim_global=global_n, v_out=True) * index
loss_mea = torch.abs(torch.tensor(1.0).cuda() - torch.cosine_similarity(loss_n, loss_a, dim=0))
loss_a = loss_a.sum()/torch.nonzero(index).size(0)
loss_mi = loss_mea + 0.1 * loss_a
else:
loss_mi = 0.0
loss_all = loss_ce + loss_mi
if (i + 1) % args.print_freq == 0:
print('select samples:' + str(torch.nonzero(index).size(0)))
print('Epoch [%d], Iter [%d/%d] Train target model. Natural MI: %.4f; Loss_ce: %.4f; Loss_all: %.4f'
% (epoch, i + 1, 50000 // args.batch_size, loss_mi.item(), loss_ce.item(), loss_all.item()))
return loss_all
def MI_loss(i, model, x_natural, y, x_adv, local_n, global_n, local_a, global_a, epoch):
model.train()
local_n.eval()
global_n.eval()
local_a.eval()
global_a.eval()
# logits_nat = model(x_natural)
logits_adv = model(x_adv)
loss_ce = F.cross_entropy(logits_adv, y)
# loss_ce = 0.2 * F.cross_entropy(logits_nat, y) + 0.8 * F.cross_entropy(logits_adv, y)
pesudo_label = F.softmax(model(x_natural), dim=0).max(1, keepdim=True)[1].squeeze()
index = (pesudo_label == y)
pesudo_label = F.softmax(model(x_adv), dim=0).max(1, keepdim=True)[1].squeeze()
index = index * (pesudo_label != y)
if torch.nonzero(index).size(0) != 0:
loss_n = compute_loss(args=args, former_input=x_natural, latter_input=x_natural, encoder=model,
dim_local=local_n, dim_global=global_n, v_out=True) * index
loss_a = compute_loss(args=args, former_input=x_natural, latter_input=x_adv, encoder=model,
dim_local=local_n, dim_global=global_n, v_out=True) * index
# loss_a_all = loss_a
loss_mea_n = torch.abs(torch.tensor(1.0).cuda() - torch.cosine_similarity(loss_n, loss_a, dim=0))
loss_a = compute_loss(args=args, former_input=x_adv - x_natural, latter_input=x_adv, encoder=model,
dim_local=local_a, dim_global=global_a, v_out=True) * index
loss_n = compute_loss(args=args, former_input=x_adv - x_natural, latter_input=x_natural, encoder=model,
dim_local=local_a, dim_global=global_a, v_out=True) * index
# loss_a_all = torch.tensor(0.1).cuda() * (loss_a_all - loss_a)
loss_mea_a = torch.abs(torch.tensor(1.0).cuda() - torch.cosine_similarity(loss_n, loss_a, dim=0))
loss_mi = loss_mea_n + loss_mea_a # + loss_a_all
else:
loss_mi = 0.0
loss_all = loss_ce + 5.0 * loss_mi
if (i + 1) % args.print_freq == 0:
print('select samples:' + str(torch.nonzero(index).size(0)))
print('Epoch [%d], Iter [%d/%d] Train target model. Natural MI: %.4f; Loss_ce: %.4f; Loss_all: %.4f'
% (epoch, i + 1, 50000 // args.batch_size, loss_mi.item(), loss_ce.item(), loss_all.item()))
return loss_all
def evaluate_mi_nat(encoder, x_natural, y, x_adv, local_n, global_n):
encoder.eval()
local_n.eval()
global_n.eval()
pesudo_label = F.softmax(encoder(x_natural), dim=0).max(1, keepdim=True)[1].squeeze()
index = (pesudo_label == y)
pesudo_label = F.softmax(encoder(x_adv), dim=0).max(1, keepdim=True)[1].squeeze()
index = index * (pesudo_label == y)
loss_r_n = (compute_loss(args=args, former_input=x_natural, latter_input=x_natural, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
loss_r_a = (compute_loss(args=args, former_input=x_natural, latter_input=x_adv, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
pesudo_label = F.softmax(encoder(x_natural), dim=0).max(1, keepdim=True)[1].squeeze()
index = (pesudo_label == y)
pesudo_label = F.softmax(encoder(x_adv), dim=0).max(1, keepdim=True)[1].squeeze()
index = index * (pesudo_label != y)
loss_w_n = (compute_loss(args=args, former_input=x_natural, latter_input=x_natural, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
loss_w_a = (compute_loss(args=args, former_input=x_natural, latter_input=x_adv, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
return loss_r_n, loss_r_a, loss_w_n, loss_w_a
def evaluate_mi_adv(encoder, x_natural, y, x_adv, local_n, global_n):
encoder.eval()
local_n.eval()
global_n.eval()
pesudo_label = F.softmax(encoder(x_natural), dim=0).max(1, keepdim=True)[1].squeeze()
index = (pesudo_label == y)
pesudo_label = F.softmax(encoder(x_adv), dim=0).max(1, keepdim=True)[1].squeeze()
index = index * (pesudo_label == y)
loss_r_n = (compute_loss(args=args, former_input=x_adv - x_natural, latter_input=x_natural, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
loss_r_a = (compute_loss(args=args, former_input=x_adv - x_natural, latter_input=x_adv, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
pesudo_label = F.softmax(encoder(x_natural), dim=0).max(1, keepdim=True)[1].squeeze()
index = (pesudo_label == y)
pesudo_label = F.softmax(encoder(x_adv), dim=0).max(1, keepdim=True)[1].squeeze()
index = index * (pesudo_label != y)
loss_w_n = (compute_loss(args=args, former_input=x_adv - x_natural, latter_input=x_natural, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
loss_w_a = (compute_loss(args=args, former_input=x_adv - x_natural, latter_input=x_adv, encoder=encoder,
dim_local=local_n, dim_global=global_n, v_out=True) * index).sum()/torch.nonzero(index).size(0)
return loss_r_n, loss_r_a, loss_w_n, loss_w_a
def eval_test(model, device, test_loader, local_n, global_n, local_a, global_a):
model.eval()
local_n.eval()
global_n.eval()
local_a.eval()
global_a.eval()
cnt = 0
correct = 0
correct_adv = 0
losses_r_n = 0
losses_r_a = 0
losses_w_n = 0
losses_w_a = 0
losses_r_n_1 = 0
losses_r_a_1 = 0
losses_w_n_1 = 0
losses_w_a_1 = 0
for data, target in test_loader:
cnt += 1
data, target = data.to(device), target.to(device)
data_adv = craft_adversarial_example_pgd(model=model, x_natural=data, y=target,
step_size=0.007, epsilon=8/255,
perturb_steps=40, distance='l_inf')
with torch.no_grad():
output = model(data)
output_adv = model(data_adv)
pred = output.max(1, keepdim=True)[1]
pred_adv = output_adv.max(1, keepdim=True)[1]
test_loss_r_n, test_loss_r_a, test_loss_w_n, test_loss_w_a = evaluate_mi_nat(encoder=model, x_natural=data,
y=target, x_adv=data_adv, local_n=local_n, global_n=global_n)
test_loss_r_n_1, test_loss_r_a_1, test_loss_w_n_1, test_loss_w_a_1 = evaluate_mi_nat(encoder=model, x_natural=data,
y=target, x_adv=data_adv,
local_n=local_a, global_n=global_a)
correct += pred.eq(target.view_as(pred)).sum().item()
correct_adv += pred_adv.eq(target.view_as(pred_adv)).sum().item()
losses_r_n += test_loss_r_n.item()
losses_r_a += test_loss_r_a.item()
losses_w_n += test_loss_w_n.item()
losses_w_a += test_loss_w_a.item()
losses_r_n_1 += test_loss_r_n_1.item()
losses_r_a_1 += test_loss_r_a_1.item()
losses_w_n_1 += test_loss_w_n_1.item()
losses_w_a_1 += test_loss_w_a_1.item()
test_accuracy = (correct_adv + correct) / (2.0 * len(test_loader.dataset))
print('Test: Accuracy: {}/{} ({:.2f}%), Robust Accuracy: {}/{} ({:.2f}%)'.format(correct, len(test_loader.dataset),
100. * correct / len(test_loader.dataset), correct_adv, len(test_loader.dataset),
100. * correct_adv / len(test_loader.dataset)))
print('Test: Natural MI Right: -n: {:.4f}, -a: {:.4f}'.format(
losses_r_n/cnt, losses_r_a/cnt))
print('Test: Natural MI Wrong: -n: {:.4f}, -a: {:.4f}'.format(
losses_w_n / cnt, losses_w_a / cnt))
print('Test: Adv MI Right: -n: {:.4f}, -a: {:.4f}'.format(
losses_r_n_1/cnt, losses_r_a_1/cnt))
print('Test: Adv MI Wrong: -n: {:.4f}, -a: {:.4f}'.format(
losses_w_n_1 / cnt, losses_w_a_1 / cnt))
return test_accuracy
def main():
# settings
setup_seed(args.seed)
os.environ["CUDA_VISIBLE_DEVICES"] = "0,1,2,3"
if not os.path.exists(args.model_dir):
os.makedirs(args.model_dir)
device = torch.device("cuda")
# setup data loader
trans_train = transforms.Compose([
transforms.RandomCrop(32, padding=4),
transforms.RandomHorizontalFlip(),
transforms.ToTensor()
])
trans_test = transforms.Compose([
transforms.ToTensor()
])
trainset = data_dataset(img_path=args.nat_img_train, clean_label_path=args.nat_label_train,
transform=trans_train)
train_loader = torch.utils.data.DataLoader(trainset, batch_size=args.batch_size, drop_last=False,
shuffle=True, num_workers=4, pin_memory=True)
testset = data_dataset(img_path=args.nat_img_test, clean_label_path=args.nat_label_test, transform=trans_test)
test_loader = torch.utils.data.DataLoader(testset, batch_size=args.batch_size, drop_last=False, shuffle=False,
num_workers=4, pin_memory=True)
# Estimator part 1: X or layer3 to H space
local_n = Estimator(args.va_hsize)
local_a = Estimator(args.va_hsize)
# estimator part 2: Z to H space
if args.is_internal == True:
if args.is_internal_last == True:
z_size = 512
global_n = MIInternallastConvNet(z_size, args.va_hsize)
global_a = MIInternallastConvNet(z_size, args.va_hsize)
else:
z_size = 256
global_n = MIInternalConvNet(z_size, args.va_hsize)
global_a = MIInternalConvNet(z_size, args.va_hsize)
else:
z_size = 10
global_n = MI1x1ConvNet(z_size, args.va_hsize)
global_a = MI1x1ConvNet(z_size, args.va_hsize)
# target_model = ResNet18(10)
target_model = WideResNet(34, 10, 10)
target_model = torch.nn.DataParallel(target_model).cuda()
local_n.load_state_dict(torch.load(args.pre_local_n))
global_n.load_state_dict(torch.load(args.pre_global_n))
local_a.load_state_dict(torch.load(args.pre_local_a))
global_a.load_state_dict(torch.load(args.pre_global_a))
local_n = torch.nn.DataParallel(local_n).cuda()
global_n = torch.nn.DataParallel(global_n).cuda()
local_a = torch.nn.DataParallel(local_a).cuda()
global_a = torch.nn.DataParallel(global_a).cuda()
cudnn.benchmark = True
optimizer = optim.SGD(target_model.parameters(), lr=args.lr, momentum=args.momentum, weight_decay=args.weight_decay)
# opt_local_n, schedule_local_n = make_optimizer_and_schedule(local_n, lr=args.lr_mi)
# opt_global_n, schedule_global_n = make_optimizer_and_schedule(global_n, lr=args.lr_mi)
# opt_local_a, schedule_local_a = make_optimizer_and_schedule(local_a, lr=args.lr_mi)
# opt_global_a, schedule_global_a = make_optimizer_and_schedule(global_a, lr=args.lr_mi)
# warm up
print('--------Warm up--------')
for epocah in range(0, 2):
for batch_idx, (data, target) in enumerate(train_loader):
target_model.train()
data, target = data.to(device), target.to(device)
logits_nat = target_model(data)
loss = F.cross_entropy(logits_nat, target)
optimizer.zero_grad()
loss.backward()
optimizer.step()
# Train
best_accuracy = 0
for epoch in range(1, args.epochs + 1):
adjust_learning_rate(optimizer, epoch)
print('--------Train the target model--------')
for batch_idx, (data, target) in enumerate(train_loader):
data, target = data.to(device), target.to(device)
# craft adversarial examples
adv = craft_adversarial_example_pgd(model=target_model, x_natural=data, y=target, step_size=0.007,
epsilon=8/255, perturb_steps=40, distance='l_inf')
# Train MI estimator
loss = MI_loss(i=batch_idx, model=target_model, x_natural=data, y=target, x_adv=adv, local_n=local_n,
global_n=global_n, local_a=local_a, global_a=global_a, epoch=epoch)
optimizer.zero_grad()
loss.backward()
optimizer.step()
# evaluation
print('--------Evaluate the target model--------')
test_accuracy = eval_test(model=target_model, device=device, test_loader=test_loader, local_n=local_n,
global_n=global_n, local_a=local_a, global_a=global_a)
# save checkpoint
if test_accuracy >= best_accuracy: # epoch % args.save_freq == 0:
best_accuracy = test_accuracy
'''
torch.save(model.module.state_dict(),
os.path.join(model_dir, 'model-epoch{}.pt'.format(epoch)))
'''
torch.save(target_model.module.state_dict(),
os.path.join(args.model_dir, 'target_model.pth'))
'''
torch.save(local_n.module.state_dict(),
os.path.join(args.model_dir, 'local_model.pth'))
torch.save(global_n.module.state_dict(),
os.path.join(args.model_dir, 'global_model.pth'))
'''
print('save the model')
print('================================================================')
if __name__ == '__main__':
main()