def boundary_attack(model,
images,
labels,
targeted=False,
init=None,
max_iters=1000,
spherical_step=0.01,
source_step=0.01,
step_adaptation=1.5,
reset_step_every=50,
transformation=None,
dataset_name='imagenet',
blended_noise=False,
dct_mode='none',
dct_ratio=1.0,
repeat_images=1,
halve_every=250):
if transformation is None:
transformation = lambda x: x
images = images.cuda()
labels = labels.cuda()
batch_size = images.size(0)
base_preds, _ = utils.get_preds(model,
transformation(images.cuda()),
dataset_name,
batch_size=batch_size,
return_cpu=False)
images = images.repeat(repeat_images, 1, 1, 1)
labels = labels.repeat(repeat_images)
if repeat_images > 1:
multipliers = (torch.ones(repeat_images) * 2).pow(
torch.arange(0, repeat_images).float())
dct_ratio = torch.ones(batch_size) * dct_ratio
dct_ratio = (dct_ratio.unsqueeze(0).repeat(repeat_images, 1) *
multipliers.unsqueeze(1).repeat(1, batch_size)).view(
-1, 1).squeeze()
images_vec = images.view(batch_size, -1)
spherical_step_stats = torch.zeros(batch_size, max_iters)
source_step_stats = torch.zeros(batch_size, max_iters)
mse_stats = torch.zeros(batch_size, max_iters)
distance_stats = torch.zeros(batch_size, max_iters)
# sample random noise as initialization
init = torch.zeros(images.size()).cuda()
preds = labels.clone()
while preds.eq(labels).sum() > 0:
print("trying again")
idx = torch.arange(0, batch_size).long().cuda()[preds.eq(labels)]
noise = torch.rand(images[idx].size())
init[idx] = noise.cuda()
preds, _ = utils.get_preds(model,
transformation(init),
dataset_name,
batch_size=batch_size,
return_cpu=False)
if blended_noise:
min_alpha = torch.zeros(batch_size).cuda()
max_alpha = torch.ones(batch_size).cuda()
# binary search up to precision 2^(-10)
for _ in range(10):
alpha = (min_alpha + max_alpha) / 2
alpha_expanded = alpha.view(batch_size, 1, 1, 1).expand_as(init)
interp = alpha_expanded * init + (1 - alpha_expanded) * images
preds, _ = utils.get_preds(model,
transformation(interp),
dataset_name,
batch_size=batch_size,
return_cpu=False)
if targeted:
min_alpha[preds.ne(labels)] = alpha[preds.ne(labels)]
max_alpha[preds.eq(labels)] = alpha[preds.eq(labels)]
else:
min_alpha[preds.eq(labels)] = alpha[preds.eq(labels)]
max_alpha[preds.ne(labels)] = alpha[preds.ne(labels)]
alpha = max_alpha.view(batch_size, 1, 1, 1).expand_as(init)
perturbed = alpha * init + (1 - alpha) * images
else:
perturbed = init
# recording success rate of previous moves for adjusting step size
spherical_succ = torch.zeros(batch_size, reset_step_every).cuda()
source_succ = torch.zeros(batch_size, reset_step_every).cuda()
spherical_steps = (torch.ones(batch_size) * spherical_step).cuda()
source_steps = (torch.ones(batch_size) * source_step).cuda()
for i in range(max_iters):
candidates, spherical_candidates = generate_candidate(
images,
perturbed,
spherical_steps,
source_steps,
dct_mode=dct_mode,
dct_ratio=dct_ratio)
# additional query on spherical candidate for RGB-BA
if dct_mode:
spherical_preds = labels + 1
else:
spherical_preds, _ = utils.get_preds(
model,
transformation(spherical_candidates),
dataset_name,
batch_size=batch_size,
return_cpu=False)
source_preds, _ = utils.get_preds(model,
transformation(candidates),
dataset_name,
batch_size=batch_size,
return_cpu=False)
spherical_succ[:, i % reset_step_every][spherical_preds.ne(labels)] = 1
source_succ[:, i % reset_step_every][source_preds.ne(labels)] = 1
# reject moves if they result in correctly classified images
if source_preds.eq(labels).sum() > 0:
idx = torch.arange(
0, batch_size).long().cuda()[source_preds.eq(labels)]
candidates[idx] = perturbed[idx]
# reject moves if MSE is already low enough
if i > 0:
candidates[mse_prev.lt(1e-6)] = perturbed[mse_prev.lt(1e-6)]
# record some stats
perturbed_vec = perturbed.view(batch_size, -1)
candidates_vec = candidates.view(batch_size, -1)
mse_prev = (images_vec - perturbed_vec).pow(2).mean(1)
mse = (images_vec - candidates_vec).pow(2).mean(1)
reduction = 100 * (mse_prev.mean() - mse.mean()) / mse_prev.mean()
norms = (images_vec - candidates_vec).norm(2, 1)
print('Iteration %d: MSE = %.6f (reduced by %.4f%%), L2 norm = %.4f' %
(i + 1, mse.mean(), reduction, norms.mean()))
if (i + 1) % reset_step_every == 0:
# adjust step size
spherical_steps, source_steps, p_spherical, p_source = adjust_step(
spherical_succ,
source_succ,
spherical_steps,
source_steps,
step_adaptation,
dct_mode=dct_mode)
spherical_succ.fill_(0)
source_succ.fill_(0)
print('Spherical success rate = %.4f, new spherical step = %.4f' %
(p_spherical.mean(), spherical_steps.mean()))
print('Source success rate = %.4f, new source step = %.4f' %
(p_source.mean(), source_steps.mean()))
mse_stats[:, i] = mse
distance_stats[:, i] = norms
spherical_step_stats[:, i] = spherical_steps
source_step_stats[:, i] = source_steps
perturbed = candidates
if halve_every > 0 and perturbed.size(0) > batch_size and (
i + 1) % halve_every == 0:
# apply Hyperband to cut unsuccessful branches
num_repeats = int(batch_size / batch_size)
perturbed_vec = perturbed.view(batch_size, -1)
mse = (images_vec - perturbed_vec).pow(2).mean(1).view(
num_repeats, batch_size)
_, indices = mse.sort(0)
indices = indices[:int(num_repeats / 2)].cpu()
idx = torch.arange(0.0, float(batch_size)).unsqueeze(0).repeat(
int(num_repeats / 2), 1).long()
idx += indices * batch_size
idx = idx.view(-1, 1).squeeze()
batch_size = idx.size(0)
images = images[idx.cuda()]
labels = labels[idx.cuda()]
images_vec = images_vec[idx.cuda()]
perturbed = perturbed[idx.cuda()]
spherical_step_stats = spherical_step_stats[idx]
source_step_stats = source_step_stats[idx]
mse_stats = mse_stats[idx]
distance_stats = distance_stats[idx]
dct_ratio = dct_ratio[idx]
spherical_steps = spherical_steps[idx.cuda()]
source_steps = source_steps[idx.cuda()]
spherical_succ = spherical_succ[idx.cuda()]
source_succ = source_succ[idx.cuda()]
return perturbed.cpu(
), mse_stats, distance_stats, spherical_step_stats, source_step_stats
def inference_on_single_labelled_image_pca(
query_img_file,
labels_dir,
img_dir,
img_fts_dir,
weights_file,
top_k=1000,
plot=True,
):
"""
Function that returns the average precision for a given query image and also plots the top 20 results
Args:
query_img_file : path of query image file
labels_dir : Directory for ground truth labels
img_dir : Directory holding the images
img_fts_dir : Directory holding the pca reduced features generated through create_db.py script
weights_file: path of trained weights file
top_k : top_k values used to calculate the average precison
plot : if True, top 20 results are plotted
Returns:
Average precision for the query image file
"""
# Create cuda parameters
use_cuda = torch.cuda.is_available()
np.random.seed(2019)
torch.manual_seed(2019)
device = torch.device("cuda" if use_cuda else "cpu")
print("Available device = ", device)
# Create embedding network
resnet_model = create_embedding_net()
model = TripletNet(resnet_model)
model.load_state_dict(torch.load(weights_file))
model.to(device)
model.eval()
# Get query name
query_img_name = query_img_file.split("/")[-1]
query_img_path = os.path.join(img_dir, query_img_name)
# Create Query extractor object
QUERY_EXTRACTOR = QueryExtractor(labels_dir, img_dir, subset="inference")
# Create query ground truth dictionary
query_gt_dict = QUERY_EXTRACTOR.get_query_map()[query_img_name]
# Creat image database
QUERY_IMAGES_FTS = [
os.path.join(img_fts_dir, file)
for file in sorted(os.listdir(img_fts_dir))
]
QUERY_IMAGES = [
os.path.join(img_fts_dir, file) for file in sorted(os.listdir(img_dir))
]
# Query fts
query_fts = get_query_embedding(model, device,
query_img_file).detach().cpu().numpy()
query_fts = perform_pca_on_single_vector(query_fts)
# Create similarity list
similarity = []
for file in tqdm(QUERY_IMAGES_FTS):
file_fts = np.squeeze(np.load(file))
cos_sim = np.dot(query_fts, file_fts) / (np.linalg.norm(query_fts) *
np.linalg.norm(file_fts))
similarity.append(cos_sim)
# Get best matches using similarity
similarity = np.asarray(similarity)
indexes = (-similarity).argsort()[:top_k]
best_matches = [QUERY_IMAGES[index] for index in indexes]
# Get preds
if plot:
preds = get_preds_and_visualize(best_matches, query_gt_dict, img_dir,
20)
else:
preds = get_preds(best_matches, query_gt_dict)
# Get average precision
ap = ap_per_query(best_matches, query_gt_dict)
return ap
batchfile = '%s/images_%s_%d.pth' % (args.sampled_image_dir, args.model,
args.num_runs)
if os.path.isfile(batchfile):
checkpoint = torch.load(batchfile)
images = checkpoint['images']
labels = checkpoint['labels']
else:
images = torch.zeros(args.num_runs, 3, image_size, image_size)
labels = torch.zeros(args.num_runs).long()
preds = labels + 1
while preds.ne(labels).sum() > 0:
idx = torch.arange(0, images.size(0)).long()[preds.ne(labels)]
for i in list(idx):
images[i], labels[i] = testset[random.randint(0, len(testset) - 1)]
preds[idx], _ = utils.get_preds(model,
images[idx],
'imagenet',
batch_size=args.batch_size)
torch.save({'images': images, 'labels': labels}, batchfile)
if args.order == 'rand':
n_dims = 3 * args.freq_dims * args.freq_dims
else:
n_dims = 3 * image_size * image_size
if args.num_iters > 0:
max_iters = int(min(n_dims, args.num_iters))
else:
max_iters = int(n_dims)
N = int(math.floor(float(args.num_runs) / float(args.batch_size)))
for i in range(N):
upper = min((i + 1) * args.batch_size, args.num_runs)
images_batch = images[(i * args.batch_size):upper]
