def batch(last, i, is_final, batch):
embeddings = last
# one image at a time
test_in = move_device(
test_trans(batch[0][0]).unsqueeze(0), P.cuda_device)
out = net(Variable(test_in, volatile=True)).data
embeddings[i] = out[0]
return embeddings
def create_batch(batch, n, epoch, similarities):
# one image at a time. batch is always of size 1
lab, (i1, i2), (im1, im2) = batch[0]
labels_in = tensor_t(torch.LongTensor, P.cuda_device, 1)
labels_in[0] = labels.index(lab)
# we get a positive couple. find negative for it
im3 = None
# choose a semi-hard negative. see FaceNet
# paper by Schroff et al for details.
# essentially, choose hardest negative that is still
# easier than the positive. this should avoid
# collapsing the model at beginning of training
ind_exl = lab_indicators[lab]
sim_pos = similarities[i1, i2]
if epoch < P.train_epoch_switch:
# exclude all positives as well as any that are
# more similar than sim_pos
ind_exl = ind_exl | similarities[i1].ge(sim_pos)
if ind_exl.sum() >= similarities.size(0):
p = 'cant find semi-hard neg for'
s = 'falling back to random neg'
n_pos = lab_indicators[lab].sum()
n_ge = similarities[i1].ge(sim_pos).sum()
n_tot = similarities.size(0)
print(
'{0} {1}-{2}-{3} (#pos:{4}, #ge:{5}, #total:{6}), {7}'.format(
p, i1, i2, lab, n_pos, n_ge, n_tot, s))
else:
# similarities must be in [-1, 1]
# set all similarities of excluded indexes to -2
# then take argmax (highest similarity not excluded)
sims = similarities[i1].clone()
sims[ind_exl] = -2
_, k = sims.max(0)
im3 = train_set[k[0]][0]
if im3 is None:
# default to random negative
im3 = choose_rand_neg(train_set, lab)
# one image at a time
train_in1 = move_device(train_trans(im1).unsqueeze(0), P.cuda_device)
train_in2 = move_device(train_trans(im2).unsqueeze(0), P.cuda_device)
train_in3 = move_device(train_trans(im3).unsqueeze(0), P.cuda_device)
# return input tensors and labels
return [train_in1, train_in2, train_in3], [labels_in]
def create_batch(batch, n):
# must proceed image by image (since different input sizes)
# each image/batch is composed of multiple scales
n_sc = len(batch[0][0])
train_in_scales = []
labels_in = tensor_t(torch.LongTensor, P.cuda_device, 1)
labels_in.fill_(labels.index(batch[0][1]))
for j in range(n_sc):
im = trans_scales[j](batch[0][0][j])
train_in = move_device(im.unsqueeze(0), P.cuda_device)
train_in_scales.append(train_in)
return train_in_scales, [labels_in]
def get_class_net():
model = models.alexnet
if P.cnn_model.lower() == 'resnet152':
model = models.resnet152
net = TuneClassif(model(pretrained=True),
len(labels),
untrained=P.untrained_blocks)
if P.preload_net:
net.load_state_dict(
torch.load(P.preload_net,
map_location=lambda storage, location: storage.cpu()))
net = move_device(net, P.cuda_device)
return net
def eval_batch_test(last, i, is_final, batch):
correct, total = last
im_trans = trans(batch[0][0])
test_in = move_device(im_trans.unsqueeze(0), P.cuda_device)
out = net(Variable(test_in, volatile=True))[0].data
# first get all maximal values for classification
# then, use the spatial region with the highest maximal value
# to make a prediction
max_pred, predicted = torch.max(out, 1)
_, max_subp = torch.max(max_pred.view(-1), 0)
predicted = predicted.view(-1)[max_subp[0]]
total += 1
correct += (labels.index(batch[0][1]) == predicted)
return correct, total
def batch(last, i, is_final, batch):
embeddings = last
im_trans = test_trans(batch[0][0])
test_in = move_device(im_trans.unsqueeze(0), P.cuda_device)
out = net(Variable(test_in, volatile=True))[0].data
# first, determine location of highest maximal activation
max_pred, _ = out.max(1)
max_pred1, max_i1 = max_pred.max(2)
_, max_i2 = max_pred1.max(3)
i2 = max_i2.view(-1)[0]
i1 = max_i1.view(-1)[i2]
# we have the indexes of the highest maximal activation,
# get the classification values at this point and normalize
out = out[:, :, i1, i2]
out = NormalizeL2Fun()(Variable(out, volatile=True))
out = out.data
embeddings[i] = out[0]
return embeddings
def get_siamese_net():
model = models.alexnet
if P.cnn_model.lower() == 'resnet152':
model = models.resnet152
class_net = TuneClassif(model(pretrained=True),
P.num_classes,
untrained=P.untrained_blocks)
if P.classif_model:
class_net.load_state_dict(
torch.load(P.classif_model,
map_location=lambda storage, location: storage.cpu()))
net = DescriptorNet(class_net,
P.feature_dim,
P.feature_size2d,
untrained=P.untrained_blocks)
if P.preload_net:
net.load_state_dict(
torch.load(P.preload_net,
map_location=lambda storage, location: storage.cpu()))
net = move_device(net, P.cuda_device)
return net
def get_class_net():
model = models.alexnet
if P.cnn_model.lower() == 'resnet152':
model = models.resnet152
if P.bn_model:
bn_model = TuneClassif(model(), len(labels))
bn_model.load_state_dict(
torch.load(P.bn_model,
map_location=lambda storage, location: storage.cpu()))
# copy_bn_all(net.features, bn_model.features)
else:
bn_model = model(pretrained=True)
net = TuneClassifSub(bn_model,
len(labels),
P.feature_size2d,
untrained=P.untrained_blocks)
if P.preload_net:
net.load_state_dict(
torch.load(P.preload_net,
map_location=lambda storage, location: storage.cpu()))
net = move_device(net, P.cuda_device)
return net
