def test_binary_jaccard_loss():
eps = 1e-5
criterion = JaccardLoss(mode=smp.losses.BINARY_MODE, from_logits=False)
# Ideal case
y_pred = torch.tensor([1.0]).view(1, 1, 1, 1)
y_true = torch.tensor(([1])).view(1, 1, 1, 1)
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(0.0, abs=eps)
y_pred = torch.tensor([1.0, 0.0, 1.0]).view(1, 1, 1, -1)
y_true = torch.tensor(([1, 0, 1])).view(1, 1, 1, -1)
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(0.0, abs=eps)
y_pred = torch.tensor([0.0, 0.0, 0.0]).view(1, 1, 1, -1)
y_true = torch.tensor(([0, 0, 0])).view(1, 1, 1, -1)
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(0.0, abs=eps)
# Worst case
y_pred = torch.tensor([1.0, 1.0, 1.0]).view(1, 1, -1)
y_true = torch.tensor([0, 0, 0]).view(1, 1, 1, -1)
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(0.0, abs=eps)
y_pred = torch.tensor([1.0, 0.0, 1.0]).view(1, 1, -1)
y_true = torch.tensor([0, 1, 0]).view(1, 1, 1, -1)
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(1.0, eps)
y_pred = torch.tensor([0.0, 0.0, 0.0]).view(1, 1, -1)
y_true = torch.tensor([1, 1, 1]).view(1, 1, 1, -1)
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(1.0, eps)
def train(num_epochs, model, data_loader, val_loader, val_every, device, file_name):
learning_rate = 0.0001
from torch.optim.swa_utils import AveragedModel, SWALR
from torch.optim.lr_scheduler import CosineAnnealingLR
from segmentation_models_pytorch.losses import SoftCrossEntropyLoss, JaccardLoss
from adamp import AdamP
criterion = [SoftCrossEntropyLoss(smooth_factor=0.1), JaccardLoss('multiclass', classes=12)]
optimizer = AdamP(params=model.parameters(), lr=learning_rate, weight_decay=1e-6)
swa_scheduler = SWALR(optimizer, swa_lr=learning_rate)
swa_model = AveragedModel(model)
look = Lookahead(optimizer, la_alpha=0.5)
print('Start training..')
best_miou = 0
for epoch in range(num_epochs):
hist = np.zeros((12, 12))
model.train()
for step, (images, masks, _) in enumerate(data_loader):
loss = 0
images = torch.stack(images) # (batch, channel, height, width)
masks = torch.stack(masks).long() # (batch, channel, height, width)
# gpu 연산을 위해 device 할당
images, masks = images.to(device), masks.to(device)
# inference
outputs = model(images)
for i in criterion:
loss += i(outputs, masks)
# loss 계산 (cross entropy loss)
look.zero_grad()
loss.backward()
look.step()
outputs = torch.argmax(outputs.squeeze(), dim=1).detach().cpu().numpy()
hist = add_hist(hist, masks.detach().cpu().numpy(), outputs, n_class=12)
acc, acc_cls, mIoU, fwavacc = label_accuracy_score(hist)
# step 주기에 따른 loss, mIoU 출력
if (step + 1) % 25 == 0:
print('Epoch [{}/{}], Step [{}/{}], Loss: {:.4f}, mIoU: {:.4f}'.format(
epoch + 1, num_epochs, step + 1, len(data_loader), loss.item(), mIoU))
# validation 주기에 따른 loss 출력 및 best model 저장
if (epoch + 1) % val_every == 0:
avrg_loss, val_miou = validation(epoch + 1, model, val_loader, criterion, device)
if val_miou > best_miou:
print('Best performance at epoch: {}'.format(epoch + 1))
print('Save model in', saved_dir)
best_miou = val_miou
save_model(model, file_name = file_name)
if epoch > 3:
swa_model.update_parameters(model)
swa_scheduler.step()
def test_multilabel_jaccard_loss():
eps = 1e-5
criterion = JaccardLoss(mode=smp.losses.MULTILABEL_MODE, from_logits=False)
# Ideal case
y_pred = torch.tensor([[[1.0, 1.0, 0.0, 0.0], [0.0, 0.0, 1.0, 1.0]]])
y_true = torch.tensor([[[1.0, 1.0, 0.0, 0.0], [0.0, 0.0, 1.0, 1.0]]])
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(0.0, abs=eps)
# Worst case
y_pred = torch.tensor([[[1.0, 1.0, 0.0, 0.0], [0.0, 0.0, 1.0, 1.0]]])
y_true = 1 - y_pred
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(1.0, abs=eps)
# 1 - 1/3 case
y_pred = torch.tensor([[[0.0, 1.0, 1.0, 0.0], [0.0, 1.0, 1.0, 0.0]]])
y_true = torch.tensor([[[1.0, 1.0, 0.0, 0.0], [1.0, 1.0, 0.0, 0.0]]])
loss = criterion(y_pred, y_true)
assert float(loss) == pytest.approx(1.0 - 1.0 / 3.0, abs=eps)
def pseudo_labeling(num_epochs, model, data_loader, val_loader,
unlabeled_loader, device, val_every, file_name):
# Instead of using current epoch we use a "step" variable to calculate alpha_weight
# This helps the model converge faster
from torch.optim.swa_utils import AveragedModel, SWALR
from segmentation_models_pytorch.losses import SoftCrossEntropyLoss, JaccardLoss
from adamp import AdamP
criterion = [
SoftCrossEntropyLoss(smooth_factor=0.1),
JaccardLoss('multiclass', classes=12)
]
optimizer = AdamP(params=model.parameters(), lr=0.0001, weight_decay=1e-6)
swa_scheduler = SWALR(optimizer, swa_lr=0.0001)
swa_model = AveragedModel(model)
optimizer = Lookahead(optimizer, la_alpha=0.5)
step = 100
size = 256
best_mIoU = 0
model.train()
print('Start Pseudo-Labeling..')
for epoch in range(num_epochs):
hist = np.zeros((12, 12))
for batch_idx, (imgs, image_infos) in enumerate(unlabeled_loader):
# Forward Pass to get the pseudo labels
# --------------------------------------------- test(unlabelse)를 모델에 통과
model.eval()
outs = model(torch.stack(imgs).to(device))
oms = torch.argmax(outs.squeeze(), dim=1).detach().cpu().numpy()
oms = torch.Tensor(oms)
oms = oms.long()
oms = oms.to(device)
# --------------------------------------------- 학습
model.train()
# Now calculate the unlabeled loss using the pseudo label
imgs = torch.stack(imgs)
imgs = imgs.to(device)
# preds_array = preds_array.to(device)
output = model(imgs)
loss = 0
for each in criterion:
loss += each(output, oms)
unlabeled_loss = alpha_weight(step) * loss
# Backpropogate
optimizer.zero_grad()
unlabeled_loss.backward()
optimizer.step()
output = torch.argmax(output.squeeze(),
dim=1).detach().cpu().numpy()
hist = add_hist(hist,
oms.detach().cpu().numpy(),
output,
n_class=12)
if (batch_idx + 1) % 25 == 0:
acc, acc_cls, mIoU, fwavacc = label_accuracy_score(hist)
print('Epoch [{}/{}], Step [{}/{}], Loss: {:.4f}, mIoU:{:.4f}'.
format(epoch + 1, num_epochs, batch_idx + 1,
len(unlabeled_loader), unlabeled_loss.item(),
mIoU))
# For every 50 batches train one epoch on labeled data
# 50배치마다 라벨데이터를 1 epoch학습
if batch_idx % 50 == 0:
# Normal training procedure
for batch_idx, (images, masks, _) in enumerate(data_loader):
labeled_loss = 0
images = torch.stack(images)
# (batch, channel, height, width)
masks = torch.stack(masks).long()
# gpu 연산을 위해 device 할당
images, masks = images.to(device), masks.to(device)
output = model(images)
for each in criterion:
labeled_loss += each(output, masks)
optimizer.zero_grad()
labeled_loss.backward()
optimizer.step()
# Now we increment step by 1
step += 1
if (epoch + 1) % val_every == 0:
avrg_loss, val_mIoU = validation(epoch + 1, model, val_loader,
criterion, device)
if val_mIoU > best_mIoU:
print('Best performance at epoch: {}'.format(epoch + 1))
print('Save model in', saved_dir)
best_mIoU = val_mIoU
save_model(model, file_name=file_name)
model.train()
if epoch > 3:
swa_model.update_parameters(model)
swa_scheduler.step()
