def train_one_epoch(model,
optimizer,
data_loader,
device,
epoch,
print_freq=1000):
"""
Train model (JointDetector) for 1 epoch from data in data_loader (images, obj_targets, part_targets)
"""
model.train()
metric_logger = MetricLogger(delimiter=" ")
metric_logger.add_meter('lr',
SmoothedValue(window_size=1, fmt='{value:.6f}'))
header = 'Epoch: [{}]'.format(epoch)
lr_scheduler = None
if epoch == 0:
warmup_factor = 1. / 1000
warmup_iters = min(1000, len(data_loader) - 1)
lr_scheduler = warmup_lr_scheduler(optimizer, warmup_iters,
warmup_factor)
for images, obj_targets, part_targets in metric_logger.log_every(
data_loader, print_freq, header, device):
images = list(image.to(device) for image in images)
obj_targets = [{k: v.to(device)
for k, v in t.items()} for t in obj_targets]
part_targets = [{k: v.to(device)
for k, v in t.items()} for t in part_targets]
loss_dict = model(images, obj_targets, part_targets)
losses = sum(loss for loss in loss_dict.values())
# reduce losses over all GPUs for logging purposes
loss_dict_reduced = reduce_dict(loss_dict)
losses_reduced = sum(loss for loss in loss_dict_reduced.values())
loss_value = losses_reduced.item()
if not math.isfinite(loss_value):
print('Loss is {}, stopping training'.format(loss_value))
print(loss_dict_reduced)
sys.exit(1)
optimizer.zero_grad()
losses.backward()
optimizer.step()
if lr_scheduler is not None:
lr_scheduler.step()
metric_logger.update(loss=losses_reduced, **loss_dict_reduced)
metric_logger.update(lr=optimizer.param_groups[0]["lr"])
return metric_logger
def train_one_epoch_SSD(model, loss_func, optimizer, data_loader, encoder,
epoch, print_freq, mean, std, device):
model.train()
metric_logger = utils.MetricLogger(delimiter=" ")
metric_logger.add_meter(
'lr', utils.SmoothedValue(window_size=1, fmt='{value:.6f}'))
header = 'Epoch: [{}]'.format(epoch)
lr_scheduler = None
losses = AverageMeter()
if epoch == 0:
warmup_factor = 1. / 1000
warmup_iters = min(1000, len(data_loader) - 1)
lr_scheduler = utils.warmup_lr_scheduler(optimizer, warmup_iters,
warmup_factor)
criterion = MultiBoxLoss(priors_cxcy=model.priors_cxcy).to(device)
dboxes = dboxes300_coco()
loss_func = Loss(dboxes)
for images, targets in metric_logger.log_every(data_loader, print_freq,
header):
images = torch.stack(images).to(device)
bboxes = [t["boxes"].to(device) for t in targets]
labels = [t["labels"].to(device) for t in targets]
ploc, pscores = model(images)
ploc, pscores = ploc.float(), pscores.float()
# loss
loss = criterion(ploc, pscores, bboxes, labels)
# Backward prop.
optimizer.zero_grad()
loss.backward()
# Update model
optimizer.step()
losses.update(loss.item(), images.size(0))
metric_logger.update(loss=losses.val, **{})
metric_logger.update(lr=optimizer.param_groups[0]["lr"])
def main(args):
utils.init_distributed_mode(args)
print(args)
device = torch.device(args.device)
# Creating tensorboard writer
if not args.resume:
writer = SummaryWriter(comment=TENSORBOARD_RESULT_FILE_NAME)
else:
writer = SummaryWriter("")
######################
# Creating test data #
######################
print("Loading test data")
viped_dataset_test = get_dataset("viped",
get_transform(train=False, aug=args.aug),
percentage=5,
val=True)
mot19_dataset_test = get_dataset("mot19",
get_transform(train=False),
val=True)
mot17_dataset_test = get_dataset("mot17",
get_transform(train=False),
val=True)
crowd_human_dataset_test = get_dataset("crowd_human",
get_transform(train=False),
val=True)
city_persons_dataset_test = get_dataset("city_persons",
get_transform(train=False),
val=True)
coco_persons_dataset_test = get_dataset("COCO_persons",
get_transform(train=False),
val=True)
##########################
# Creating training data #
##########################
print("Loading training data")
train_datasets_dict = {
'viped':
lambda: get_dataset("viped", get_transform(train=True, aug=args.aug)),
'mot19':
lambda: get_dataset("mot19", get_transform(train=True)),
'mot17':
lambda: get_dataset("mot17", get_transform(train=True)),
'crowd_human':
lambda: get_dataset("crowd_human", get_transform(train=True)),
'city_persons':
lambda: get_dataset("city_persons", get_transform(train=True)),
'COCO_persons:':
lambda: get_dataset("COCO_persons", get_transform(train=True)),
}
#################################
# Preparing training dataloader #
#################################
if args.train_on in train_datasets_dict:
# the train dataset is a normal single dataset
train_dataset = train_datasets_dict[args.train_on]()
train_dataloader = DataLoader(
train_dataset,
batch_size=args.batch_size,
shuffle=True,
num_workers=args.workers,
collate_fn=train_dataset.standard_collate_fn)
print('Using training dataset: {}'.format(args.train_on))
elif ',' in args.train_on:
assert args.tgt_images_in_batch > 0, "Using mixed training. " \
"You need to specify the args.tgt_images_in_batch parameter!"
# the train dataset is an ensamble of datasets
source_dataset_name, target_dataset_name = args.train_on.split(',')
train_dataset = DatasetsEnsemble(
train_datasets_dict[source_dataset_name](),
train_datasets_dict[target_dataset_name]())
train_dataloader = DataLoader(
train_dataset,
collate_fn=train_dataset.source_dataset.standard_collate_fn,
num_workers=args.workers,
batch_sampler=EnsembleBatchSampler(
train_dataset,
batch_size=args.batch_size,
shuffle=True,
tgt_imgs_in_batch=args.tgt_images_in_batch))
print(
'Using mixed training datasets. Source: {}, Target: {}. In every batch, {}/{} are from {}'
.format(source_dataset_name, target_dataset_name,
args.tgt_images_in_batch, args.batch_size,
target_dataset_name))
else:
raise ValueError('Dataset not known!')
##############################
# Preparing test dataloaders #
##############################
data_loader_viped_test = DataLoader(
viped_dataset_test,
batch_size=args.batch_size,
shuffle=False,
num_workers=args.workers,
collate_fn=viped_dataset_test.standard_collate_fn)
data_loader_mot19_test = DataLoader(
mot19_dataset_test,
batch_size=args.batch_size,
shuffle=False,
num_workers=args.workers,
collate_fn=mot19_dataset_test.standard_collate_fn)
data_loader_mot17_test = DataLoader(
mot17_dataset_test,
batch_size=args.batch_size,
shuffle=False,
num_workers=args.workers,
collate_fn=mot17_dataset_test.standard_collate_fn)
data_loader_crowd_human_test = DataLoader(
crowd_human_dataset_test,
batch_size=args.batch_size,
shuffle=False,
num_workers=args.workers,
collate_fn=crowd_human_dataset_test.standard_collate_fn)
data_loader_city_persons_test = DataLoader(
city_persons_dataset_test,
batch_size=args.batch_size,
shuffle=False,
num_workers=args.workers,
collate_fn=city_persons_dataset_test.standard_collate_fn)
data_loader_coco_persons_test = DataLoader(
coco_persons_dataset_test,
shuffle=False,
num_workers=args.workers,
collate_fn=coco_persons_dataset_test.standard_collate_fn)
# Creating model
print("Creating model")
model, backbone = get_model_detection(num_classes=1,
model=args.model,
pretrained=args.pretrained)
# Putting model to device and setting eval mode
model.to(device)
model.train()
# freeze the backbone parameters, if needed
if backbone is not None and args.freeze_backbone:
for param in backbone.parameters():
param.requires_grad = False
print('Backbone is freezed!')
# construct an optimizer
params = [p for p in model.parameters() if p.requires_grad]
if args.optimizer == "sgd":
optimizer = torch.optim.SGD(params,
lr=args.lr,
momentum=args.momentum,
weight_decay=args.weight_decay)
elif args.optimizer == "adam":
optimizer = torch.optim.Adam(
params=params,
lr=args.lr,
)
else:
print("Optimizer not available")
exit(1)
# and a learning rate scheduler
if args.lr_scheduler == "step_lr":
lr_scheduler = torch.optim.lr_scheduler.StepLR(
optimizer, step_size=args.lr_step_size, gamma=args.lr_gamma)
elif args.lr_scheduler == "plateau":
lr_scheduler = torch.optim.lr_scheduler.ReduceLROnPlateau(
optimizer, mode='max', patience=args.lr_patience, verbose=True)
else:
print("L-Scheduler not available")
exit(1)
# Defining a warm-uo lr scheduler
warmup_iters = min(1000, len(train_dataloader) - 1)
warmup_factor = 1. / 1000
warmup_lr_scheduler = utils.warmup_lr_scheduler(optimizer, warmup_iters,
warmup_factor)
# Loading checkpoint
start_epoch = 0
train_step = -1
best_viped_ap, best_mot19_ap, best_mot17_ap, best_crowdhuman_ap, best_citypersons_ap, best_cocopersons_ap \
= 0, 0, 0, 0, 0, 0
if args.resume:
print("Resuming from checkpoint")
checkpoint = torch.load(args.resume)
model.load_state_dict(checkpoint['model'])
optimizer.load_state_dict(checkpoint['optimizer'])
lr_scheduler.load_state_dict(checkpoint['lr_scheduler'])
warmup_lr_scheduler.load_state_dict(checkpoint['warmup_lr_scheduler'])
start_epoch = checkpoint['epoch']
train_step = checkpoint['iteration']
best_viped_ap = checkpoint['best_viped_ap']
best_mot19_ap = checkpoint['best_mot19_ap']
best_mot17_ap = checkpoint['best_mot17_ap']
best_crowdhuman_ap = checkpoint['best_crowdhuman_ap']
best_citypersons_ap = checkpoint['best_citypersons_ap']
best_cocopersons_ap = checkpoint['best_cocopersons_ap']
# Cross-check if the backbone has been really freezed
if backbone is not None and args.freeze_backbone:
for param in backbone.parameters():
assert not param.requires_grad, "Backbone seems to be not freezed correctly!"
# Train
print("Start training")
for epoch in range(start_epoch, args.epochs):
model.train()
metric_logger = utils.MetricLogger(delimiter=" ")
metric_logger.add_meter(
'lr', utils.SmoothedValue(window_size=1, fmt='{value:.6f}'))
header = 'Epoch: [{}]'.format(epoch)
for images, targets in metric_logger.log_every(
train_dataloader, print_freq=args.print_freq, header=header):
train_step += 1
images = list(image.to(device) for image in images)
targets = [{k: v.to(device)
for k, v in t.items()} for t in targets]
loss_dict = model(images, targets)
losses = sum(loss for loss in loss_dict.values())
# reduce losses over all GPUs for logging purposes
loss_dict_reduced = utils.reduce_dict(loss_dict)
losses_reduced = sum(loss for loss in loss_dict_reduced.values())
loss_value = losses_reduced.item()
if not math.isfinite(loss_value):
print("Loss is {}, stopping training".format(loss_value))
print(loss_dict_reduced)
sys.exit(1)
optimizer.zero_grad()
losses.backward()
# clip norm
torch.nn.utils.clip_grad_norm(model.parameters(), 50)
optimizer.step()
if epoch == 0 and train_step < warmup_iters:
warmup_lr_scheduler.step()
metric_logger.update(loss=losses_reduced, **loss_dict_reduced)
metric_logger.update(lr=optimizer.param_groups[0]["lr"])
if train_step % args.log_loss == 0:
writer.add_scalar('Training/Learning Rate',
optimizer.param_groups[0]["lr"], train_step)
writer.add_scalar('Training/Reduced Sum Losses',
losses_reduced, train_step)
writer.add_scalars('Training/All Losses', loss_dict,
train_step)
if (train_step % args.save_freq == 0 and train_step != 0) or \
(args.pretrained and train_step < 5*args.save_freq and train_step % 200 == 0 and train_step != 0) \
or train_step == 100:
# evaluate on the test datasets
print("Validation viped Dataset")
viped_coco_evaluator = evaluate(model,
data_loader_viped_test,
device=device,
max_dets=args.max_dets)
print("Validation mot19 Dataset")
mot19_coco_evaluator = evaluate(model,
data_loader_mot19_test,
device=device,
max_dets=args.max_dets)
print("Validation mot17 Dataset")
mot17_coco_evaluator = evaluate(model,
data_loader_mot17_test,
device=device,
max_dets=args.max_dets)
print("Validation crowdhuman Dataset")
crowdhuman_coco_evaluator = evaluate(
model,
data_loader_crowd_human_test,
device=device,
max_dets=args.max_dets)
print("Validation citypersons Dataset")
citypersons_coco_evaluator = evaluate(
model,
data_loader_city_persons_test,
device=device,
max_dets=args.max_dets)
print("Validation COCO Persons Dataset")
cocopersons_coco_evaluator = evaluate(
model,
data_loader_coco_persons_test,
device=device,
max_dets=args.max_dets)
# save using tensorboard
viped_ap, mot19_ap, mot17_ap, crowdhuman_ap, citypersons_ap, cocopersons_ap = \
None, None, None, None, None, None
for iou_type, coco_eval in viped_coco_evaluator.coco_eval.items(
):
viped_ap = coco_eval.stats[1]
for iou_type, coco_eval in mot19_coco_evaluator.coco_eval.items(
):
mot19_ap = coco_eval.stats[1]
for iou_type, coco_eval in mot17_coco_evaluator.coco_eval.items(
):
mot17_ap = coco_eval.stats[1]
for iou_type, coco_eval in crowdhuman_coco_evaluator.coco_eval.items(
):
crowdhuman_ap = coco_eval.stats[1]
for iou_type, coco_eval in citypersons_coco_evaluator.coco_eval.items(
):
citypersons_ap = coco_eval.stats[1]
for iou_type, coco_eval in cocopersons_coco_evaluator.coco_eval.items(
):
cocopersons_ap = coco_eval.stats[1]
writer.add_scalar('COCO mAP Validation/ViPeD', viped_ap,
train_step)
writer.add_scalar('COCO mAP Validation/MOT19', mot19_ap,
train_step)
writer.add_scalar('COCO mAP Validation/MOT17', mot17_ap,
train_step)
writer.add_scalar('COCO mAP Validation/CrowdHuman',
crowdhuman_ap, train_step)
writer.add_scalar('COCO mAP Validation/CityPersons',
citypersons_ap, train_step)
writer.add_scalar('COCO mAP Validation/COCOPersons',
cocopersons_ap, train_step)
# Eventually saving best models
if viped_ap > best_viped_ap:
best_viped_ap = viped_ap
save_checkpoint(
{
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'best_viped_ap':
best_viped_ap,
'best_mot19_ap':
best_mot19_ap,
'best_mot17_ap':
best_mot17_ap,
'best_crowdhuman_ap':
best_crowdhuman_ap,
'best_citypersons_ap':
best_citypersons_ap,
'best_cocopersons_ap':
best_cocopersons_ap,
},
writer.get_logdir(),
best_model="viped")
if mot19_ap > best_mot19_ap:
best_mot19_ap = mot19_ap
save_checkpoint(
{
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'best_viped_ap':
best_viped_ap,
'best_mot19_ap':
best_mot19_ap,
'best_mot17_ap':
best_mot17_ap,
'best_crowdhuman_ap':
best_crowdhuman_ap,
'best_citypersons_ap':
best_citypersons_ap,
'best_cocopersons_ap':
best_cocopersons_ap,
},
writer.get_logdir(),
best_model="mot19")
if mot17_ap > best_mot17_ap:
best_mot17_ap = mot17_ap
save_checkpoint(
{
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'best_viped_ap':
best_viped_ap,
'best_mot19_ap':
best_mot19_ap,
'best_mot17_ap':
best_mot17_ap,
'best_crowdhuman_ap':
best_crowdhuman_ap,
'best_citypersons_ap':
best_citypersons_ap,
'best_cocopersons_ap':
best_cocopersons_ap,
},
writer.get_logdir(),
best_model="mot17")
if crowdhuman_ap > best_crowdhuman_ap:
best_crowdhuman_ap = crowdhuman_ap
save_checkpoint(
{
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'best_viped_ap':
best_viped_ap,
'best_mot19_ap':
best_mot19_ap,
'best_mot17_ap':
best_mot17_ap,
'best_crowdhuman_ap':
best_crowdhuman_ap,
'best_citypersons_ap':
best_citypersons_ap,
'best_cocopersons_ap':
best_cocopersons_ap,
},
writer.get_logdir(),
best_model="crowdhuman")
if citypersons_ap > best_citypersons_ap:
best_citypersons_ap = citypersons_ap
save_checkpoint(
{
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'best_viped_ap':
best_viped_ap,
'best_mot19_ap':
best_mot19_ap,
'best_mot17_ap':
best_mot17_ap,
'best_crowdhuman_ap':
best_crowdhuman_ap,
'best_citypersons_ap':
best_citypersons_ap,
'best_cocopersons_ap':
best_cocopersons_ap,
},
writer.get_logdir(),
best_model="citypersons")
# Saving model
save_checkpoint(
{
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'best_viped_ap':
best_viped_ap,
'best_mot19_ap':
best_mot19_ap,
'best_mot17_ap':
best_mot17_ap,
'best_crowdhuman_ap':
best_crowdhuman_ap,
'best_citypersons_ap':
best_citypersons_ap,
'best_cocopersons_ap':
best_cocopersons_ap,
}, writer.get_logdir())
# Setting again to train mode
model.train()
lr_scheduler.step()
def main(args):
utils.init_distributed_mode(args)
print(args)
# Opening YAML cfg config file
with open(args.cfg_file, 'r') as stream:
try:
cfg_file = yaml.safe_load(stream)
except yaml.YAMLError as exc:
print(exc)
# Retrieving cfg
train_cfg = cfg_file['training']
model_cfg = cfg_file['model']
data_cfg = cfg_file['dataset']
# Setting device
device = torch.device(model_cfg['device'])
# No possible to set checkpoint and pre-trained model at the same time
if train_cfg['checkpoint'] and train_cfg['pretrained_model']:
print("You can't set checkpoint and pretrained-model at the same time")
exit(1)
# Creating tensorboard writer
if train_cfg['checkpoint']:
checkpoint = torch.load(train_cfg['checkpoint'])
writer = SummaryWriter(log_dir=checkpoint['tensorboard_working_dir'])
else:
writer = SummaryWriter(comment="_" + train_cfg['tensorboard_filename'])
# Saving cfg file in the same folder
copyfile(
args.cfg_file,
os.path.join(writer.get_logdir(), os.path.basename(args.cfg_file)))
#######################
# Creating model
#######################
print("Creating model")
load_custom_model = False
if train_cfg['checkpoint'] or train_cfg['pretrained_model']:
load_custom_model = True
model, backbone = get_model_detection(num_classes=1,
cfg=model_cfg,
load_custom_model=load_custom_model)
# Putting model to device and setting eval mode
model.to(device)
model.train()
# Freeze the backbone parameters, if needed
if backbone is not None and model_cfg['freeze_backbone']:
for param in backbone.parameters():
param.requires_grad = False
print('Backbone is freezed!')
#####################################
# Creating datasets and dataloaders
#####################################
data_root = data_cfg['root']
################################
# Creating training datasets and dataloaders
print("Loading training data")
train_datasets_names = data_cfg['train']
if train_cfg['mixed_batch']:
assert train_cfg['tgt_images_in_batch'] > 0, \
"Using mixed training. You need to specify the tgt_images_in_batch parameter!"
assert len(train_datasets_names) == 2, "Using mixed training, you need to specify two datasets, " \
"the first one as the source while the second as the target"
source_dataset = CustomYoloAnnotatedDataset(
data_root, {
list(train_datasets_names.keys())[0]:
list(train_datasets_names.values())[0]
},
transforms=get_transform(train=True),
phase='train')
target_dataset = CustomYoloAnnotatedDataset(
data_root, {
list(train_datasets_names.keys())[1]:
list(train_datasets_names.values())[1]
},
transforms=get_transform(train=True),
phase='train')
train_dataset = DatasetsEnsemble(source_dataset=source_dataset,
target_dataset=target_dataset)
train_dataloader = DataLoader(
train_dataset,
collate_fn=train_dataset.source_dataset.standard_collate_fn,
num_workers=train_cfg['num_workers'],
batch_sampler=EnsembleBatchSampler(
train_dataset,
batch_size=train_cfg['batch_size'],
shuffle=True,
tgt_imgs_in_batch=train_cfg['tgt_images_in_batch']))
print(
'Using mixed training datasets. Source: {}, Target: {}. In every batch, {}/{} are from {}'
.format(
list(train_datasets_names.keys())[0],
list(train_datasets_names.keys())[1],
train_cfg['tgt_images_in_batch'], train_cfg['batch_size'],
list(train_datasets_names.keys())[1]))
else:
train_dataset = CustomYoloAnnotatedDataset(
data_root,
train_datasets_names,
transforms=get_transform(train=True),
phase='train')
train_dataloader = DataLoader(
train_dataset,
batch_size=train_cfg['batch_size'],
shuffle=False,
num_workers=train_cfg['num_workers'],
collate_fn=train_dataset.standard_collate_fn)
###############################
# Creating validation datasets
print("Loading validation data")
val_datasets_names = data_cfg['val']
# Creating dataset(s) and dataloader(s)
val_dataloaders = dict()
best_validation_ap = defaultdict(float)
for dataset_name, dataset_cfg in val_datasets_names.items():
val_dataset = CustomYoloAnnotatedDataset(
data_root, {dataset_name: dataset_cfg},
transforms=get_transform(),
phase="val",
percentage=train_cfg["percentage_val"])
val_dataloader = DataLoader(val_dataset,
batch_size=train_cfg['batch_size'],
shuffle=False,
num_workers=train_cfg['num_workers'],
collate_fn=val_dataset.standard_collate_fn)
# Adding created dataloader
val_dataloaders[dataset_name] = val_dataloader
# Initializing best validation ap value
best_validation_ap[dataset_name] = 0.0
#######################################
# Defining optimizer and LR scheduler
#######################################
##########################
# Constructing an optimizer
params = [p for p in model.parameters() if p.requires_grad]
optimizer = torch.optim.SGD(
params,
lr=train_cfg['lr'],
momentum=train_cfg['momentum'],
weight_decay=train_cfg['weight_decay'],
)
# and a learning rate scheduler
if model_cfg['coco_model_pretrained']:
lr_step_size = min(25000, len(train_dataset))
else:
lr_step_size = min(40000, 2 * len(train_dataset))
lr_scheduler = torch.optim.lr_scheduler.StepLR(optimizer,
step_size=lr_step_size,
gamma=train_cfg['lr_gamma'])
# Defining a warm-up lr scheduler
warmup_iters = min(1000, len(train_dataloader) - 1)
warmup_factor = 1. / 1000
warmup_lr_scheduler = utils.warmup_lr_scheduler(optimizer, warmup_iters,
warmup_factor)
#############################
# Resuming a model
#############################
start_epoch = 0
train_step = -1
# Eventually resuming a pre-trained model
if train_cfg['pretrained_model']:
print("Resuming pre-trained model")
if train_cfg['pretrained_model'].startswith('http://') or train_cfg[
'pretrained_model'].startswith('https://'):
pre_trained_model = torch.hub.load_state_dict_from_url(
train_cfg['pretrained_model'],
map_location='cpu',
model_dir=model_cfg["cache_folder"])
else:
pre_trained_model = torch.load(train_cfg['pretrained_model'],
map_location='cpu')
model.load_state_dict(pre_trained_model['model'])
# Eventually resuming from a saved checkpoint
if train_cfg['checkpoint']:
print("Resuming from a checkpoint")
checkpoint = torch.load(train_cfg['checkpoint'])
model.load_state_dict(checkpoint['model'])
optimizer.load_state_dict(checkpoint['optimizer'])
lr_scheduler.load_state_dict(checkpoint['lr_scheduler'])
warmup_lr_scheduler.load_state_dict(checkpoint['warmup_lr_scheduler'])
start_epoch = checkpoint['epoch']
train_step = checkpoint['iteration']
for elem_name, elem in checkpoint.items():
if elem_name.startswith("best_"):
d_name = elem_name.split("_")[1]
if d_name in best_validation_ap:
best_validation_ap[d_name] = elem
else:
warnings.warn(
"The dataset {} was not used in the previous training".
format(d_name))
best_validation_ap[d_name] = 0.0
################
################
# Training
print("Start training")
for epoch in range(start_epoch, train_cfg['epochs']):
model.train()
metric_logger = utils.MetricLogger(delimiter=" ")
metric_logger.add_meter(
'lr', utils.SmoothedValue(window_size=1, fmt='{value:.6f}'))
header = 'Epoch: [{}]'.format(epoch)
for images, targets in metric_logger.log_every(
train_dataloader,
print_freq=train_cfg['print_freq'],
header=header):
train_step += 1
images = list(image.to(device) for image in images)
targets = [{k: v.to(device)
for k, v in t.items()} for t in targets]
loss_dict = model(images, targets)
losses = sum(loss for loss in loss_dict.values())
# reduce losses over all GPUs for logging purposes
loss_dict_reduced = utils.reduce_dict(loss_dict)
losses_reduced = sum(loss for loss in loss_dict_reduced.values())
loss_value = losses_reduced.item()
if not math.isfinite(loss_value):
for target in targets:
image_id = target['image_id'].item()
print(train_dataset.images[image_id])
print("Loss is {}, stopping training".format(loss_value))
print(loss_dict_reduced)
sys.exit(1)
optimizer.zero_grad()
losses.backward()
# clip norm
torch.nn.utils.clip_grad_norm_(model.parameters(), 50)
optimizer.step()
if epoch == 0 and train_step < warmup_iters:
warmup_lr_scheduler.step()
metric_logger.update(loss=losses_reduced, **loss_dict_reduced)
metric_logger.update(lr=optimizer.param_groups[0]["lr"])
if train_step % train_cfg['log_loss'] == 0:
writer.add_scalar('Training/Learning Rate',
optimizer.param_groups[0]["lr"], train_step)
writer.add_scalar('Training/Reduced Sum Losses',
losses_reduced, train_step)
writer.add_scalars('Training/All Losses', loss_dict,
train_step)
if (train_step % train_cfg['save_freq'] == 0 and train_step != 0) \
or ((train_cfg['pretrained_model'] or model_cfg['coco_model_pretrained']) and
train_step < 6 * train_cfg['save_freq'] and train_step % 200 == 0 and train_step != 0):
# Validation
for val_name, val_dataloader in val_dataloaders.items():
print("Validation on {}".format(val_name))
coco_evaluator = evaluate(
model,
val_dataloader,
device=device,
max_dets=model_cfg["max_dets_per_image"])
ap = None
for iou_type, coco_eval in coco_evaluator.coco_eval.items(
):
ap = coco_eval.stats[1]
writer.add_scalar(
'COCO mAP Validation/{}'.format(val_name), ap,
train_step)
# Eventually saving best model
if ap > best_validation_ap[val_name]:
best_validation_ap[val_name] = ap
save_checkpoint(
{
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'best_{}_ap'.format(val_name):
best_validation_ap[val_name],
},
writer.get_logdir(),
best_model=val_name)
# Saving last model
checkpoint_dict = {
'model':
model.state_dict(),
'optimizer':
optimizer.state_dict(),
'lr_scheduler':
lr_scheduler.state_dict(),
'warmup_lr_scheduler':
warmup_lr_scheduler.state_dict()
if warmup_lr_scheduler is not None else None,
'epoch':
epoch,
'iteration':
train_step,
'tensorboard_working_dir':
writer.get_logdir(),
}
for d_name, _ in val_dataloaders.items():
checkpoint_dict["best_{}_ap".format(
d_name)] = best_validation_ap[d_name]
save_checkpoint(checkpoint_dict, writer.get_logdir())
# Setting again to train mode
model.train()
# Updating lr scheduler
lr_scheduler.step()