Пример #1
0
def freezenet(net, freeze_base_net, freeze_net):
    if freeze_base_net:
        logging.info("Freeze base net.")
        freeze_net_layers(net.base_net)
        params = itertools.chain(net.source_layer_add_ons.parameters(),
                                 net.extras.parameters(),
                                 net.regression_headers.parameters(),
                                 net.classification_headers.parameters())
        params = [{
            'params':
            itertools.chain(net.source_layer_add_ons.parameters(),
                            net.extras.parameters()),
            'lr':
            extra_layers_lr
        }, {
            'params':
            itertools.chain(net.regression_headers.parameters(),
                            net.classification_headers.parameters())
        }]
    elif freeze_net:
        freeze_net_layers(net.base_net)
        freeze_net_layers(net.source_layer_add_ons)
        freeze_net_layers(net.extras)
        params = itertools.chain(net.regression_headers.parameters(),
                                 net.classification_headers.parameters())
        logging.info("Freeze all the layers except prediction heads.")
    else:
        params = [{
            'params': net.base_net.parameters(),
            'lr': base_net_lr
        }, {
            'params':
            itertools.chain(net.source_layer_add_ons.parameters(),
                            net.extras.parameters()),
            'lr':
            extra_layers_lr
        }, {
            'params':
            itertools.chain(net.regression_headers.parameters(),
                            net.classification_headers.parameters())
        }]
        return net, params
Пример #2
0
    logging.info(val_dataset)
    logging.info("validation dataset size: {}".format(len(val_dataset)))

    val_loader = DataLoader(val_dataset, args.batch_size,
                            num_workers=args.num_workers,
                            shuffle=False)
    logging.info("Build network.")
    net = create_net(num_classes)
    min_loss = -10000.0
    last_epoch = args.last_epoch-1

    base_net_lr = args.base_net_lr if args.base_net_lr is not None else args.lr
    extra_layers_lr = args.extra_layers_lr if args.extra_layers_lr is not None else args.lr
    if args.freeze_base_net:
        logging.info("Freeze base net.")
        freeze_net_layers(net.base_net)
        params = [
            {'params': itertools.chain(
                net.regression_headers.parameters(),
                net.classification_headers.parameters(),
                net.extra_layers.parameters()
            )}
        ]
    elif args.freeze_net:
        freeze_net_layers(net.base_net)
        freeze_net_layers(net.extra_layers)
        params = itertools.chain(net.regression_headers.parameters(), net.classification_headers.parameters())
        logging.info("Freeze all the layers except prediction heads.")
    else:
        params = [
            {'params': net.base_net.parameters(), 'lr': base_net_lr},
Пример #3
0
    logging.info("validation dataset size: {}".format(len(val_dataset)))

    val_loader = DataLoader(val_dataset,
                            args.batch_size,
                            num_workers=args.num_workers,
                            shuffle=False)
    logging.info("Build network.")
    net = create_net(num_classes)
    min_loss = -10000.0
    last_epoch = -1

    base_net_lr = args.base_net_lr if args.base_net_lr is not None else args.lr
    extra_layers_lr = args.extra_layers_lr if args.extra_layers_lr is not None else args.lr
    if args.freeze_base_net:
        logging.info("Freeze base net.")
        freeze_net_layers(net.base_net)
        params = itertools.chain(net.source_layer_add_ons.parameters(),
                                 net.extras.parameters(),
                                 net.regression_headers.parameters(),
                                 net.classification_headers.parameters())
        params = [{
            'params':
            itertools.chain(net.source_layer_add_ons.parameters(),
                            net.extras.parameters()),
            'lr':
            extra_layers_lr
        }, {
            'params':
            itertools.chain(net.regression_headers.parameters(),
                            net.classification_headers.parameters())
        }]
Пример #4
0
def optim_and_model_initial(args, net, timer, config, DEVICE):
    #net = create_net(num_classes)
    last_epoch = -1

    base_net_lr = args['Training_hyperparam']['base_net_lr'] if args[
        'Training_hyperparam']['base_net_lr'] != "None" else args[
            'Training_hyperparam']['lr']
    extra_layers_lr = args['Training_hyperparam']['extra_layers_lr'] if args[
        'Training_hyperparam']['extra_layers_lr'] != "None" else args[
            'Training_hyperparam']['lr']
    if args['flow_control']['freeze_base_net']:
        logging.info("Freeze base net.")
        freeze_net_layers(net.base_net)
        params = itertools.chain(net.source_layer_add_ons.parameters(),
                                 net.extras.parameters(),
                                 net.regression_headers.parameters(),
                                 net.classification_headers.parameters())
        params = [{
            'params':
            itertools.chain(net.source_layer_add_ons.parameters(),
                            net.extras.parameters()),
            'lr':
            extra_layers_lr
        }, {
            'params':
            itertools.chain(net.regression_headers.parameters(),
                            net.classification_headers.parameters())
        }]
    elif args['flow_control']['freeze_net']:
        freeze_net_layers(net.base_net)
        freeze_net_layers(net.source_layer_add_ons)
        freeze_net_layers(net.extras)
        params = itertools.chain(net.regression_headers.parameters(),
                                 net.classification_headers.parameters())
        logging.info("Freeze all the layers except prediction heads.")
    else:
        params = [{
            'params': net.base_net.parameters(),
            'lr': base_net_lr
        }, {
            'params':
            itertools.chain(net.source_layer_add_ons.parameters(),
                            net.extras.parameters()),
            'lr':
            extra_layers_lr
        }, {
            'params':
            itertools.chain(net.regression_headers.parameters(),
                            net.classification_headers.parameters())
        }]

    timer.start("Load Model")

    if args['flow_control']['resume']:
        logging.info("Resume from the model {}".format(
            args['flow_control']['resume']))
        net.load(args['flow_control']['resume'])
    elif args['flow_control']['base_net']:
        logging.info("Init from base net {}".format(
            args['flow_control']['base_net']))
        net.init_from_base_net(args['flow_control']['base_net'])
    elif args['flow_control']['pretrained_ssd']:
        logging.info("Init from pretrained ssd {}".format(
            args['flow_control']['pretrained_ssd']))
        net.init_from_pretrained_ssd(args['flow_control']['pretrained_ssd'])
    logging.info('Took {:.2f} seconds to load the model.'.format(
        timer.end("Load Model")))

    # net.to(DEVICE)
    net = nn.DataParallel(net).cuda()
    neg_pos_ratio = 3  #3

    criterion = MultiboxLoss(config.priors,
                             iou_threshold=0.5,
                             neg_pos_ratio=neg_pos_ratio,
                             center_variance=0.1,
                             size_variance=0.2,
                             device=DEVICE)
    # criterion = MultiboxLoss(config.priors, iou_threshold=0.5, neg_pos_ratio=1,
    #                          center_variance=0.1, size_variance=0.2, device=DEVICE)
    optimizer = torch.optim.SGD(
        params,
        lr=args['Training_hyperparam']['lr'],
        momentum=args['Training_hyperparam']['momentum'],
        weight_decay=args['Training_hyperparam']['weighted_decay'])
    logging.info("Learning rate: {}, Base net learning rate: {}, ".format(
        args['Training_hyperparam']['lr'], base_net_lr) +
                 "Extra Layers learning rate: {}.".format(extra_layers_lr))

    if args['Training_hyperparam']['lr_scheduler'] == 'multi-step':
        logging.info("Uses MultiStepLR scheduler.")
        milestones = [
            int(v.strip()) for v in args["Training_hyperparam"]
            ["lr_scheduler_param"]["multi-step"]['milestones'].split(",")
        ]
        scheduler = MultiStepLR(optimizer,
                                milestones=milestones,
                                gamma=args["Training_hyperparam"]
                                ["lr_scheduler_param"]["multi-step"]['gamma'],
                                last_epoch=last_epoch)
    elif args['Training_hyperparam']['lr_scheduler'] == 'cosine':
        logging.info("Uses CosineAnnealingLR scheduler.")
        scheduler = CosineAnnealingLR(
            optimizer,
            float(args['Training_hyperparam']['lr_scheduler_param']['cosine']
                  ['t_max']),
            last_epoch=last_epoch)
    else:
        logging.fatal("Unsupported Scheduler: {}.".format(
            args['Training_hyperparam']['lr_scheduler']))
        parser.print_help(sys.stderr)
        sys.exit(1)

    logging.info("Start training from epoch {}.".format(last_epoch + 1))

    return net, criterion, optimizer, scheduler
                                    dataset_type="test")
    log.info(val_dataset)
    log.info("validation dataset size: {}".format(len(val_dataset)))

    val_loader = DataLoader(val_dataset,
                            args.batch_size,
                            num_workers=args.num_workers,
                            shuffle=False)
    log.info("Build network.")
    net = create_net(num_classes)
    min_loss = -10000.0
    last_epoch = -1

    # freeze_base_net:
    log.info("Freeze base net..")
    freeze_net_layers(net.base_net)
    params = itertools.chain(net.source_layer_add_ons.parameters(),
                             net.extras.parameters(),
                             net.regression_headers.parameters(),
                             net.classification_headers.parameters())
    # log.info("params 1 = "+str(params))
    params = [{
        'params':
        itertools.chain(net.source_layer_add_ons.parameters(),
                        net.extras.parameters()),
        'lr':
        args.extra_layers_lr
    }, {
        'params':
        itertools.chain(net.regression_headers.parameters(),
                        net.classification_headers.parameters())
Пример #6
0
def main(args):
    DEVICE = torch.device(
        "cuda:0" if torch.cuda.is_available() and args.use_cuda else "cpu")
    #DEVICE = torch.device("cpu")
    if args.use_cuda and torch.cuda.is_available():
        torch.backends.cudnn.benchmark = True
        logging.info("Use Cuda.")

    timer = Timer()

    logging.info(args)
    if args.net == 'vgg16-ssd':
        create_net = create_vgg_ssd
        config = vgg_ssd_config
    elif args.net == 'mb1-ssd':
        create_net = create_mobilenetv1_ssd
        config = mobilenetv1_ssd_config
    elif args.net == 'mb1-ssd-lite':
        create_net = create_mobilenetv1_ssd_lite
        config = mobilenetv1_ssd_config
    elif args.net == 'sq-ssd-lite':
        create_net = create_squeezenet_ssd_lite
        config = squeezenet_ssd_config
    elif args.net == 'mb2-ssd-lite':
        create_net = lambda num: create_mobilenetv2_ssd_lite(
            num, width_mult=args.mb2_width_mult)
        config = mobilenetv1_ssd_config
    else:
        logging.fatal("The net type is wrong.")
        parser.print_help(sys.stderr)
        sys.exit(1)
    train_transform = TrainAugmentation(config.image_size, config.image_mean,
                                        config.image_std)
    target_transform = MatchPrior(config.priors, config.center_variance,
                                  config.size_variance, 0.5)

    test_transform = TestTransform(config.image_size, config.image_mean,
                                   config.image_std)

    logging.info("Prepare training datasets.")
    datasets = []
    for dataset_path in args.datasets:
        if args.dataset_type == 'voc':
            dataset = VOCDataset(dataset_path,
                                 transform=train_transform,
                                 target_transform=target_transform)
            label_file = os.path.join(args.checkpoint_folder,
                                      "voc-model-labels.txt")
            store_labels(label_file, dataset.class_names)
            num_classes = len(dataset.class_names)
        elif args.dataset_type == 'open_images':
            dataset = OpenImagesDataset(dataset_path,
                                        transform=train_transform,
                                        target_transform=target_transform,
                                        dataset_type="train",
                                        balance_data=args.balance_data)
            label_file = os.path.join(args.checkpoint_folder,
                                      "open-images-model-labels.txt")
            store_labels(label_file, dataset.class_names)
            logging.info(dataset)
            num_classes = len(dataset.class_names)
        elif args.dataset_type == 'coco':
            # root, annFile, transform=None, target_transform=None, transforms=None)
            #  dataset_type="train", balance_data=args.balance_data)
            dataset = CocoDetection(
                "/home/wenyen4desh/datasets/coco/train2017",
                "/home/wenyen4desh/datasets/coco/annotations/instances_train2017.json",
                transform=train_transform,
                target_transform=target_transform)

            label_file = os.path.join(args.checkpoint_folder,
                                      "open-images-model-labels.txt")
            store_labels(label_file, dataset.class_names)
            logging.info(dataset)
            num_classes = len(dataset.class_names)
            # raise ValueError("Dataset type {} yet implement.".format(args.dataset_type))
        else:
            raise ValueError("Dataset type {} is not supported.".format(
                args.dataset_type))
        datasets.append(dataset)
    logging.info("Stored labels into file {}.".format(label_file))
    train_dataset = ConcatDataset(datasets)
    logging.info("Train dataset size: {}".format(len(train_dataset)))
    train_loader = DataLoader(train_dataset,
                              args.batch_size,
                              num_workers=args.num_workers,
                              shuffle=True)
    logging.info("Prepare Validation datasets.")
    if args.dataset_type == "voc":
        val_dataset = VOCDataset(args.validation_dataset,
                                 transform=test_transform,
                                 target_transform=target_transform,
                                 is_test=True)
    elif args.dataset_type == 'open_images':
        val_dataset = OpenImagesDataset(dataset_path,
                                        transform=test_transform,
                                        target_transform=target_transform,
                                        dataset_type="test")
        logging.info(val_dataset)
    elif args.dataset_type == "coco":
        val_dataset = CocoDetection(
            "/home/wenyen4desh/datasets/coco/val2017",
            "/home/wenyen4desh/datasets/coco/annotations/instances_val2017.json",
            transform=test_transform,
            target_transform=target_transform)
        logging.info(val_dataset)
    logging.info("validation dataset size: {}".format(len(val_dataset)))

    val_loader = DataLoader(val_dataset,
                            args.batch_size,
                            num_workers=args.num_workers,
                            shuffle=False)
    logging.info("Build network.")
    net = create_net(num_classes)
    min_loss = -10000.0
    last_epoch = -1

    base_net_lr = args.base_net_lr if args.base_net_lr is not None else args.lr
    extra_layers_lr = args.extra_layers_lr if args.extra_layers_lr is not None else args.lr
    if args.freeze_base_net:
        logging.info("Freeze base net.")
        freeze_net_layers(net.base_net)
        params = itertools.chain(net.source_layer_add_ons.parameters(),
                                 net.extras.parameters(),
                                 net.regression_headers.parameters(),
                                 net.classification_headers.parameters())
        params = [{
            'params':
            itertools.chain(net.source_layer_add_ons.parameters(),
                            net.extras.parameters()),
            'lr':
            extra_layers_lr
        }, {
            'params':
            itertools.chain(net.regression_headers.parameters(),
                            net.classification_headers.parameters())
        }]
    elif args.freeze_net:
        freeze_net_layers(net.base_net)
        freeze_net_layers(net.source_layer_add_ons)
        freeze_net_layers(net.extras)
        params = itertools.chain(net.regression_headers.parameters(),
                                 net.classification_headers.parameters())
        logging.info("Freeze all the layers except prediction heads.")
    else:
        params = [{
            'params': net.base_net.parameters(),
            'lr': base_net_lr
        }, {
            'params':
            itertools.chain(net.source_layer_add_ons.parameters(),
                            net.extras.parameters()),
            'lr':
            extra_layers_lr
        }, {
            'params':
            itertools.chain(net.regression_headers.parameters(),
                            net.classification_headers.parameters())
        }]

    timer.start("Load Model")
    if args.resume:
        logging.info("Resume from the model {}".format(args.resume))
        net.load(args.resume)
    elif args.base_net:
        logging.info("Init from base net {}".format(args.base_net))
        net.init_from_base_net(args.base_net)
    elif args.pretrained_ssd:
        logging.info("Init from pretrained ssd {}".format(args.pretrained_ssd))
        net.init_from_pretrained_ssd(args.pretrained_ssd)
    logging.info('Took {:.2f} seconds to load the model.'.format(
        timer.end("Load Model")))

    net.to(DEVICE)

    criterion = MultiboxLoss(config.priors,
                             iou_threshold=0.5,
                             neg_pos_ratio=3,
                             center_variance=0.1,
                             size_variance=0.2,
                             device=DEVICE)
    optimizer = torch.optim.SGD(params,
                                lr=args.lr,
                                momentum=args.momentum,
                                weight_decay=args.weight_decay)
    logging.info("Learning rate: {}, Base net learning rate: {}, ".format(
        args.lr, base_net_lr) +
                 "Extra Layers learning rate: {}.".format(extra_layers_lr))

    if args.scheduler == 'multi-step':
        logging.info("Uses MultiStepLR scheduler.")
        milestones = [int(v.strip()) for v in args.milestones.split(",")]
        scheduler = MultiStepLR(optimizer,
                                milestones=milestones,
                                gamma=0.1,
                                last_epoch=last_epoch)
    elif args.scheduler == 'cosine':
        logging.info("Uses CosineAnnealingLR scheduler.")
        scheduler = CosineAnnealingLR(optimizer,
                                      args.t_max,
                                      last_epoch=last_epoch)
    else:
        logging.fatal("Unsupported Scheduler: {}.".format(args.scheduler))
        parser.print_help(sys.stderr)
        sys.exit(1)

    logging.info("Start training from epoch {}.".format(last_epoch + 1))
    for epoch in range(last_epoch + 1, args.num_epochs):
        scheduler.step()
        train(train_loader,
              net,
              criterion,
              optimizer,
              device=DEVICE,
              debug_steps=args.debug_steps,
              epoch=epoch)

        if epoch % args.validation_epochs == 0 or epoch == args.num_epochs - 1:
            val_loss, val_regression_loss, val_classification_loss = test(
                val_loader, net, criterion, DEVICE)
            logging.info("Epoch: {}, ".format(epoch) +
                         "Validation Loss: {:.4f}, ".format(val_loss) +
                         "Validation Regression Loss {:.4f}, ".format(
                             val_regression_loss) +
                         "Validation Classification Loss: {:.4f}".format(
                             val_classification_loss))
            model_path = os.path.join(
                args.checkpoint_folder,
                "{}-Epoch-{}-Loss-{}.pth".format(args.net, epoch, val_loss))
            net.save(model_path)
            logging.info("Saved model {}".format(model_path))
Пример #7
0
    def setup_and_start_training(self):
        logging.basicConfig(
            stream=sys.stdout,
            level=logging.INFO,
            format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')

        DEVICE = torch.device("cuda:0" if torch.cuda.is_available() and self.
                              system_dict["params"]["use_cuda"] else "cpu")

        if self.system_dict["params"]["use_cuda"] and torch.cuda.is_available(
        ):
            torch.backends.cudnn.benchmark = True
            logging.info("Using gpu.")
        else:
            logging.info("Using cpu.")

        timer = Timer()
        logging.info(self.system_dict)

        if self.system_dict["params"]["net"] == 'vgg16-ssd':
            create_net = create_vgg_ssd
            config = vgg_ssd_config
        elif self.system_dict["params"]["net"] == 'mb1-ssd':
            create_net = create_mobilenetv1_ssd
            config = mobilenetv1_ssd_config
        elif self.system_dict["params"]["net"] == 'mb1-ssd-lite':
            create_net = create_mobilenetv1_ssd_lite
            config = mobilenetv1_ssd_config
        elif self.system_dict["params"]["net"] == 'sq-ssd-lite':
            create_net = create_squeezenet_ssd_lite
            config = squeezenet_ssd_config
        elif self.system_dict["params"]["net"] == 'mb2-ssd-lite':
            create_net = lambda num: create_mobilenetv2_ssd_lite(
                num, width_mult=self.system_dict["params"]["mb2_width_mult"])
            config = mobilenetv1_ssd_config
        else:
            logging.fatal("The net type is wrong.")
            sys.exit(1)

        train_transform = TrainAugmentation(config.image_size,
                                            config.image_mean,
                                            config.image_std)
        target_transform = MatchPrior(config.priors, config.center_variance,
                                      config.size_variance, 0.5)

        test_transform = TestTransform(config.image_size, config.image_mean,
                                       config.image_std)

        logging.info("Prepare training datasets.")
        datasets = []
        dataset = VOCDataset(
            self.system_dict["dataset"]["val"]["img_dir"],
            self.system_dict["dataset"]["val"]["label_dir"],
            transform=train_transform,
            target_transform=target_transform,
            label_file=self.system_dict["params"]["label_file"])
        label_file = self.system_dict["params"]["label_file"]
        #store_labels(label_file, dataset.class_names)
        num_classes = len(dataset.class_names)
        datasets.append(dataset)
        logging.info(f"Stored labels into file {label_file}.")
        train_dataset = ConcatDataset(datasets)
        logging.info("Train dataset size: {}".format(len(train_dataset)))
        train_loader = DataLoader(
            train_dataset,
            self.system_dict["params"]["batch_size"],
            num_workers=self.system_dict["params"]["num_workers"],
            shuffle=True)

        if (self.system_dict["dataset"]["val"]["status"]):
            val_dataset = VOCDataset(
                self.system_dict["dataset"]["val"]["img_dir"],
                self.system_dict["dataset"]["val"]["label_dir"],
                transform=test_transform,
                target_transform=target_transform,
                is_test=True,
                label_file=self.system_dict["params"]["label_file"])
            logging.info("validation dataset size: {}".format(
                len(val_dataset)))
            val_loader = DataLoader(
                val_dataset,
                self.system_dict["params"]["batch_size"],
                num_workers=self.system_dict["params"]["num_workers"],
                shuffle=False)

        logging.info("Build network.")
        net = create_net(num_classes)
        min_loss = -10000.0
        last_epoch = -1

        base_net_lr = self.system_dict["params"][
            "base_net_lr"] if self.system_dict["params"][
                "base_net_lr"] is not None else self.system_dict["params"]["lr"]
        extra_layers_lr = self.system_dict["params"][
            "extra_layers_lr"] if self.system_dict["params"][
                "extra_layers_lr"] is not None else self.system_dict["params"][
                    "lr"]

        if self.system_dict["params"]["freeze_base_net"]:
            logging.info("Freeze base net.")
            freeze_net_layers(net.base_net)
            params = itertools.chain(net.source_layer_add_ons.parameters(),
                                     net.extras.parameters(),
                                     net.regression_headers.parameters(),
                                     net.classification_headers.parameters())
            params = [{
                'params':
                itertools.chain(net.source_layer_add_ons.parameters(),
                                net.extras.parameters()),
                'lr':
                extra_layers_lr
            }, {
                'params':
                itertools.chain(net.regression_headers.parameters(),
                                net.classification_headers.parameters())
            }]
        elif self.system_dict["params"]["freeze_net"]:
            freeze_net_layers(net.base_net)
            freeze_net_layers(net.source_layer_add_ons)
            freeze_net_layers(net.extras)
            params = itertools.chain(net.regression_headers.parameters(),
                                     net.classification_headers.parameters())
            logging.info("Freeze all the layers except prediction heads.")
        else:
            params = [{
                'params': net.base_net.parameters(),
                'lr': base_net_lr
            }, {
                'params':
                itertools.chain(net.source_layer_add_ons.parameters(),
                                net.extras.parameters()),
                'lr':
                extra_layers_lr
            }, {
                'params':
                itertools.chain(net.regression_headers.parameters(),
                                net.classification_headers.parameters())
            }]

        timer.start("Load Model")
        resume = self.system_dict["params"]["resume"]
        base_net = self.system_dict["params"]["base_net"]
        pretrained_ssd = self.system_dict["params"]["pretrained_ssd"]
        if self.system_dict["params"]["resume"]:
            logging.info(f"Resume from the model {resume}")
            net.load(self.system_dict["params"]["resume"])
        elif self.system_dict["params"]["base_net"]:
            logging.info(f"Init from base net {base_net}")
            net.init_from_base_net(self.system_dict["params"]["base_net"])
        elif self.system_dict["params"]["pretrained_ssd"]:
            logging.info(f"Init from pretrained ssd {pretrained_ssd}")
            net.init_from_pretrained_ssd(
                self.system_dict["params"]["pretrained_ssd"])
        logging.info(
            f'Took {timer.end("Load Model"):.2f} seconds to load the model.')

        net.to(DEVICE)

        criterion = MultiboxLoss(config.priors,
                                 iou_threshold=0.5,
                                 neg_pos_ratio=3,
                                 center_variance=0.1,
                                 size_variance=0.2,
                                 device=DEVICE)
        optimizer = torch.optim.SGD(
            params,
            lr=self.system_dict["params"]["lr"],
            momentum=self.system_dict["params"]["momentum"],
            weight_decay=self.system_dict["params"]["weight_decay"])
        lr = self.system_dict["params"]["lr"]
        logging.info(
            f"Learning rate: {lr}, Base net learning rate: {base_net_lr}, " +
            f"Extra Layers learning rate: {extra_layers_lr}.")

        if (not self.system_dict["params"]["milestones"]):
            self.system_dict["params"]["milestones"] = ""
            self.system_dict["params"]["milestones"] += str(
                int(self.system_dict["params"]["num_epochs"] / 3)) + ","
            self.system_dict["params"]["milestones"] += str(
                int(2 * self.system_dict["params"]["num_epochs"] / 3))

        if self.system_dict["params"]["scheduler"] == 'multi-step':
            logging.info("Uses MultiStepLR scheduler.")
            milestones = [
                int(v.strip())
                for v in self.system_dict["params"]["milestones"].split(",")
            ]
            scheduler = MultiStepLR(optimizer,
                                    milestones=milestones,
                                    gamma=0.1,
                                    last_epoch=last_epoch)
        elif self.system_dict["params"]["scheduler"] == 'cosine':
            logging.info("Uses CosineAnnealingLR scheduler.")
            scheduler = CosineAnnealingLR(optimizer,
                                          self.system_dict["params"]["t_max"],
                                          last_epoch=last_epoch)

        logging.info(f"Start training from epoch {last_epoch + 1}.")
        for epoch in range(last_epoch + 1,
                           self.system_dict["params"]["num_epochs"]):
            scheduler.step()
            self.base_train(
                train_loader,
                net,
                criterion,
                optimizer,
                device=DEVICE,
                debug_steps=self.system_dict["params"]["debug_steps"],
                epoch=epoch)

            if ((self.system_dict["dataset"]["val"]["status"]) and
                (epoch % self.system_dict["params"]["validation_epochs"] == 0
                 or epoch == self.system_dict["params"]["num_epochs"] - 1)):
                val_loss, val_regression_loss, val_classification_loss = self.base_test(
                    val_loader, net, criterion, DEVICE)
                logging.info(
                    f"Epoch: {epoch}, " +
                    f"Validation Loss: {val_loss:.4f}, " +
                    f"Validation Regression Loss {val_regression_loss:.4f}, " +
                    f"Validation Classification Loss: {val_classification_loss:.4f}"
                )
                net_name = self.system_dict["params"]["net"]
                model_path = os.path.join(
                    self.system_dict["params"]["checkpoint_folder"],
                    f"{net_name}-Epoch-{epoch}-Loss-{val_loss}.pth")
                net.save(model_path)
                logging.info(f"Saved model {model_path}")
            if (not self.system_dict["dataset"]["val"]["status"]):
                model_path = os.path.join(
                    self.system_dict["params"]["checkpoint_folder"],
                    f"{net_name}-Epoch-{epoch}.pth")
                net.save(model_path)
                logging.info(f"Saved model {model_path}")