Beispiel #1
0
def main(args):

    # Data
    print('==> Preparing data..')
    _size = 32
    transform_train = transforms.Compose([
        transforms.Resize(size=_size),
        transforms.RandomResizedCrop(size=_size, scale=(0.2, 1.)),
        transforms.ColorJitter(0.4, 0.4, 0.4, 0.4),
        transforms.RandomGrayscale(p=0.2),
        transforms.RandomHorizontalFlip(),
        transforms.ToTensor(),
        transforms.Normalize((0.4914, 0.4822, 0.4465),
                             (0.2023, 0.1994, 0.2010)),
    ])

    transform_test = transforms.Compose([
        transforms.Resize(size=_size),
        transforms.ToTensor(),
        transforms.Normalize((0.4914, 0.4822, 0.4465),
                             (0.2023, 0.1994, 0.2010)),
    ])

    trainset = datasets.CIFAR10Instance(root='./data',
                                        train=True,
                                        download=True,
                                        transform=transform_train)
    trainloader = torch.utils.data.DataLoader(trainset,
                                              batch_size=args.batch_size,
                                              shuffle=True,
                                              num_workers=4)

    testset = datasets.CIFAR10Instance(root='./data',
                                       train=False,
                                       download=True,
                                       transform=transform_test)
    testloader = torch.utils.data.DataLoader(testset,
                                             batch_size=100,
                                             shuffle=False,
                                             num_workers=4)

    classes = ('plane', 'car', 'bird', 'cat', 'deer', 'dog', 'frog', 'horse',
               'ship', 'truck')
    ndata = trainset.__len__()

    print('==> Building model..')
    net = models.__dict__['ResNet18'](low_dim=args.low_dim)

    device = 'cuda' if torch.cuda.is_available() else 'cpu'
    if device == 'cuda':
        net = torch.nn.DataParallel(net,
                                    device_ids=range(
                                        torch.cuda.device_count()))
        cudnn.benchmark = True

    criterion = ICRcriterion()
    # define loss function: inner product loss within each mini-batch
    uel_criterion = BatchCriterion(args.batch_m, args.batch_t, args.batch_size,
                                   ndata)

    net.to(device)
    criterion.to(device)
    uel_criterion.to(device)
    best_acc = 0  # best test accuracy
    start_epoch = 0  # start from epoch 0 or last checkpoint epoch

    if args.test_only or len(args.resume) > 0:
        # Load checkpoint.
        model_path = 'checkpoint/' + args.resume
        print('==> Resuming from checkpoint..')
        assert os.path.isdir(
            args.model_dir), 'Error: no checkpoint directory found!'
        checkpoint = torch.load(model_path)
        net.load_state_dict(checkpoint['net'])
        best_acc = checkpoint['acc']
        start_epoch = checkpoint['epoch']

    # define leminiscate
    if args.test_only and len(args.resume) > 0:

        trainFeatures, feature_index = compute_feature(trainloader, net,
                                                       len(trainset), args)
        lemniscate = LinearAverage(torch.tensor(trainFeatures), args.low_dim,
                                   ndata, args.nce_t, args.nce_m)

    else:

        lemniscate = LinearAverage(torch.tensor([]), args.low_dim, ndata,
                                   args.nce_t, args.nce_m)
    lemniscate.to(device)

    # define optimizer
    optimizer = torch.optim.SGD(net.parameters(),
                                lr=args.lr,
                                momentum=0.9,
                                weight_decay=5e-4)
    # optimizer2 = torch.optim.SGD(net2.parameters(), lr=args.lr, momentum=0.9, weight_decay=5e-4)

    # test acc
    if args.test_only:
        acc = kNN(0,
                  net,
                  trainloader,
                  testloader,
                  200,
                  args.batch_t,
                  ndata,
                  low_dim=args.low_dim)
        exit(0)

    if len(args.resume) > 0:
        best_acc = best_acc
        start_epoch = start_epoch + 1
    else:
        best_acc = 0  # best test accuracy
        start_epoch = 0  # start from epoch 0 or last checkpoint epoch

    icr2 = ICRDiscovery(ndata)

    # init_cluster_num = 20000
    for round in range(5):
        for epoch in range(start_epoch, 200):
            #### get Features

            # trainFeatures are trainloader features and shuffle=True, so feature_index is match data
            trainFeatures, feature_index = compute_feature(
                trainloader, net, len(trainset), args)

            if round == 0:
                y = -1 * math.log10(ndata) / 200 * epoch + math.log10(ndata)
                cluster_num = int(math.pow(10, y))
                if cluster_num <= args.nmb_cluster:
                    cluster_num = args.nmb_cluster

                print('cluster number: ' + str(cluster_num))

                ###clustering algorithm to use
                # faiss cluster
                deepcluster = clustering.__dict__[args.clustering](
                    int(cluster_num))

                #### Features to clustering
                clustering_loss = deepcluster.cluster(trainFeatures,
                                                      feature_index,
                                                      verbose=args.verbose)

                L = np.array(deepcluster.images_lists)
                image_dict = deepcluster.images_dict

                print('create ICR ...')
                # icr = ICRDiscovery(ndata)

                # if args.test_only and len(args.resume) > 0:
                # icr = cluster_assign(icr, L, trainFeatures, feature_index, trainset,
                # cluster_ratio + epoch*((1-cluster_ratio)/250))
                icrtime = time.time()

                # icr = cluster_assign(epoch, L, trainFeatures, feature_index, 1, 1)
                if epoch < args.warm_epoch:
                    icr = cluster_assign(epoch, L, trainFeatures,
                                         feature_index, args.cluster_ratio, 1)
                else:
                    icr = PreScore(epoch, L, image_dict, trainFeatures,
                                   feature_index, trainset, args.high_ratio,
                                   args.cluster_ratio, args.alpha, args.beta)

                print('calculate ICR time is: {}'.format(time.time() -
                                                         icrtime))
                writer.add_scalar('icr_time', (time.time() - icrtime),
                                  epoch + round * 200)

            else:
                cluster_num = args.nmb_cluster
                print('cluster number: ' + str(cluster_num))

                ###clustering algorithm to use
                # faiss cluster
                deepcluster = clustering.__dict__[args.clustering](
                    int(cluster_num))

                #### Features to clustering
                clustering_loss = deepcluster.cluster(trainFeatures,
                                                      feature_index,
                                                      verbose=args.verbose)

                L = np.array(deepcluster.images_lists)
                image_dict = deepcluster.images_dict

                print('create ICR ...')
                # icr = ICRDiscovery(ndata)

                # if args.test_only and len(args.resume) > 0:
                # icr = cluster_assign(icr, L, trainFeatures, feature_index, trainset,
                # cluster_ratio + epoch*((1-cluster_ratio)/250))
                icrtime = time.time()

                # icr = cluster_assign(epoch, L, trainFeatures, feature_index, 1, 1)
                icr = PreScore(epoch, L, image_dict, trainFeatures,
                               feature_index, trainset, args.high_ratio,
                               args.cluster_ratio, args.alpha, args.beta)

                print('calculate ICR time is: {}'.format(time.time() -
                                                         icrtime))
                writer.add_scalar('icr_time', (time.time() - icrtime),
                                  epoch + round * 200)

            # else:
            #     icr = cluster_assign(icr, L, trainFeatures, feature_index, trainset, 0.2 + epoch*0.004)

            # print(icr.neighbours)

            icr2 = train(epoch, net, optimizer, lemniscate, criterion,
                         uel_criterion, trainloader, icr, icr2,
                         args.stage_update, args.lr, device, round)

            print('----------Evaluation---------')
            start = time.time()
            acc = kNN(0,
                      net,
                      trainloader,
                      testloader,
                      200,
                      args.batch_t,
                      ndata,
                      low_dim=args.low_dim)
            print("Evaluation Time: '{}'s".format(time.time() - start))

            writer.add_scalar('nn_acc', acc, epoch + round * 200)

            if acc > best_acc:
                print('Saving..')
                state = {
                    'net': net.state_dict(),
                    'acc': acc,
                    'epoch': epoch,
                }
                if not os.path.isdir(args.model_dir):
                    os.mkdir(args.model_dir)
                torch.save(state,
                           './checkpoint/ckpt_best_round_{}.t7'.format(round))

                best_acc = acc

            state = {
                'net': net.state_dict(),
                'acc': acc,
                'epoch': epoch,
            }
            torch.save(state,
                       './checkpoint/ckpt_last_round_{}.t7'.format(round))

            print(
                '[Round]: {} [Epoch]: {} \t accuracy: {}% \t (best acc: {}%)'.
                format(round, epoch, acc, best_acc))
Beispiel #2
0
# define loss function
if hasattr(lemniscate, 'K'):
    criterion = NCECriterion(ndata)
else:
    criterion = nn.CrossEntropyLoss()
CE = nn.CrossEntropyLoss()

ID = InstanceDiscrimination(tau=1.0)
FD = FeatureDecorrelation(args.low_dim, tau2=2.0)

net.to(device)
lemniscate.to(device)
criterion.to(device)
ID.to(device)
FD.to(device)
LA.to(device)
CE.to(device)

if args.test_only:
    acc = kNN(0, net, lemniscate, trainloader, testloader, 200, args.nce_t, 1)
    sys.exit(0)

optimizer = optim.SGD(net.parameters(),
                      lr=args.lr,
                      momentum=0.9,
                      weight_decay=5e-4)


def adjust_learning_rate(optimizer, epoch):
    """Sets the learning rate to the initial LR decayed by 10 every 30 epochs"""
    lr = args.lr