Пример #1
0
def main(args):

    # do not track lambda param, it can be changed after train
    exp = Experiment(args, ignore=('lambda_', ))
    print(exp)

    if exp.found:
        print('Already exists: SKIPPING')
        exit(0)

    np.random.seed(args.seed)
    tf.random.set_seed(args.seed)

    # get data
    train_dataset = get_train_data(args.category,
                                   image_size=args.image_size,
                                   patch_size=args.patch_size,
                                   batch_size=args.batch_size,
                                   n_batches=args.n_batches,
                                   rotation_range=args.rotation_range,
                                   seed=args.seed)

    test_dataset, test_labels = get_test_data(args.category,
                                              image_size=args.image_size,
                                              patch_size=args.patch_size,
                                              batch_size=args.batch_size)

    is_object = args.category in objects

    # build models
    generator = make_generator(args.latent_size,
                               channels=args.channels,
                               upsample_first=is_object,
                               upsample_type=args.ge_up,
                               bn=args.ge_bn,
                               act=args.ge_act)
    encoder = make_encoder(args.patch_size,
                           args.latent_size,
                           channels=args.channels,
                           bn=args.ge_bn,
                           act=args.ge_act)
    discriminator = make_discriminator(args.patch_size,
                                       args.latent_size,
                                       channels=args.channels,
                                       bn=args.d_bn,
                                       act=args.d_act)
    # feature extractor model for evaluation
    discriminator_features = get_discriminator_features_model(discriminator)

    # build optimizers
    generator_encoder_optimizer = O.Adam(args.lr,
                                         beta_1=args.ge_beta1,
                                         beta_2=args.ge_beta2)
    discriminator_optimizer = O.Adam(args.lr,
                                     beta_1=args.d_beta1,
                                     beta_2=args.d_beta2)

    # reference to the models to use in eval
    generator_eval = generator
    encoder_eval = encoder

    # for smoothing generator and encoder evolution
    if args.ge_decay > 0:
        ema = tf.train.ExponentialMovingAverage(decay=args.ge_decay)
        generator_ema = tf.keras.models.clone_model(generator)
        encoder_ema = tf.keras.models.clone_model(encoder)

        generator_eval = generator_ema
        encoder_eval = encoder_ema

    # checkpointer
    checkpoint = tf.train.Checkpoint(
        generator=generator,
        encoder=encoder,
        discriminator=discriminator,
        generator_encoder_optimizer=generator_encoder_optimizer,
        discriminator_optimizer=discriminator_optimizer)
    best_ckpt_path = exp.ckpt(f'ckpt_{args.category}_best')
    last_ckpt_path = exp.ckpt(f'ckpt_{args.category}_last')

    # log stuff
    log, log_file = exp.require_csv(f'log_{args.category}.csv.gz')
    metrics, metrics_file = exp.require_csv(f'metrics_{args.category}.csv')
    best_metric = 0.
    best_recon = float('inf')
    best_recon_file = exp.path_to(f'best_recon_{args.category}.png')
    last_recon_file = exp.path_to(f'last_recon_{args.category}.png')

    # animate generation during training
    n_preview = 6
    train_batch = next(iter(train_dataset))[:n_preview]
    test_batch = next(iter(test_dataset))[0][:n_preview]
    latent_batch = tf.random.normal([n_preview, args.latent_size])

    if not is_object:  # take random patches from test images
        patch_location = np.random.randint(0,
                                           args.image_size - args.patch_size,
                                           (n_preview, 2))
        test_batch = [
            x[i:i + args.patch_size, j:j + args.patch_size, :]
            for x, (i, j) in zip(test_batch, patch_location)
        ]
        test_batch = K.stack(test_batch)

    video_out = exp.path_to(f'{args.category}.mp4')
    video_options = dict(fps=30, codec='libx265',
                         quality=4)  # see imageio FFMPEG options
    video_saver = VideoSaver(train_batch, test_batch, latent_batch, video_out,
                             **video_options)
    video_saver.generate_and_save(generator, encoder)

    # train loop
    progress = tqdm(train_dataset, desc=args.category, dynamic_ncols=True)
    try:
        for step, image_batch in enumerate(progress, start=1):
            if step == 1 or args.d_iter == 0:  # only for JIT compilation (tf.function) to work
                d_train = True
                ge_train = True
            elif args.d_iter:
                n_iter = step % (abs(args.d_iter) + 1)  # can be in [0, d_iter]
                d_train = (n_iter != 0) if (args.d_iter > 0) else (
                    n_iter == 0)  # True in [1, d_iter]
                ge_train = not d_train  # True when step == d_iter + 1
            else:  # d_iter == None: dynamic adjustment
                d_train = (scores['fake_score'] > 0) or (scores['real_score'] <
                                                         0)
                ge_train = (scores['real_score'] > 0) or (scores['fake_score']
                                                          < 0)

            losses, scores = train_step(image_batch,
                                        generator,
                                        encoder,
                                        discriminator,
                                        generator_encoder_optimizer,
                                        discriminator_optimizer,
                                        d_train,
                                        ge_train,
                                        alpha=args.alpha,
                                        gp_weight=args.gp_weight)

            if (args.ge_decay > 0) and (step % 10 == 0):
                ge_vars = generator.variables + encoder.variables
                ema.apply(ge_vars)  # update exponential moving average

            # tensor to numpy
            losses = {
                n: l.numpy() if l is not None else l
                for n, l in losses.items()
            }
            scores = {
                n: s.numpy() if s is not None else s
                for n, s in scores.items()
            }

            # log step metrics
            entry = {
                'step': step,
                'timestamp': pd.to_datetime('now'),
                **losses,
                **scores
            }
            log = log.append(entry, ignore_index=True)

            if step % 100 == 0:
                if args.ge_decay > 0:
                    ge_ema_vars = generator_ema.variables + encoder_ema.variables
                    for v_ema, v in zip(ge_ema_vars, ge_vars):
                        v_ema.assign(ema.average(v))

                preview = video_saver.generate_and_save(
                    generator_eval, encoder_eval)

            if step % 1000 == 0:
                log.to_csv(log_file, index=False)
                checkpoint.write(file_prefix=last_ckpt_path)

                auc, balanced_accuracy = evaluate(generator_eval,
                                                  encoder_eval,
                                                  discriminator_features,
                                                  test_dataset,
                                                  test_labels,
                                                  patch_size=args.patch_size,
                                                  lambda_=args.lambda_)

                entry = {
                    'step': step,
                    'auc': auc,
                    'balanced_accuracy': balanced_accuracy
                }
                metrics = metrics.append(entry, ignore_index=True)
                metrics.to_csv(metrics_file, index=False)

                if auc > best_metric:
                    best_metric = auc
                    checkpoint.write(file_prefix=best_ckpt_path)

                # save last image to inspect it during training
                imageio.imwrite(last_recon_file, preview)

                recon = losses['images_reconstruction_loss']
                if recon < best_recon:
                    best_recon = recon
                    imageio.imwrite(best_recon_file, preview)

                progress.set_postfix({
                    'AUC': f'{auc:.1%}',
                    'BalAcc': f'{balanced_accuracy:.1%}',
                    'BestAUC': f'{best_metric:.1%}',
                })

    except KeyboardInterrupt:
        checkpoint.write(file_prefix=last_ckpt_path)
    finally:
        log.to_csv(log_file, index=False)
        video_saver.close()

    # score the test set
    checkpoint.read(best_ckpt_path)

    auc, balanced_accuracy = evaluate(generator,
                                      encoder,
                                      discriminator_features,
                                      test_dataset,
                                      test_labels,
                                      patch_size=args.patch_size,
                                      lambda_=args.lambda_)
    print(f'{args.category}: AUC={auc}, BalAcc={balanced_accuracy}')
Пример #2
0
def main(args):
    root = 'runs_' + args.dataset
    exp = Experiment(args,
                     root=root,
                     main='model',
                     ignore=('cuda', 'device', 'epochs', 'resume'))

    print(exp)
    if os.path.exists(exp.path_to('log')) and not args.resume:
        print('Skipping ...')
        sys.exit(0)

    train_data, test_data, in_ch, out = load_dataset(args)
    train_loader = DataLoader(train_data,
                              batch_size=args.batch_size,
                              shuffle=True)
    test_loader = DataLoader(test_data,
                             batch_size=args.batch_size,
                             shuffle=False)

    if args.model == 'odenet':
        model = ODENet(in_ch,
                       out=out,
                       n_filters=args.filters,
                       downsample=args.downsample,
                       method=args.method,
                       tol=args.tol,
                       adjoint=args.adjoint,
                       dropout=args.dropout)
    else:
        model = ResNet(in_ch,
                       out=out,
                       n_filters=args.filters,
                       downsample=args.downsample,
                       dropout=args.dropout)

    model = model.to(args.device)
    if args.optim == 'sgd':
        optimizer = SGD(model.parameters(),
                        lr=args.lr,
                        momentum=0.9,
                        weight_decay=args.wd)
    elif args.optim == 'adam':
        optimizer = Adam(model.parameters(), lr=args.lr, weight_decay=args.wd)

    # print(train_data)
    # print(test_data)
    # print(model)
    # print(optimizer)

    if args.resume:
        ckpt = torch.load(exp.ckpt('last'))
        print('Loaded: {}'.format(exp.ckpt('last')))
        model.load_state_dict(ckpt['model'])
        optimizer.load_state_dict(ckpt['optim'])
        start_epoch = ckpt['epoch'] + 1
        best_accuracy = exp.log['test_acc'].max()
        print('Resuming from epoch {}: {}'.format(start_epoch, exp.name))
    else:
        metrics = evaluate(test_loader, model, args)
        best_accuracy = metrics['test_acc']
        start_epoch = 1

    if args.lrschedule == 'fixed':
        scheduler = LambdaLR(
            optimizer,
            lr_lambda=lambda x: 1)  # no-op scheduler, just for cleaner code
    elif args.lrschedule == 'plateau':
        scheduler = ReduceLROnPlateau(optimizer,
                                      mode='max',
                                      patience=args.patience)
    elif args.lrschedule == 'cosine':
        scheduler = CosineAnnealingLR(optimizer,
                                      args.lrcycle,
                                      last_epoch=start_epoch - 2)

    progress = trange(start_epoch,
                      args.epochs + 1,
                      initial=start_epoch,
                      total=args.epochs)
    for epoch in progress:
        metrics = {'epoch': epoch}

        progress.set_postfix({'Best ACC': f'{best_accuracy:.2%}'})
        progress.set_description('TRAIN')
        train_metrics = train(train_loader, model, optimizer, args)

        progress.set_description('EVAL')
        test_metrics = evaluate(test_loader, model, args)

        is_best = test_metrics['test_acc'] > best_accuracy
        best_accuracy = max(test_metrics['test_acc'], best_accuracy)

        metrics.update(train_metrics)
        metrics.update(test_metrics)

        save_checkpoint(
            exp, {
                'epoch': epoch,
                'params': vars(args),
                'model': model.state_dict(),
                'optim': optimizer.state_dict(),
                'metrics': metrics
            }, is_best)

        exp.push_log(metrics)
        sched_args = metrics[
            'test_acc'] if args.lrschedule == 'plateau' else None
        scheduler.step(sched_args)