Пример #1
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(
        colorstr('hyperparameters: ') + ', '.join(f'{k}={v}'
                                                  for k, v in hyp.items()))
    print(
        colorstr('hyperparameters: ') + ', '.join(f'{k}={v}'
                                                  for k, v in hyp.items()))
    save_dir, epochs, batch_size, total_batch_size, weights, rank = \
        Path(opt.save_dir), opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank

    # Directories
    wdir = save_dir / 'weights'
    wdir.mkdir(parents=True, exist_ok=True)  # make dir
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    results_file = save_dir / 'results.txt'

    # Save run settings
    with open(save_dir / 'hyp.yaml', 'w') as f:
        yaml.dump(hyp, f, sort_keys=False)
    with open(save_dir / 'opt.yaml', 'w') as f:
        yaml.dump(vars(opt), f, sort_keys=False)

    shutil.copyfile(os.path.basename(__file__),
                    os.path.join(str(save_dir), os.path.basename(__file__)))
    # Configure
    plots = not opt.evolve  # create plots
    cuda = device.type != 'cpu'
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.SafeLoader)  # data dict
    is_coco = opt.data.endswith('coco.yaml')

    # Logging- Doing this before checking the dataset. Might update data_dict
    loggers = {'wandb': None}  # loggers dict
    if rank in [-1, 0]:
        opt.hyp = hyp  # add hyperparameters
        run_id = torch.load(weights).get('wandb_id') if weights.endswith(
            '.pt') and os.path.isfile(weights) else None
        wandb_logger = WandbLogger(opt,
                                   Path(opt.save_dir).stem, run_id, data_dict)
        loggers['wandb'] = wandb_logger.wandb
        data_dict = wandb_logger.data_dict
        if wandb_logger.wandb:
            weights, epochs, hyp = opt.weights, opt.epochs, opt.hyp  # WandbLogger might update weights, epochs if resuming

    nc = 1 if opt.single_cls else int(data_dict['nc'])  # number of classes
    names = ['item'] if opt.single_cls and len(
        data_dict['names']) != 1 else data_dict['names']  # class names
    assert len(names) == nc, '%g names found for nc=%g dataset in %s' % (
        len(names), nc, opt.data)  # check

    # Model
    pretrained = weights.endswith('.pt')

    if 'yolov5' in opt.cfg:
        model = V5Centernet(opt.cfg,
                            num_classes=nc,
                            pretrained=weights,
                            device=device).to(device)
    else:
        model = V5Dual(opt.cfg,
                       num_classes=nc,
                       pretrained=weights,
                       device=device).to(device)

    # model = FlexibleModel(model_config=opt.cfg).to(device)

    if pretrained:
        # weights = torch.load(pretrained)
        # self.model.load_state_dict(weights)
        exclude = []  # exclude keys
        ckpt = torch.load(weights, map_location=device)  # load checkpoint
        state_dict = ckpt['model'].float().state_dict()  # to FP32
        state_dict = intersect_dicts(state_dict,
                                     model.state_dict(),
                                     exclude=exclude)  # intersect
        model.load_state_dict(state_dict, strict=False)  # load
        print('Transferred %g/%g items from %s' %
              (len(state_dict), len(model.state_dict()), weights))  # report

        del ckpt, state_dict

    # segLoss = FocalLoss()
    segLoss = nn.MSELoss()

    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check
    train_path = data_dict['train']
    test_path = data_dict['val']

    # Freeze
    freeze = []  # parameter names to freeze (full or partial)
    for k, v in model.named_parameters():
        v.requires_grad = True  # train all layers
        if any(x in k for x in freeze):
            print('freezing %s' % k)
            v.requires_grad = False

    # Optimizer
    nbs = 64  # nominal batch size
    accumulate = max(round(nbs / total_batch_size),
                     1)  # accumulate loss before optimizing
    hyp['weight_decay'] *= total_batch_size * accumulate / nbs  # scale weight_decay
    logger.info(f"Scaled weight_decay = {hyp['weight_decay']}")
    print(f"Scaled weight_decay = {hyp['weight_decay']}")

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_modules():
        if hasattr(v, 'bias') and isinstance(v.bias, nn.Parameter):
            pg2.append(v.bias)  # biases
        if isinstance(v, nn.BatchNorm2d):
            pg0.append(v.weight)  # no decay
        elif hasattr(v, 'weight') and isinstance(v.weight, nn.Parameter):
            pg1.append(v.weight)  # apply decay

    if opt.adam:
        optimizer = optim.Adam(pg0,
                               lr=hyp['lr0'],
                               betas=(hyp['momentum'],
                                      0.999))  # adjust beta1 to momentum
    else:
        optimizer = optim.SGD(pg0,
                              lr=hyp['lr0'],
                              momentum=hyp['momentum'],
                              nesterov=True)

    # optimizer = MADGRAD(pg0,  lr=hyp['lr0'], momentum=hyp['momentum'])

    optimizer.add_param_group({
        'params': pg1,
        'weight_decay': hyp['weight_decay']
    })  # add pg1 with weight_decay
    optimizer.add_param_group({'params': pg2})  # add pg2 (biases)
    logger.info('Optimizer groups: %g .bias, %g conv.weight, %g other' %
                (len(pg2), len(pg1), len(pg0)))
    print('Optimizer groups: %g .bias, %g conv.weight, %g other' %
          (len(pg2), len(pg1), len(pg0)))
    del pg0, pg1, pg2

    # Scheduler https://arxiv.org/pdf/1812.01187.pdf
    # https://pytorch.org/docs/stable/_modules/torch/optim/lr_scheduler.html#OneCycleLR
    if opt.linear_lr:
        lf = lambda x: (1 - x / (epochs - 1)) * (1.0 - hyp['lrf']) + hyp[
            'lrf']  # linear
    else:
        lf = one_cycle(1, hyp['lrf'], epochs)  # cosine 1->hyp['lrf']
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # EMA
    ema = ModelEMA(model) if rank in [-1, 0] else None

    # Resume
    start_epoch, best_fitness = 0, 0.0
    # if pretrained:
    if 0:
        # Optimizer
        if ckpt['optimizer'] is not None:
            optimizer.load_state_dict(ckpt['optimizer'])
            best_fitness = ckpt['best_fitness']

        # EMA
        if ema and ckpt.get('ema'):
            ema.ema.load_state_dict(ckpt['ema'].float().state_dict())
            ema.updates = ckpt['updates']

        # Results
        if ckpt.get('training_results') is not None:
            results_file.write_text(
                ckpt['training_results'])  # write results.txt

        # Epochs
        start_epoch = ckpt['epoch'] + 1
        if opt.resume:
            assert start_epoch > 0, '%s training to %g epochs is finished, nothing to resume.' % (
                weights, epochs)
        if epochs < start_epoch:
            logger.info(
                '%s has been trained for %g epochs. Fine-tuning for %g additional epochs.'
                % (weights, ckpt['epoch'], epochs))
            print(
                '%s has been trained for %g epochs. Fine-tuning for %g additional epochs.'
                % (weights, ckpt['epoch'], epochs))
            epochs += ckpt['epoch']  # finetune additional epochs

        del ckpt, state_dict

    # Image sizes
    if hasattr(model, 'model'):
        gs = max(int(model.model.stride.max()), 32)  # grid size (max stride)
        try:
            nl = model.model.model[-1].nl
        except:
            nl = model.model.detection.nl  # number of detection layers (used for scaling hyp['obj'])
    else:
        gs = max(int(model.stride.max()), 32)  # grid size (max stride)
        nl = model.detection.nl  # number of detection layers (used for scaling hyp['obj'])

    imgsz, imgsz_test = [check_img_size(x, gs) for x in opt.img_size
                         ]  # verify imgsz are gs-multiples

    # DP mode
    if cuda and rank == -1 and torch.cuda.device_count() > 1:
        model = torch.nn.DataParallel(model)

    # SyncBatchNorm
    if opt.sync_bn and cuda and rank != -1:
        model = torch.nn.SyncBatchNorm.convert_sync_batchnorm(model).to(device)
        logger.info('Using SyncBatchNorm()')
        print('Using SyncBatchNorm()')

    # Trainloader
    dataloader, dataset = create_dataloader(train_path,
                                            imgsz,
                                            batch_size,
                                            gs,
                                            opt,
                                            hyp=hyp,
                                            augment=True,
                                            cache=opt.cache_images,
                                            rect=opt.rect,
                                            rank=rank,
                                            world_size=opt.world_size,
                                            workers=opt.workers,
                                            image_weights=opt.image_weights,
                                            quad=opt.quad,
                                            prefix=colorstr('train: '))
    mlc = np.concatenate(dataset.labels, 0)[:, 0].max()  # max label class
    nb = len(dataloader)  # number of batches
    assert mlc < nc, 'Label class %g exceeds nc=%g in %s. Possible class labels are 0-%g' % (
        mlc, nc, opt.data, nc - 1)

    # Process 0
    if rank in [-1, 0]:
        # testloader = create_dataloader(test_path, imgsz_test, batch_size*2, gs, opt,  # testloader
        #                                hyp=hyp, cache=opt.cache_images and not opt.notest, rect=True, rank=-1,
        #                                world_size=opt.world_size, workers=opt.workers,
        #                                pad=0.5, prefix=colorstr('val: '))[0]

        testloader = create_dataloader(
            test_path,
            imgsz_test,
            batch_size * 2,
            gs,
            opt,  # testloader
            hyp=hyp,
            cache=opt.cache_images and not opt.notest,
            rect=True,
            rank=-1,
            world_size=opt.world_size,
            workers=opt.workers,
            pad=0.5,
            prefix=colorstr('val: '))[0]

        if not opt.resume:
            labels = np.concatenate(dataset.labels, 0)
            c = torch.tensor(labels[:, 0])  # classes
            # cf = torch.bincount(c.long(), minlength=nc) + 1.  # frequency
            # model._initialize_biases(cf.to(device))
            if plots:
                plot_labels(labels, names, save_dir, loggers)
                if tb_writer:
                    tb_writer.add_histogram('classes', c, 0)

            # Anchors
            if not opt.noautoanchor:
                check_anchors(dataset,
                              model=model,
                              thr=hyp['anchor_t'],
                              imgsz=imgsz)
            model.half().float()  # pre-reduce anchor precision

    # DDP mode
    if cuda and rank != -1:
        model = DDP(model,
                    device_ids=[opt.local_rank],
                    output_device=opt.local_rank)

    # Model parameters
    hyp['box'] *= 3. / nl  # scale to layers
    hyp['cls'] *= nc / 80. * 3. / nl  # scale to classes and layers
    hyp['obj'] *= (imgsz / 640)**2 * 3. / nl  # scale to image size and layers
    hyp['label_smoothing'] = opt.label_smoothing
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # iou loss ratio (obj_loss = 1.0 or iou)
    model.class_weights = labels_to_class_weights(
        dataset.labels, nc).to(device) * nc  # attach class weights
    model.names = names

    # Start training
    t0 = time.time()
    nw = max(round(hyp['warmup_epochs'] * nb),
             1000)  # number of warmup iterations, max(3 epochs, 1k iterations)
    # nw = min(nw, (epochs - start_epoch) / 2 * nb)  # limit warmup to < 1/2 of training
    maps = np.zeros(nc)  # mAP per class
    results = (0, 0, 0, 0, 0, 0, 0
               )  # P, R, [email protected], [email protected], val_loss(box, obj, cls)
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    compute_loss = ComputeLoss(model)  # init loss class
    logger.info(f'Image sizes {imgsz} train, {imgsz_test} test\n'
                f'Using {dataloader.num_workers} dataloader workers\n'
                f'Logging results to {save_dir}\n'
                f'Starting training for {epochs} epochs...')
    print(f'Image sizes {imgsz} train, {imgsz_test} test\n'
          f'Using {dataloader.num_workers} dataloader workers\n'
          f'Logging results to {save_dir}\n'
          f'Starting training for {epochs} epochs...')

    criterion = torch.nn.BCEWithLogitsLoss()

    for epoch in range(
            start_epoch, epochs
    ):  # epoch ------------------------------------------------------------------
        model.train()

        # Update image weights (optional)
        if opt.image_weights:
            # Generate indices
            if rank in [-1, 0]:
                cw = model.class_weights.cpu().numpy() * (
                    1 - maps)**2 / nc  # class weights
                iw = labels_to_image_weights(dataset.labels,
                                             nc=nc,
                                             class_weights=cw)  # image weights
                dataset.indices = random.choices(
                    range(dataset.n), weights=iw,
                    k=dataset.n)  # rand weighted idx
            # Broadcast if DDP
            if rank != -1:
                indices = (torch.tensor(dataset.indices)
                           if rank == 0 else torch.zeros(dataset.n)).int()
                dist.broadcast(indices, 0)
                if rank != 0:
                    dataset.indices = indices.cpu().numpy()

        # Update mosaic border
        # b = int(random.uniform(0.25 * imgsz, 0.75 * imgsz + gs) // gs * gs)
        # dataset.mosaic_border = [b - imgsz, -b]  # height, width borders

        mloss = torch.zeros(4, device=device)  # mean losses
        if rank != -1:
            dataloader.sampler.set_epoch(epoch)
        pbar = enumerate(dataloader)
        logger.info(('\n' + '%10s' * 11) %
                    ('Epoch', 'gpu_mem', 'box', 'obj', 'cls', 'total',
                     'labels', 'img_size', 'hm loss', 'lo_loss', 'loss'))
        print(('\n' + '%10s' * 11) %
              ('Epoch', 'gpu_mem', 'box', 'obj', 'cls', 'total', 'labels',
               'img_size', 'hm loss', 'lo_loss', 'loss'))
        if rank in [-1, 0]:
            pbar = tqdm(pbar, total=nb)  # progress bar
        optimizer.zero_grad()
        for i, (
                imgs, hms, targets, paths, _, logt
        ) in pbar:  # batch -------------------------------------------------------------
            ni = i + nb * epoch  # number integrated batches (since train start)
            imgs = imgs.to(device, non_blocking=True).float(
            ) / 255.0  # uint8 to float32, 0-255 to 0.0-1.0

            hms = hms.to(device, non_blocking=True).float()

            # print(hms.shape, imgs.shape)
            # if i>10:
            #     break
            # print('output_layer====output_layer: ',torch.max(hms))

            # Warmup
            if ni <= nw:
                xi = [0, nw]  # x interp
                # model.gr = np.interp(ni, xi, [0.0, 1.0])  # iou loss ratio (obj_loss = 1.0 or iou)
                accumulate = max(
                    1,
                    np.interp(ni, xi, [1, nbs / total_batch_size]).round())
                for j, x in enumerate(optimizer.param_groups):
                    # bias lr falls from 0.1 to lr0, all other lrs rise from 0.0 to lr0
                    x['lr'] = np.interp(ni, xi, [
                        hyp['warmup_bias_lr'] if j == 2 else 0.0,
                        x['initial_lr'] * lf(epoch)
                    ])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(
                            ni, xi, [hyp['warmup_momentum'], hyp['momentum']])

            # Multi-scale
            if opt.multi_scale:
                sz = random.randrange(imgsz * 0.5,
                                      imgsz * 1.5 + gs) // gs * gs  # size
                sf = sz / max(imgs.shape[2:])  # scale factor
                if sf != 1:
                    ns = [math.ceil(x * sf / gs) * gs for x in imgs.shape[2:]
                          ]  # new shape (stretched to gs-multiple)
                    imgs = F.interpolate(imgs,
                                         size=ns,
                                         mode='bilinear',
                                         align_corners=False)

            # Forward
            with amp.autocast(enabled=cuda):
                pred, seg_out, logits = model(imgs)  # forward
                loss, loss_items = compute_loss(
                    pred, targets.to(device))  # loss scaled by batch_size
                if rank != -1:
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode
                if opt.quad:
                    loss *= 4.

                # print(seg_out.shape)

                seg_out = _sigmoid(seg_out)

                # seg_out = seg_out[:,0,:,:]
                hms = torch.unsqueeze(hms, 1)

                # print(hms.shape, seg_out.shape)

                # print(targets.shape, imgs.shape, logits.shape, paths.shape)
                # logits = torch.clip(logits, -11, 11)
                # print(logits)
                logit_loss = criterion(logits, logt.to(device))

                hm_loss = segLoss(seg_out, hms)
                # print(hm_loss)

                ratio = sigmoid_rampup(epoch, int(40 * epochs / 50))
                ratio = 10 * (1 - ratio)

                loss = 1 * loss + ratio * hm_loss + 0.5 * logit_loss

            # Backward
            scaler.scale(loss).backward()

            # Optimize
            if ni % accumulate == 0:
                scaler.step(optimizer)  # optimizer.step
                scaler.update()
                optimizer.zero_grad()
                if ema:
                    ema.update(model)

            # Print
            if rank in [-1, 0]:
                mloss = (mloss * i + loss_items) / (i + 1
                                                    )  # update mean losses
                mem = '%.3gG' % (torch.cuda.memory_reserved() / 1E9
                                 if torch.cuda.is_available() else 0)  # (GB)
                s = ('%10s' * 2 + '%10.4g' * 9) % (
                    '%g/%g' %
                    (epoch, epochs - 1), mem, *mloss, targets.shape[0],
                    imgs.shape[-1], hm_loss, logit_loss, loss)
                pbar.set_description(s)

                # Plot
                if plots and ni < 3:
                    f = save_dir / f'train_batch{ni}.jpg'  # filename
                    Thread(target=plot_images,
                           args=(imgs, hms, targets, paths, f),
                           daemon=True).start()
                    # if tb_writer:
                    #     tb_writer.add_image(f, result, dataformats='HWC', global_step=epoch)
                    #     tb_writer.add_graph(model, imgs)  # add model to tensorboard
                elif plots and ni == 10 and wandb_logger.wandb:
                    wandb_logger.log({
                        "Mosaics": [
                            wandb_logger.wandb.Image(str(x), caption=x.name)
                            for x in save_dir.glob('train*.jpg') if x.exists()
                        ]
                    })

            # end batch ------------------------------------------------------------------------------------------------
        # end epoch ----------------------------------------------------------------------------------------------------

        # Scheduler
        lr = [x['lr'] for x in optimizer.param_groups]  # for tensorboard
        scheduler.step()

        # DDP process 0 or single-GPU
        if rank in [-1, 0]:
            # mAP
            ema.update_attr(model,
                            include=[
                                'yaml', 'nc', 'hyp', 'gr', 'names', 'stride',
                                'class_weights'
                            ])
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                wandb_logger.current_epoch = epoch + 1
                results, maps, times = test.test(data_dict,
                                                 batch_size=batch_size * 2,
                                                 imgsz=imgsz_test,
                                                 model=ema.ema,
                                                 single_cls=opt.single_cls,
                                                 dataloader=testloader,
                                                 save_dir=save_dir,
                                                 verbose=nc < 50
                                                 and final_epoch,
                                                 plots=plots and final_epoch,
                                                 wandb_logger=wandb_logger,
                                                 compute_loss=compute_loss,
                                                 is_coco=is_coco)

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # append metrics, val_loss
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Log
            tags = [
                'train/box_loss',
                'train/obj_loss',
                'train/cls_loss',  # train loss
                'metrics/precision',
                'metrics/recall',
                'metrics/mAP_0.5',
                'metrics/mAP_0.5:0.95',
                'val/box_loss',
                'val/obj_loss',
                'val/cls_loss',  # val loss
                'x/lr0',
                'x/lr1',
                'x/lr2'
            ]  # params
            for x, tag in zip(list(mloss[:-1]) + list(results) + lr, tags):
                if tb_writer:
                    tb_writer.add_scalar(tag, x, epoch)  # tensorboard
                if wandb_logger.wandb:
                    wandb_logger.log({tag: x})  # W&B

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # weighted combination of [P, R, [email protected], [email protected]]
            if fi > best_fitness:
                best_fitness = fi
            wandb_logger.end_epoch(best_result=best_fitness == fi)

            # Save model
            if (not opt.nosave) or (final_epoch and not opt.evolve):  # if save
                ckpt = {
                    'epoch':
                    epoch,
                    'best_fitness':
                    best_fitness,
                    'training_results':
                    results_file.read_text(),
                    'model':
                    deepcopy(
                        model.module if is_parallel(model) else model).half(),
                    'ema':
                    deepcopy(ema.ema).half(),
                    'updates':
                    ema.updates,
                    'optimizer':
                    optimizer.state_dict(),
                    'wandb_id':
                    wandb_logger.wandb_run.id if wandb_logger.wandb else None
                }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                if wandb_logger.wandb:
                    if ((epoch + 1) % opt.save_period == 0
                            and not final_epoch) and opt.save_period != -1:
                        wandb_logger.log_model(last.parent,
                                               opt,
                                               epoch,
                                               fi,
                                               best_model=best_fitness == fi)
                del ckpt

        # end epoch ----------------------------------------------------------------------------------------------------
    # end training
    if rank in [-1, 0]:
        # Plots
        if plots:
            plot_results(save_dir=save_dir)  # save as results.png
            if wandb_logger.wandb:
                files = [
                    'results.png', 'confusion_matrix.png',
                    *[f'{x}_curve.png' for x in ('F1', 'PR', 'P', 'R')]
                ]
                wandb_logger.log({
                    "Results": [
                        wandb_logger.wandb.Image(str(save_dir / f), caption=f)
                        for f in files if (save_dir / f).exists()
                    ]
                })
        # Test best.pt
        logger.info('%g epochs completed in %.3f hours.\n' %
                    (epoch - start_epoch + 1, (time.time() - t0) / 3600))
        print('%g epochs completed in %.3f hours.\n' %
              (epoch - start_epoch + 1, (time.time() - t0) / 3600))
        if opt.data.endswith('coco.yaml') and nc == 80:  # if COCO
            for m in (last,
                      best) if best.exists() else (last):  # speed, mAP tests
                results, _, _ = test.test(opt.data,
                                          batch_size=batch_size * 2,
                                          imgsz=imgsz_test,
                                          conf_thres=0.001,
                                          iou_thres=0.7,
                                          model=attempt_load(m, device).half(),
                                          single_cls=opt.single_cls,
                                          dataloader=testloader,
                                          save_dir=save_dir,
                                          save_json=True,
                                          plots=False,
                                          is_coco=is_coco)

        # Strip optimizers
        final = best if best.exists() else last  # final model
        for f in last, best:
            if f.exists():
                strip_optimizer(f)  # strip optimizers
        if opt.bucket:
            os.system(f'gsutil cp {final} gs://{opt.bucket}/weights')  # upload
        if wandb_logger.wandb and not opt.evolve:  # Log the stripped model
            wandb_logger.wandb.log_artifact(
                str(final),
                type='model',
                name='run_' + wandb_logger.wandb_run.id + '_model',
                aliases=['last', 'best', 'stripped'])
        wandb_logger.finish_run()
    else:
        dist.destroy_process_group()
    torch.cuda.empty_cache()
    return results
Пример #2
0
def train(
    hyp,  # path/to/hyp.yaml or hyp dictionary
    opt,
    device,
):
    save_dir, epochs, batch_size, weights, single_cls, evolve, data, cfg, resume, noval, nosave, workers, = \
        opt.save_dir, opt.epochs, opt.batch_size, opt.weights, opt.single_cls, opt.evolve, opt.data, opt.cfg, \
        opt.resume, opt.noval, opt.nosave, opt.workers

    # Directories
    save_dir = Path(save_dir)
    wdir = save_dir / 'weights'
    wdir.mkdir(parents=True, exist_ok=True)  # make dir
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    results_file = save_dir / 'results.txt'

    # Hyperparameters
    if isinstance(hyp, str):
        with open(hyp) as f:
            hyp = yaml.safe_load(f)  # load hyps dict
    LOGGER.info(
        colorstr('hyperparameters: ') + ', '.join(f'{k}={v}'
                                                  for k, v in hyp.items()))

    # Save run settings
    with open(save_dir / 'hyp.yaml', 'w') as f:
        yaml.safe_dump(hyp, f, sort_keys=False)
    with open(save_dir / 'opt.yaml', 'w') as f:
        yaml.safe_dump(vars(opt), f, sort_keys=False)

    # Configure
    plots = not evolve  # create plots
    cuda = device.type != 'cpu'
    init_seeds(1 + RANK)
    with open(data) as f:
        data_dict = yaml.safe_load(f)  # data dict

    # Loggers
    loggers = {'wandb': None, 'tb': None}  # loggers dict
    if RANK in [-1, 0]:
        # TensorBoard
        if not evolve:
            prefix = colorstr('tensorboard: ')
            LOGGER.info(
                f"{prefix}Start with 'tensorboard --logdir {opt.project}', view at http://localhost:6006/"
            )
            loggers['tb'] = SummaryWriter(str(save_dir))

        # W&B
        opt.hyp = hyp  # add hyperparameters
        run_id = torch.load(weights).get('wandb_id') if weights.endswith(
            '.pt') and os.path.isfile(weights) else None
        run_id = run_id if opt.resume else None  # start fresh run if transfer learning
        wandb_logger = WandbLogger(opt, save_dir.stem, run_id, data_dict)
        loggers['wandb'] = wandb_logger.wandb
        if loggers['wandb']:
            data_dict = wandb_logger.data_dict
            weights, epochs, hyp = opt.weights, opt.epochs, opt.hyp  # may update weights, epochs if resuming

    nc = 1 if single_cls else int(data_dict['nc'])  # number of classes
    names = ['item'] if single_cls and len(
        data_dict['names']) != 1 else data_dict['names']  # class names
    assert len(names) == nc, '%g names found for nc=%g dataset in %s' % (
        len(names), nc, data)  # check
    is_coco = data.endswith('coco.yaml') and nc == 80  # COCO dataset

    # Model
    pretrained = weights.endswith('.pt')
    if pretrained:
        with torch_distributed_zero_first(RANK):
            weights = attempt_download(
                weights)  # download if not found locally
        ckpt = torch.load(weights, map_location=device)  # load checkpoint
        model = Model(cfg or ckpt['model'].yaml,
                      ch=3,
                      nc=nc,
                      anchors=hyp.get('anchors')).to(device)  # create
        exclude = [
            'anchor'
        ] if (cfg or hyp.get('anchors')) and not resume else []  # exclude keys
        state_dict = ckpt['model'].float().state_dict()  # to FP32
        state_dict = intersect_dicts(state_dict,
                                     model.state_dict(),
                                     exclude=exclude)  # intersect
        model.load_state_dict(state_dict, strict=False)  # load
        LOGGER.info(
            'Transferred %g/%g items from %s' %
            (len(state_dict), len(model.state_dict()), weights))  # report
    else:
        model = Model(cfg, ch=3, nc=nc,
                      anchors=hyp.get('anchors')).to(device)  # create
    with torch_distributed_zero_first(RANK):
        check_dataset(data_dict)  # check
    train_path = data_dict['train']
    val_path = data_dict['val']

    # Freeze
    freeze = []  # parameter names to freeze (full or partial)
    for k, v in model.named_parameters():
        v.requires_grad = True  # train all layers
        if any(x in k for x in freeze):
            print('freezing %s' % k)
            v.requires_grad = False

    # Optimizer
    nbs = 64  # nominal batch size
    accumulate = max(round(nbs / batch_size),
                     1)  # accumulate loss before optimizing
    hyp['weight_decay'] *= batch_size * accumulate / nbs  # scale weight_decay
    LOGGER.info(f"Scaled weight_decay = {hyp['weight_decay']}")

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_modules():
        if hasattr(v, 'bias') and isinstance(v.bias, nn.Parameter):
            pg2.append(v.bias)  # biases
        if isinstance(v, nn.BatchNorm2d):
            pg0.append(v.weight)  # no decay
        elif hasattr(v, 'weight') and isinstance(v.weight, nn.Parameter):
            pg1.append(v.weight)  # apply decay

    if opt.adam:
        optimizer = optim.Adam(pg0,
                               lr=hyp['lr0'],
                               betas=(hyp['momentum'],
                                      0.999))  # adjust beta1 to momentum
    else:
        optimizer = optim.SGD(pg0,
                              lr=hyp['lr0'],
                              momentum=hyp['momentum'],
                              nesterov=True)

    optimizer.add_param_group({
        'params': pg1,
        'weight_decay': hyp['weight_decay']
    })  # add pg1 with weight_decay
    optimizer.add_param_group({'params': pg2})  # add pg2 (biases)
    LOGGER.info('Optimizer groups: %g .bias, %g conv.weight, %g other' %
                (len(pg2), len(pg1), len(pg0)))
    del pg0, pg1, pg2

    # Scheduler https://arxiv.org/pdf/1812.01187.pdf
    # https://pytorch.org/docs/stable/_modules/torch/optim/lr_scheduler.html#OneCycleLR
    if opt.linear_lr:
        lf = lambda x: (1 - x / (epochs - 1)) * (1.0 - hyp['lrf']) + hyp[
            'lrf']  # linear
    else:
        lf = one_cycle(1, hyp['lrf'], epochs)  # cosine 1->hyp['lrf']
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # EMA
    ema = ModelEMA(model) if RANK in [-1, 0] else None

    # Resume
    start_epoch, best_fitness = 0, 0.0
    if pretrained:
        # Optimizer
        if ckpt['optimizer'] is not None:
            optimizer.load_state_dict(ckpt['optimizer'])
            best_fitness = ckpt['best_fitness']

        # EMA
        if ema and ckpt.get('ema'):
            ema.ema.load_state_dict(ckpt['ema'].float().state_dict())
            ema.updates = ckpt['updates']

        # Results
        if ckpt.get('training_results') is not None:
            results_file.write_text(
                ckpt['training_results'])  # write results.txt

        # Epochs
        start_epoch = ckpt['epoch'] + 1
        if resume:
            assert start_epoch > 0, '%s training to %g epochs is finished, nothing to resume.' % (
                weights, epochs)
        if epochs < start_epoch:
            LOGGER.info(
                '%s has been trained for %g epochs. Fine-tuning for %g additional epochs.'
                % (weights, ckpt['epoch'], epochs))
            epochs += ckpt['epoch']  # finetune additional epochs

        del ckpt, state_dict

    # Image sizes
    gs = max(int(model.stride.max()), 32)  # grid size (max stride)
    nl = model.model[
        -1].nl  # number of detection layers (used for scaling hyp['obj'])
    imgsz = check_img_size(opt.imgsz, gs,
                           floor=gs * 2)  # verify imgsz is gs-multiple

    # DP mode
    if cuda and RANK == -1 and torch.cuda.device_count() > 1:
        logging.warning(
            'DP not recommended, instead use torch.distributed.run for best DDP Multi-GPU results.\n'
            'See Multi-GPU Tutorial at https://github.com/ultralytics/yolov5/issues/475 to get started.'
        )
        model = torch.nn.DataParallel(model)

    # SyncBatchNorm
    if opt.sync_bn and cuda and RANK != -1:
        raise Exception(
            'can not train with --sync-bn, known issue https://github.com/ultralytics/yolov5/issues/3998'
        )
        model = torch.nn.SyncBatchNorm.convert_sync_batchnorm(model).to(device)
        LOGGER.info('Using SyncBatchNorm()')

    # Trainloader
    train_loader, dataset = create_dataloader(train_path,
                                              imgsz,
                                              batch_size // WORLD_SIZE,
                                              gs,
                                              single_cls,
                                              hyp=hyp,
                                              augment=True,
                                              cache=opt.cache_images,
                                              rect=opt.rect,
                                              rank=RANK,
                                              workers=workers,
                                              image_weights=opt.image_weights,
                                              quad=opt.quad,
                                              prefix=colorstr('train: '))
    mlc = np.concatenate(dataset.labels, 0)[:, 0].max()  # max label class
    nb = len(train_loader)  # number of batches
    assert mlc < nc, 'Label class %g exceeds nc=%g in %s. Possible class labels are 0-%g' % (
        mlc, nc, data, nc - 1)

    # Process 0
    if RANK in [-1, 0]:
        val_loader = create_dataloader(val_path,
                                       imgsz,
                                       batch_size // WORLD_SIZE * 2,
                                       gs,
                                       single_cls,
                                       hyp=hyp,
                                       cache=opt.cache_images and not noval,
                                       rect=True,
                                       rank=-1,
                                       workers=workers,
                                       pad=0.5,
                                       prefix=colorstr('val: '))[0]

        if not resume:
            labels = np.concatenate(dataset.labels, 0)
            # c = torch.tensor(labels[:, 0])  # classes
            # cf = torch.bincount(c.long(), minlength=nc) + 1.  # frequency
            # model._initialize_biases(cf.to(device))
            if plots:
                plot_labels(labels, names, save_dir, loggers)

            # Anchors
            if not opt.noautoanchor:
                check_anchors(dataset,
                              model=model,
                              thr=hyp['anchor_t'],
                              imgsz=imgsz)
            model.half().float()  # pre-reduce anchor precision

    # DDP mode
    if cuda and RANK != -1:
        model = DDP(model, device_ids=[LOCAL_RANK], output_device=LOCAL_RANK)

    # Model parameters
    hyp['box'] *= 3. / nl  # scale to layers
    hyp['cls'] *= nc / 80. * 3. / nl  # scale to classes and layers
    hyp['obj'] *= (imgsz / 640)**2 * 3. / nl  # scale to image size and layers
    hyp['label_smoothing'] = opt.label_smoothing
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # iou loss ratio (obj_loss = 1.0 or iou)
    model.class_weights = labels_to_class_weights(
        dataset.labels, nc).to(device) * nc  # attach class weights
    model.names = names

    # Start training
    t0 = time.time()
    nw = max(round(hyp['warmup_epochs'] * nb),
             1000)  # number of warmup iterations, max(3 epochs, 1k iterations)
    # nw = min(nw, (epochs - start_epoch) / 2 * nb)  # limit warmup to < 1/2 of training
    last_opt_step = -1
    maps = np.zeros(nc)  # mAP per class
    results = (0, 0, 0, 0, 0, 0, 0
               )  # P, R, [email protected], [email protected], val_loss(box, obj, cls)
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    compute_loss = ComputeLoss(model)  # init loss class
    LOGGER.info(f'Image sizes {imgsz} train, {imgsz} val\n'
                f'Using {train_loader.num_workers} dataloader workers\n'
                f'Logging results to {save_dir}\n'
                f'Starting training for {epochs} epochs...')
    for epoch in range(
            start_epoch, epochs
    ):  # epoch ------------------------------------------------------------------
        model.train()

        # Update image weights (optional)
        if opt.image_weights:
            # Generate indices
            if RANK in [-1, 0]:
                cw = model.class_weights.cpu().numpy() * (
                    1 - maps)**2 / nc  # class weights
                iw = labels_to_image_weights(dataset.labels,
                                             nc=nc,
                                             class_weights=cw)  # image weights
                dataset.indices = random.choices(
                    range(dataset.n), weights=iw,
                    k=dataset.n)  # rand weighted idx
            # Broadcast if DDP
            if RANK != -1:
                indices = (torch.tensor(dataset.indices)
                           if RANK == 0 else torch.zeros(dataset.n)).int()
                dist.broadcast(indices, 0)
                if RANK != 0:
                    dataset.indices = indices.cpu().numpy()

        # Update mosaic border
        # b = int(random.uniform(0.25 * imgsz, 0.75 * imgsz + gs) // gs * gs)
        # dataset.mosaic_border = [b - imgsz, -b]  # height, width borders

        mloss = torch.zeros(4, device=device)  # mean losses
        if RANK != -1:
            train_loader.sampler.set_epoch(epoch)
        pbar = enumerate(train_loader)
        LOGGER.info(
            ('\n' + '%10s' * 8) % ('Epoch', 'gpu_mem', 'box', 'obj', 'cls',
                                   'total', 'labels', 'img_size'))
        if RANK in [-1, 0]:
            pbar = tqdm(pbar, total=nb)  # progress bar
        optimizer.zero_grad()
        for i, (
                imgs, targets, paths, _
        ) in pbar:  # batch -------------------------------------------------------------
            ni = i + nb * epoch  # number integrated batches (since train start)
            imgs = imgs.to(device, non_blocking=True).float(
            ) / 255.0  # uint8 to float32, 0-255 to 0.0-1.0

            # Warmup
            if ni <= nw:
                xi = [0, nw]  # x interp
                # model.gr = np.interp(ni, xi, [0.0, 1.0])  # iou loss ratio (obj_loss = 1.0 or iou)
                accumulate = max(
                    1,
                    np.interp(ni, xi, [1, nbs / batch_size]).round())
                for j, x in enumerate(optimizer.param_groups):
                    # bias lr falls from 0.1 to lr0, all other lrs rise from 0.0 to lr0
                    x['lr'] = np.interp(ni, xi, [
                        hyp['warmup_bias_lr'] if j == 2 else 0.0,
                        x['initial_lr'] * lf(epoch)
                    ])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(
                            ni, xi, [hyp['warmup_momentum'], hyp['momentum']])

            # Multi-scale
            if opt.multi_scale:
                sz = random.randrange(imgsz * 0.5,
                                      imgsz * 1.5 + gs) // gs * gs  # size
                sf = sz / max(imgs.shape[2:])  # scale factor
                if sf != 1:
                    ns = [math.ceil(x * sf / gs) * gs for x in imgs.shape[2:]
                          ]  # new shape (stretched to gs-multiple)
                    imgs = F.interpolate(imgs,
                                         size=ns,
                                         mode='bilinear',
                                         align_corners=False)

            # Forward
            with amp.autocast(enabled=cuda):
                pred = model(imgs)  # forward
                loss, loss_items = compute_loss(
                    pred, targets.to(device))  # loss scaled by batch_size
                if RANK != -1:
                    loss *= WORLD_SIZE  # gradient averaged between devices in DDP mode
                if opt.quad:
                    loss *= 4.

            # Backward
            scaler.scale(loss).backward()

            # Optimize
            if ni - last_opt_step >= accumulate:
                scaler.step(optimizer)  # optimizer.step
                scaler.update()
                optimizer.zero_grad()
                if ema:
                    ema.update(model)
                last_opt_step = ni

            # Print
            if RANK in [-1, 0]:
                mloss = (mloss * i + loss_items) / (i + 1
                                                    )  # update mean losses
                mem = '%.3gG' % (torch.cuda.memory_reserved() / 1E9
                                 if torch.cuda.is_available() else 0)  # (GB)
                s = ('%10s' * 2 +
                     '%10.4g' * 6) % (f'{epoch}/{epochs - 1}', mem, *mloss,
                                      targets.shape[0], imgs.shape[-1])
                pbar.set_description(s)

                # Plot
                if plots and ni < 3:
                    f = save_dir / f'train_batch{ni}.jpg'  # filename
                    Thread(target=plot_images,
                           args=(imgs, targets, paths, f),
                           daemon=True).start()
                    if loggers['tb'] and ni == 0:  # TensorBoard
                        with warnings.catch_warnings():
                            warnings.simplefilter(
                                'ignore')  # suppress jit trace warning
                            loggers['tb'].add_graph(
                                torch.jit.trace(de_parallel(model),
                                                imgs[0:1],
                                                strict=False), [])
                elif plots and ni == 10 and loggers['wandb']:
                    wandb_logger.log({
                        'Mosaics': [
                            loggers['wandb'].Image(str(x), caption=x.name)
                            for x in save_dir.glob('train*.jpg') if x.exists()
                        ]
                    })

            # end batch ------------------------------------------------------------------------------------------------

        # Scheduler
        lr = [x['lr'] for x in optimizer.param_groups]  # for loggers
        scheduler.step()

        # DDP process 0 or single-GPU
        if RANK in [-1, 0]:
            # mAP
            ema.update_attr(model,
                            include=[
                                'yaml', 'nc', 'hyp', 'gr', 'names', 'stride',
                                'class_weights'
                            ])
            final_epoch = epoch + 1 == epochs
            if not noval or final_epoch:  # Calculate mAP
                wandb_logger.current_epoch = epoch + 1
                results, maps, _ = val.run(data_dict,
                                           batch_size=batch_size //
                                           WORLD_SIZE * 2,
                                           imgsz=imgsz,
                                           model=ema.ema,
                                           single_cls=single_cls,
                                           dataloader=val_loader,
                                           save_dir=save_dir,
                                           save_json=is_coco and final_epoch,
                                           verbose=nc < 50 and final_epoch,
                                           plots=plots and final_epoch,
                                           wandb_logger=wandb_logger,
                                           compute_loss=compute_loss)

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # append metrics, val_loss

            # Log
            tags = [
                'train/box_loss',
                'train/obj_loss',
                'train/cls_loss',  # train loss
                'metrics/precision',
                'metrics/recall',
                'metrics/mAP_0.5',
                'metrics/mAP_0.5:0.95',
                'val/box_loss',
                'val/obj_loss',
                'val/cls_loss',  # val loss
                'x/lr0',
                'x/lr1',
                'x/lr2'
            ]  # params
            for x, tag in zip(list(mloss[:-1]) + list(results) + lr, tags):
                if loggers['tb']:
                    loggers['tb'].add_scalar(tag, x, epoch)  # TensorBoard
                if loggers['wandb']:
                    wandb_logger.log({tag: x})  # W&B

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # weighted combination of [P, R, [email protected], [email protected]]
            if fi > best_fitness:
                best_fitness = fi
            wandb_logger.end_epoch(best_result=best_fitness == fi)

            # Save model
            if (not nosave) or (final_epoch and not evolve):  # if save
                ckpt = {
                    'epoch':
                    epoch,
                    'best_fitness':
                    best_fitness,
                    'training_results':
                    results_file.read_text(),
                    'model':
                    deepcopy(de_parallel(model)).half(),
                    'ema':
                    deepcopy(ema.ema).half(),
                    'updates':
                    ema.updates,
                    'optimizer':
                    optimizer.state_dict(),
                    'wandb_id':
                    wandb_logger.wandb_run.id if loggers['wandb'] else None
                }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                if loggers['wandb']:
                    if ((epoch + 1) % opt.save_period == 0
                            and not final_epoch) and opt.save_period != -1:
                        wandb_logger.log_model(last.parent,
                                               opt,
                                               epoch,
                                               fi,
                                               best_model=best_fitness == fi)
                del ckpt

        # end epoch ----------------------------------------------------------------------------------------------------
    # end training -----------------------------------------------------------------------------------------------------
    if RANK in [-1, 0]:
        LOGGER.info(
            f'{epoch - start_epoch + 1} epochs completed in {(time.time() - t0) / 3600:.3f} hours.\n'
        )
        if plots:
            plot_results(save_dir=save_dir)  # save as results.png
            if loggers['wandb']:
                files = [
                    'results.png', 'confusion_matrix.png',
                    *[f'{x}_curve.png' for x in ('F1', 'PR', 'P', 'R')]
                ]
                wandb_logger.log({
                    "Results": [
                        loggers['wandb'].Image(str(save_dir / f), caption=f)
                        for f in files if (save_dir / f).exists()
                    ]
                })

        if not evolve:
            if is_coco:  # COCO dataset
                for m in [last, best
                          ] if best.exists() else [last]:  # speed, mAP tests
                    results, _, _ = val.run(
                        data_dict,
                        batch_size=batch_size // WORLD_SIZE * 2,
                        imgsz=imgsz,
                        model=attempt_load(m, device).half(),
                        single_cls=single_cls,
                        dataloader=val_loader,
                        save_dir=save_dir,
                        save_json=True,
                        plots=False)

            # Strip optimizers
            for f in last, best:
                if f.exists():
                    strip_optimizer(f)  # strip optimizers
            if loggers['wandb']:  # Log the stripped model
                loggers['wandb'].log_artifact(
                    str(best if best.exists() else last),
                    type='model',
                    name='run_' + wandb_logger.wandb_run.id + '_model',
                    aliases=['latest', 'best', 'stripped'])
        wandb_logger.finish_run()

    torch.cuda.empty_cache()
    return results
Пример #3
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(
        colorstr("hyperparameters: ") + ", ".join(f"{k}={v}"
                                                  for k, v in hyp.items()))
    save_dir, epochs, batch_size, total_batch_size, weights, rank = (
        Path(opt.save_dir),  # save_dir
        opt.epochs,
        opt.batch_size,
        opt.total_batch_size,
        opt.weights,
        opt.global_rank,
    )

    # Directories
    wdir = save_dir / "weights"
    wdir.mkdir(parents=True, exist_ok=True)  # make dir
    last = wdir / "last.pt"
    best = wdir / "best.pt"
    results_file = save_dir / "results.txt"

    # Save run settings
    with open(save_dir / "hyp.yaml", "w") as f:
        yaml.safe_dump(hyp, f, sort_keys=False)
    with open(save_dir / "opt.yaml", "w") as f:
        yaml.safe_dump(vars(opt), f, sort_keys=False)

    # Configure
    plots = not opt.evolve  # create plots
    cuda = device.type != "cpu"
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.safe_load(f)  # data dict
    is_coco = opt.data.endswith("coco.yaml")

    # Logging- Doing this before checking the dataset. Might update data_dict
    loggers = {"wandb": None}  # loggers dict
    if rank in [-1, 0]:
        opt.hyp = hyp  # add hyperparameters
        run_id = (torch.load(weights).get("wandb_id")
                  if weights.endswith(".pt") and os.path.isfile(weights) else
                  None)
        wandb_logger = WandbLogger(opt, save_dir.stem, run_id, data_dict)
        loggers["wandb"] = wandb_logger.wandb
        data_dict = wandb_logger.data_dict
        if wandb_logger.wandb:
            weights, epochs, hyp = (
                opt.weights,
                opt.epochs,
                opt.hyp,
            )  # WandbLogger might update weights, epochs if resuming

    nc = 1 if opt.single_cls else int(data_dict["nc"])  # number of classes
    names = (["item"] if opt.single_cls and len(data_dict["names"]) != 1 else
             data_dict["names"])  # class names
    assert len(names) == nc, "%g names found for nc=%g dataset in %s" % (
        len(names),
        nc,
        opt.data,
    )  # check

    # Model
    pretrained = weights.endswith(".pt")
    if pretrained:
        with torch_distributed_zero_first(rank):
            attempt_download(weights)  # download if not found locally
        ckpt = torch.load(weights, map_location=device)  # load checkpoint
        model = Model(opt.cfg or ckpt["model"].yaml,
                      ch=3,
                      nc=nc,
                      anchors=hyp.get("anchors")).to(device)  # create
        exclude = (["anchor"] if
                   (opt.cfg or hyp.get("anchors")) and not opt.resume else []
                   )  # exclude keys
        state_dict = ckpt["model"].float().state_dict()  # to FP32
        state_dict = intersect_dicts(state_dict,
                                     model.state_dict(),
                                     exclude=exclude)  # intersect
        model.load_state_dict(state_dict, strict=False)  # load
        logger.info(
            "Transferred %g/%g items from %s" %
            (len(state_dict), len(model.state_dict()), weights))  # report
    else:
        model = Model(opt.cfg, ch=3, nc=nc,
                      anchors=hyp.get("anchors")).to(device)  # create
    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check

    # -------------- SageMaker の train と val  ------------- #
    #train_path = data_dict["train"]
    #test_path = data_dict["val"]

    data_path = opt.data_dir
    train_path = data_path + "/train2017.txt"
    test_path = data_path + "/val2017.txt"

    # Freeze
    freeze = []  # parameter names to freeze (full or partial)
    for k, v in model.named_parameters():
        v.requires_grad = True  # train all layers
        if any(x in k for x in freeze):
            print("freezing %s" % k)
            v.requires_grad = False

    # Optimizer
    nbs = 64  # nominal batch size
    accumulate = max(round(nbs / total_batch_size),
                     1)  # accumulate loss before optimizing
    hyp["weight_decay"] *= total_batch_size * accumulate / nbs  # scale weight_decay
    logger.info(f"Scaled weight_decay = {hyp['weight_decay']}")

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_modules():
        if hasattr(v, "bias") and isinstance(v.bias, nn.Parameter):
            pg2.append(v.bias)  # biases
        if isinstance(v, nn.BatchNorm2d):
            pg0.append(v.weight)  # no decay
        elif hasattr(v, "weight") and isinstance(v.weight, nn.Parameter):
            pg1.append(v.weight)  # apply decay

    if opt.adam:
        optimizer = optim.Adam(pg0,
                               lr=hyp["lr0"],
                               betas=(hyp["momentum"],
                                      0.999))  # adjust beta1 to momentum
    else:
        optimizer = optim.SGD(pg0,
                              lr=hyp["lr0"],
                              momentum=hyp["momentum"],
                              nesterov=True)

    optimizer.add_param_group({
        "params": pg1,
        "weight_decay": hyp["weight_decay"]
    })  # add pg1 with weight_decay
    optimizer.add_param_group({"params": pg2})  # add pg2 (biases)
    logger.info("Optimizer groups: %g .bias, %g conv.weight, %g other" %
                (len(pg2), len(pg1), len(pg0)))
    del pg0, pg1, pg2

    # Scheduler https://arxiv.org/pdf/1812.01187.pdf
    # https://pytorch.org/docs/stable/_modules/torch/optim/lr_scheduler.html#OneCycleLR
    if opt.linear_lr:
        lf = (lambda x: (1 - x / (epochs - 1)) *
              (1.0 - hyp["lrf"]) + hyp["lrf"])  # linear
    else:
        lf = one_cycle(1, hyp["lrf"], epochs)  # cosine 1->hyp['lrf']
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # EMA
    ema = ModelEMA(model) if rank in [-1, 0] else None

    # Resume
    start_epoch, best_fitness = 0, 0.0
    if pretrained:
        # Optimizer
        if ckpt["optimizer"] is not None:
            optimizer.load_state_dict(ckpt["optimizer"])
            best_fitness = ckpt["best_fitness"]

        # EMA
        if ema and ckpt.get("ema"):
            ema.ema.load_state_dict(ckpt["ema"].float().state_dict())
            ema.updates = ckpt["updates"]

        # Results
        if ckpt.get("training_results") is not None:
            results_file.write_text(
                ckpt["training_results"])  # write results.txt

        # Epochs
        start_epoch = ckpt["epoch"] + 1
        if opt.resume:
            assert (
                start_epoch > 0
            ), "%s training to %g epochs is finished, nothing to resume." % (
                weights,
                epochs,
            )
        if epochs < start_epoch:
            logger.info(
                "%s has been trained for %g epochs. Fine-tuning for %g additional epochs."
                % (weights, ckpt["epoch"], epochs))
            epochs += ckpt["epoch"]  # finetune additional epochs

        del ckpt, state_dict

    # Image sizes
    gs = max(int(model.stride.max()), 32)  # grid size (max stride)
    nl = model.model[
        -1].nl  # number of detection layers (used for scaling hyp['obj'])
    imgsz, imgsz_test = [check_img_size(x, gs) for x in opt.img_size
                         ]  # verify imgsz are gs-multiples

    # DP mode
    if cuda and rank == -1 and torch.cuda.device_count() > 1:
        model = torch.nn.DataParallel(model)

    # SyncBatchNorm
    if opt.sync_bn and cuda and rank != -1:
        model = torch.nn.SyncBatchNorm.convert_sync_batchnorm(model).to(device)
        logger.info("Using SyncBatchNorm()")

    # Trainloader
    ## ここで dataset 作ってる、
    dataloader, dataset = create_dataloader(
        train_path,
        imgsz,
        batch_size,
        gs,
        opt,
        hyp=hyp,
        augment=True,
        cache=opt.cache_images,
        rect=opt.rect,
        rank=rank,
        world_size=opt.world_size,
        workers=opt.workers,
        image_weights=opt.image_weights,
        quad=opt.quad,
        prefix=colorstr("train: "),
    )
    mlc = np.concatenate(dataset.labels, 0)[:, 0].max()  # max label class
    nb = len(dataloader)  # number of batches
    assert (
        mlc < nc
    ), "Label class %g exceeds nc=%g in %s. Possible class labels are 0-%g" % (
        mlc,
        nc,
        opt.data,
        nc - 1,
    )

    # Process 0
    if rank in [-1, 0]:
        testloader = create_dataloader(
            test_path,
            imgsz_test,
            batch_size * 2,
            gs,
            opt,  # testloader
            hyp=hyp,
            cache=opt.cache_images and not opt.notest,
            rect=True,
            rank=-1,
            world_size=opt.world_size,
            workers=opt.workers,
            pad=0.5,
            prefix=colorstr("val: "),
        )[0]

        if not opt.resume:
            labels = np.concatenate(dataset.labels, 0)
            c = torch.tensor(labels[:, 0])  # classes
            # cf = torch.bincount(c.long(), minlength=nc) + 1.  # frequency
            # model._initialize_biases(cf.to(device))
            if plots:
                plot_labels(labels, names, save_dir, loggers)
                if tb_writer:
                    tb_writer.add_histogram("classes", c, 0)

            # Anchors
            if not opt.noautoanchor:
                check_anchors(dataset,
                              model=model,
                              thr=hyp["anchor_t"],
                              imgsz=imgsz)
            model.half().float()  # pre-reduce anchor precision

    # DDP mode
    if cuda and rank != -1:
        ## 変更ポイント3、ラップ
        model = DDP(
            model,
            device_ids=[opt.local_rank],
            output_device=opt.local_rank,
            # nn.MultiheadAttention incompatibility with DDP https://github.com/pytorch/pytorch/issues/26698
            find_unused_parameters=any(
                isinstance(layer, nn.MultiheadAttention)
                for layer in model.modules()),
        )

    # Model parameters
    hyp["box"] *= 3.0 / nl  # scale to layers
    hyp["cls"] *= nc / 80.0 * 3.0 / nl  # scale to classes and layers
    hyp["obj"] *= (imgsz / 640)**2 * 3.0 / nl  # scale to image size and layers
    hyp["label_smoothing"] = opt.label_smoothing
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # iou loss ratio (obj_loss = 1.0 or iou)
    model.class_weights = (
        labels_to_class_weights(dataset.labels, nc).to(device) * nc
    )  # attach class weights
    model.names = names

    # Start training
    t0 = time.time()
    nw = max(round(hyp["warmup_epochs"] * nb),
             1000)  # number of warmup iterations, max(3 epochs, 1k iterations)
    # nw = min(nw, (epochs - start_epoch) / 2 * nb)  # limit warmup to < 1/2 of training
    maps = np.zeros(nc)  # mAP per class
    results = (0, 0, 0, 0, 0, 0, 0
               )  # P, R, [email protected], [email protected], val_loss(box, obj, cls)
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    compute_loss = ComputeLoss(model)  # init loss class
    logger.info(f"Image sizes {imgsz} train, {imgsz_test} test\n"
                f"Using {dataloader.num_workers} dataloader workers\n"
                f"Logging results to {save_dir}\n"
                f"Starting training for {epochs} epochs...")
    for epoch in range(
            start_epoch, epochs
    ):  # epoch ------------------------------------------------------------------
        print(epoch)
        model.train()

        # Update image weights (optional)
        if opt.image_weights:
            # Generate indices
            if rank in [-1, 0]:
                cw = (model.class_weights.cpu().numpy() * (1 - maps)**2 / nc
                      )  # class weights
                iw = labels_to_image_weights(dataset.labels,
                                             nc=nc,
                                             class_weights=cw)  # image weights
                dataset.indices = random.choices(
                    range(dataset.n), weights=iw,
                    k=dataset.n)  # rand weighted idx
            # Broadcast if DDP
            if rank != -1:
                indices = (torch.tensor(dataset.indices)
                           if rank == 0 else torch.zeros(dataset.n)).int()
                dist.broadcast(indices, 0)
                if rank != 0:
                    dataset.indices = indices.cpu().numpy()

        # Update mosaic border
        # b = int(random.uniform(0.25 * imgsz, 0.75 * imgsz + gs) // gs * gs)
        # dataset.mosaic_border = [b - imgsz, -b]  # height, width borders

        mloss = torch.zeros(4, device=device)  # mean losses
        if rank != -1:
            dataloader.sampler.set_epoch(epoch)
        pbar = enumerate(dataloader)
        logger.info(
            ("\n" + "%10s" * 8) % ("Epoch", "gpu_mem", "box", "obj", "cls",
                                   "total", "labels", "img_size"))
        if rank in [-1, 0]:
            pbar = tqdm(pbar, total=nb)  # progress bar
        optimizer.zero_grad()
        for i, (
                imgs,
                targets,
                paths,
                _,
        ) in (
                pbar
        ):  # batch -------------------------------------------------------------
            ni = i + nb * epoch  # number integrated batches (since train start)
            print(f'batch: {ni}')
            imgs = (imgs.to(device, non_blocking=True).float() / 255.0
                    )  # uint8 to float32, 0-255 to 0.0-1.0

            # Warmup
            if ni <= nw:
                xi = [0, nw]  # x interp
                # model.gr = np.interp(ni, xi, [0.0, 1.0])  # iou loss ratio (obj_loss = 1.0 or iou)
                accumulate = max(
                    1,
                    np.interp(ni, xi, [1, nbs / total_batch_size]).round())
                for j, x in enumerate(optimizer.param_groups):
                    # bias lr falls from 0.1 to lr0, all other lrs rise from 0.0 to lr0
                    x["lr"] = np.interp(
                        ni,
                        xi,
                        [
                            hyp["warmup_bias_lr"] if j == 2 else 0.0,
                            x["initial_lr"] * lf(epoch),
                        ],
                    )
                    if "momentum" in x:
                        x["momentum"] = np.interp(
                            ni, xi, [hyp["warmup_momentum"], hyp["momentum"]])

            # Multi-scale
            if opt.multi_scale:
                sz = random.randrange(imgsz * 0.5,
                                      imgsz * 1.5 + gs) // gs * gs  # size
                sf = sz / max(imgs.shape[2:])  # scale factor
                if sf != 1:
                    ns = [math.ceil(x * sf / gs) * gs for x in imgs.shape[2:]
                          ]  # new shape (stretched to gs-multiple)
                    imgs = F.interpolate(imgs,
                                         size=ns,
                                         mode="bilinear",
                                         align_corners=False)

            # Forward
            with amp.autocast(enabled=cuda):
                pred = model(imgs)  # forward
                loss, loss_items = compute_loss(
                    pred, targets.to(device))  # loss scaled by batch_size
                if rank != -1:
                    loss *= (opt.world_size
                             )  # gradient averaged between devices in DDP mode
                if opt.quad:
                    loss *= 4.0

            # Backward
            scaler.scale(loss).backward()

            # Optimize
            if ni % accumulate == 0:
                scaler.step(optimizer)  # optimizer.step
                scaler.update()
                optimizer.zero_grad()
                if ema:
                    ema.update(model)

            # Print
            if rank in [-1, 0]:
                mloss = (mloss * i + loss_items) / (i + 1
                                                    )  # update mean losses
                mem = "%.3gG" % (torch.cuda.memory_reserved() / 1e9
                                 if torch.cuda.is_available() else 0)  # (GB)
                s = ("%10s" * 2 + "%10.4g" * 6) % (
                    "%g/%g" % (epoch, epochs - 1),
                    mem,
                    *mloss,
                    targets.shape[0],
                    imgs.shape[-1],
                )
                pbar.set_description(s)

                # Plot
                if plots and ni < 3:
                    f = save_dir / f"train_batch{ni}.jpg"  # filename
                    Thread(target=plot_images,
                           args=(imgs, targets, paths, f),
                           daemon=True).start()
                    #if tb_writer:
                    #    tb_writer.add_graph(
                    #        torch.jit.trace(model, imgs, strict=False), []
                    #    )  # add model graph
                    #    # tb_writer.add_image(f, result, dataformats='HWC', global_step=epoch)
                elif plots and ni == 10 and wandb_logger.wandb:
                    wandb_logger.log({
                        "Mosaics": [
                            wandb_logger.wandb.Image(str(x), caption=x.name)
                            for x in save_dir.glob("train*.jpg") if x.exists()
                        ]
                    })

            # end batch ------------------------------------------------------------------------------------------------
        # end epoch ----------------------------------------------------------------------------------------------------

        # Scheduler
        lr = [x["lr"] for x in optimizer.param_groups]  # for tensorboard
        scheduler.step()

        # DDP process 0 or single-GPU
        # 変更ポイント5 の dist.get_rank()==0 はここで反映されている
        if rank in [-1, 0]:
            # mAP
            ema.update_attr(
                model,
                include=[
                    "yaml", "nc", "hyp", "gr", "names", "stride",
                    "class_weights"
                ],
            )
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                wandb_logger.current_epoch = epoch + 1
                results, maps, times = test.test(
                    data_dict,
                    batch_size=batch_size * 2,
                    imgsz=imgsz_test,
                    model=ema.ema,
                    single_cls=opt.single_cls,
                    dataloader=testloader,
                    save_dir=save_dir,
                    verbose=nc < 50 and final_epoch,
                    plots=plots and final_epoch,
                    wandb_logger=wandb_logger,
                    compute_loss=compute_loss,
                    is_coco=is_coco,
                )

            # Write
            with open(results_file, "a") as f:
                f.write(s + "%10.4g" * 7 % results +
                        "\n")  # append metrics, val_loss

            # Log
            tags = [
                "train/box_loss",
                "train/obj_loss",
                "train/cls_loss",  # train loss
                "metrics/precision",
                "metrics/recall",
                "metrics/mAP_0.5",
                "metrics/mAP_0.5:0.95",
                "val/box_loss",
                "val/obj_loss",
                "val/cls_loss",  # val loss
                "x/lr0",
                "x/lr1",
                "x/lr2",
            ]  # params
            for x, tag in zip(list(mloss[:-1]) + list(results) + lr, tags):
                if tb_writer:
                    tb_writer.add_scalar(tag, x, epoch)  # tensorboard
                if wandb_logger.wandb:
                    wandb_logger.log({tag: x})  # W&B

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # weighted combination of [P, R, [email protected], [email protected]]
            if fi > best_fitness:
                best_fitness = fi
            wandb_logger.end_epoch(best_result=best_fitness == fi)

            # Save model
            if (not opt.nosave) or (final_epoch and not opt.evolve):  # if save
                ckpt = {
                    "epoch":
                    epoch,
                    "best_fitness":
                    best_fitness,
                    "training_results":
                    results_file.read_text(),
                    "model":
                    deepcopy(
                        model.module if is_parallel(model) else model).half(),
                    "ema":
                    deepcopy(ema.ema).half(),
                    "updates":
                    ema.updates,
                    "optimizer":
                    optimizer.state_dict(),
                    "wandb_id":
                    wandb_logger.wandb_run.id if wandb_logger.wandb else None,
                }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                if wandb_logger.wandb:
                    if ((epoch + 1) % opt.save_period == 0
                            and not final_epoch) and opt.save_period != -1:
                        wandb_logger.log_model(last.parent,
                                               opt,
                                               epoch,
                                               fi,
                                               best_model=best_fitness == fi)
                del ckpt

        # end epoch ----------------------------------------------------------------------------------------------------
    # end training
    if rank in [-1, 0]:
        # Plots
        if plots:
            plot_results(save_dir=save_dir)  # save as results.png
            if wandb_logger.wandb:
                files = [
                    "results.png",
                    "confusion_matrix.png",
                    *[f"{x}_curve.png" for x in ("F1", "PR", "P", "R")],
                ]
                wandb_logger.log({
                    "Results": [
                        wandb_logger.wandb.Image(str(save_dir / f), caption=f)
                        for f in files if (save_dir / f).exists()
                    ]
                })
        # Test best.pt
        logger.info("%g epochs completed in %.3f hours.\n" %
                    (epoch - start_epoch + 1, (time.time() - t0) / 3600))
        if opt.data.endswith("coco.yaml") and nc == 80:  # if COCO
            for m in (last,
                      best) if best.exists() else (last):  # speed, mAP tests
                results, _, _ = test.test(
                    opt.data,
                    batch_size=batch_size * 2,
                    imgsz=imgsz_test,
                    conf_thres=0.001,
                    iou_thres=0.7,
                    model=attempt_load(m, device).half(),
                    single_cls=opt.single_cls,
                    dataloader=testloader,
                    save_dir=save_dir,
                    save_json=True,
                    plots=False,
                    is_coco=is_coco,
                )

        # Strip optimizers
        final = best if best.exists() else last  # final model
        for f in last, best:
            if f.exists():
                strip_optimizer(f)  # strip optimizers
        if opt.bucket:
            os.system(f"gsutil cp {final} gs://{opt.bucket}/weights")  # upload
        if wandb_logger.wandb and not opt.evolve:  # Log the stripped model
            wandb_logger.wandb.log_artifact(
                str(final),
                type="model",
                name="run_" + wandb_logger.wandb_run.id + "_model",
                aliases=["last", "best", "stripped"],
            )
        wandb_logger.finish_run()
    else:
        dist.destroy_process_group()
    torch.cuda.empty_cache()
    return results
Пример #4
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(colorstr('hyperparameters: ') + ', '.join(f'{k}={v}' for k, v in hyp.items()))
    save_dir, epochs, batch_size, total_batch_size, weights, rank = \
        Path(opt.save_dir), opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank

    # Directories
    wdir = save_dir / 'weights'
    wdir.mkdir(parents=True, exist_ok=True)  # make dir
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    results_file = save_dir / 'results.txt'

    # Save run settings
    with open(save_dir / 'hyp.yaml', 'w') as f:
        yaml.safe_dump(hyp, f, sort_keys=False)
    with open(save_dir / 'opt.yaml', 'w') as f:
        yaml.safe_dump(vars(opt), f, sort_keys=False)

    # Configure
    plots = not opt.evolve  # create plots
    cuda = device.type != 'cpu'
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.safe_load(f)  # data dict
    is_coco = opt.data.endswith('coco.yaml')

    # Logging- Doing this before checking the dataset. Might update data_dict
    loggers = {'wandb': None}  # loggers dict
    if rank in [-1, 0]:
        opt.hyp = hyp  # add hyperparameters
        run_id = torch.load(weights).get('wandb_id') if weights.endswith('.pt') and os.path.isfile(weights) else None
        wandb_logger = WandbLogger(opt, save_dir.stem, run_id, data_dict)
        loggers['wandb'] = wandb_logger.wandb
        data_dict = wandb_logger.data_dict
        if wandb_logger.wandb:
            weights, epochs, hyp = opt.weights, opt.epochs, opt.hyp  # WandbLogger might update weights, epochs if resuming

    nc = 1 if opt.single_cls else int(data_dict['nc'])  # number of classes
    names = ['item'] if opt.single_cls and len(data_dict['names']) != 1 else data_dict['names']  # class names
    assert len(names) == nc, '%g names found for nc=%g dataset in %s' % (len(names), nc, opt.data)  # check

    # modal stage model
    modal_stage_model = None
    if opt.modal_stage_model is not None and opt.modal_stage_model != "":
        modal_ckpt = torch.load(opt.modal_stage_model, map_location=device)
        modal_stage_model = Model(modal_ckpt['model'].yaml, ch=3, nc=nc).to(device)
        state_dict = modal_ckpt['model'].float().state_dict()
        state_dict = intersect_dicts(state_dict, modal_stage_model.state_dict(), exclude=[])
        modal_stage_model.load_state_dict(state_dict, strict=False)
        logger.info('Transferred %g/%g items from %s for modal stage model' % (len(state_dict), len(modal_stage_model.state_dict()), opt.modal_stage_model))
        modal_stage_model.eval()

    # Model
    if modal_stage_model is not None:
        input_ch = 3 + nc
    else:
        input_ch = 3
    pretrained = weights.endswith('.pt')
    if pretrained:
        with torch_distributed_zero_first(rank):
            attempt_download(weights)  # download if not found locally
        ckpt = torch.load(weights, map_location=device)  # load checkpoint
        model = Model(opt.cfg or ckpt['model'].yaml, ch=input_ch, nc=nc, anchors=hyp.get('anchors')).to(device)  # create
        exclude = ['anchor'] if (opt.cfg or hyp.get('anchors')) and not opt.resume else []  # exclude keys
        state_dict = ckpt['model'].float().state_dict()  # to FP32
        state_dict = intersect_dicts(state_dict, model.state_dict(), exclude=exclude)  # intersect
        model.load_state_dict(state_dict, strict=False)  # load
        logger.info('Transferred %g/%g items from %s' % (len(state_dict), len(model.state_dict()), weights))  # report
    else:
        model = Model(opt.cfg, ch=input_ch, nc=nc, anchors=hyp.get('anchors')).to(device)  # create
    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check
    train_path = data_dict['train']
    val_paths = dict()
    if type(data_dict['val']) == str:
        val_paths[MASTER_VAL_NAME] = data_dict['val']
    elif len(data_dict['val']) == 1:
        val_paths[MASTER_VAL_NAME] = data_dict['val']
    else:
        if MASTER_VAL_NAME not in data_dict['val']:
            raise ValueError(f"When you use multiple validation sets, one MUST be named '{MASTER_VAL_NAME}'. This is the val set" +
                             f" we will use for early stopping/model selection. Your data yaml file ({opt.data}) does NOT " +
                             "conform to this requirement. Please fix it.")
        for k, v in data_dict['val'].items():
            # in this case, the yaml file has several datasets under the key 'val'
            val_paths[k] = v

    # Freeze
    freeze = []  # parameter names to freeze (full or partial)
    for k, v in model.named_parameters():
        v.requires_grad = True  # train all layers
        if any(x in k for x in freeze):
            print('freezing %s' % k)
            v.requires_grad = False

    # Optimizer
    nbs = 64  # nominal batch size
    accumulate = max(round(nbs / total_batch_size), 1)  # accumulate loss before optimizing
    hyp['weight_decay'] *= total_batch_size * accumulate / nbs  # scale weight_decay
    logger.info(f"Scaled weight_decay = {hyp['weight_decay']}")

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_modules():
        if hasattr(v, 'bias') and isinstance(v.bias, nn.Parameter):
            pg2.append(v.bias)  # biases
        if isinstance(v, nn.BatchNorm2d):
            pg0.append(v.weight)  # no decay
        elif hasattr(v, 'weight') and isinstance(v.weight, nn.Parameter):
            pg1.append(v.weight)  # apply decay

    if opt.adam:
        optimizer = optim.Adam(pg0, lr=hyp['lr0'], betas=(hyp['momentum'], 0.999))  # adjust beta1 to momentum
    else:
        optimizer = optim.SGD(pg0, lr=hyp['lr0'], momentum=hyp['momentum'], nesterov=True)

    optimizer.add_param_group({'params': pg1, 'weight_decay': hyp['weight_decay']})  # add pg1 with weight_decay
    optimizer.add_param_group({'params': pg2})  # add pg2 (biases)
    logger.info('Optimizer groups: %g .bias, %g conv.weight, %g other' % (len(pg2), len(pg1), len(pg0)))
    del pg0, pg1, pg2

    # Scheduler https://arxiv.org/pdf/1812.01187.pdf
    # https://pytorch.org/docs/stable/_modules/torch/optim/lr_scheduler.html#OneCycleLR
    if opt.linear_lr:
        lf = lambda x: (1 - x / (epochs - 1)) * (1.0 - hyp['lrf']) + hyp['lrf']  # linear
    else:
        lf = one_cycle(1, hyp['lrf'], epochs)  # cosine 1->hyp['lrf']
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # EMA
    ema = ModelEMA(model) if rank in [-1, 0] else None

    # Resume
    start_epoch, best_fitness = 0, 0.0
    if pretrained:
        # Optimizer
        if ckpt['optimizer'] is not None:
            optimizer.load_state_dict(ckpt['optimizer'])
            best_fitness = ckpt['best_fitness']

        # EMA
        if ema and ckpt.get('ema'):
            ema.ema.load_state_dict(ckpt['ema'].float().state_dict())
            ema.updates = ckpt['updates']

        # Results
        if ckpt.get('training_results') is not None:
            results_file.write_text(ckpt['training_results'])  # write results.txt

        # Epochs
        start_epoch = ckpt['epoch'] + 1
        if opt.resume:
            assert start_epoch > 0, '%s training to %g epochs is finished, nothing to resume.' % (weights, epochs)
        if epochs < start_epoch:
            logger.info('%s has been trained for %g epochs. Fine-tuning for %g additional epochs.' %
                        (weights, ckpt['epoch'], epochs))
            epochs += ckpt['epoch']  # finetune additional epochs

        del ckpt, state_dict

    # Image sizes
    gs = max(int(model.stride.max()), 32)  # grid size (max stride)
    nl = model.model[-1].nl  # number of detection layers (used for scaling hyp['obj'])
    imgsz, imgsz_test = [check_img_size(x, gs) for x in opt.img_size]  # verify imgsz are gs-multiples

    # DP mode
    if cuda and rank == -1 and torch.cuda.device_count() > 1:
        model = torch.nn.DataParallel(model)

    # SyncBatchNorm
    if opt.sync_bn and cuda and rank != -1:
        model = torch.nn.SyncBatchNorm.convert_sync_batchnorm(model).to(device)
        logger.info('Using SyncBatchNorm()')

    # Trainloader
    dataloader, dataset = create_dataloader(train_path, imgsz, batch_size, gs, opt,
                                            hyp=hyp, augment=True, cache=opt.cache_images, rect=opt.rect, rank=rank,
                                            world_size=opt.world_size, workers=opt.workers,
                                            image_weights=opt.image_weights, quad=opt.quad, prefix=colorstr('train: '))
    if dataset.single_labelset:
        mlc = np.concatenate(dataset.labels, 0)[:, 0].max()  # max label class
    else:
        mlc = np.concatenate([dataset.labels[i]['amodal'] for i in range(len(dataset.labels))], 0)[:, 0].max()  # max label class, as taken from *amodal* labels
    nb = len(dataloader)  # number of batches
    assert mlc < nc, 'Label class %g exceeds nc=%g in %s. Possible class labels are 0-%g' % (mlc, nc, opt.data, nc - 1)

    # Process 0
    if rank in [-1, 0]:
        val_loaders = dict()
        for k, v in val_paths.items():
            val_loaders[k] = create_dataloader(v, imgsz_test, batch_size * 2, gs, opt,
                                           hyp=hyp, cache=opt.cache_images and not opt.notest, rect=True, rank=-1,
                                           world_size=opt.world_size, workers=opt.workers,
                                           pad=0.5, prefix=colorstr(f"val/{k}: "))[0]

        if not opt.resume:
            if dataset.single_labelset:
                labels = np.concatenate(dataset.labels, 0)
            else:
                # use the class distribution from the amodal labels for this generated histogram
                labels = np.concatenate([dataset.labels[i]['amodal'] for i in range(len(dataset.labels))], 0)
            c = torch.tensor(labels[:, 0])  # classes
            # cf = torch.bincount(c.long(), minlength=nc) + 1.  # frequency
            # model._initialize_biases(cf.to(device))
            if plots:
                plot_labels(labels, names, save_dir, loggers)
                if tb_writer:
                    tb_writer.add_histogram('classes', c, 0)

            # Anchors
            if not opt.noautoanchor:
                check_anchors(dataset, model=model, thr=hyp['anchor_t'], imgsz=imgsz)
            model.half().float()  # pre-reduce anchor precision

    # DDP mode
    if cuda and rank != -1:
        model = DDP(model, device_ids=[opt.local_rank], output_device=opt.local_rank,
                    # nn.MultiheadAttention incompatibility with DDP https://github.com/pytorch/pytorch/issues/26698
                    find_unused_parameters=any(isinstance(layer, nn.MultiheadAttention) for layer in model.modules()))

    # Model parameters
    hyp['box'] *= 3. / nl  # scale to layers
    hyp['cls'] *= nc / 80. * 3. / nl  # scale to classes and layers
    hyp['obj'] *= (imgsz / 640) ** 2 * 3. / nl  # scale to image size and layers
    hyp['label_smoothing'] = opt.label_smoothing
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # iou loss ratio (obj_loss = 1.0 or iou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(device) * nc  # attach class weights
    model.names = names

    # Start training
    t0 = time.time()
    nw = max(round(hyp['warmup_epochs'] * nb), 1000)  # number of warmup iterations, max(3 epochs, 1k iterations)
    # nw = min(nw, (epochs - start_epoch) / 2 * nb)  # limit warmup to < 1/2 of training
    maps = np.zeros(nc)  # mAP per class
    results = (0, 0, 0, 0, 0, 0, 0)  # P, R, [email protected], [email protected], val_loss(box, obj, cls)
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    compute_loss = ComputeLoss(model)  # init loss class

    # init tensorboardx tags
    train_tags = ['train/box_loss', 'train/obj_loss', 'train/cls_loss']
    lr_tags = ['x/lr0', 'x/lr1', 'x/lr2']

    logger.info(f'Image sizes {imgsz} train, {imgsz_test} test\n'
                f'Using {dataloader.num_workers} dataloader workers\n'
                f'Logging results to {save_dir}\n'
                f'Starting training for {epochs} epochs...')
    for epoch in range(start_epoch, epochs):  # epoch ------------------------------------------------------------------
        model.train()

        # Update image weights (optional)
        if opt.image_weights:
            if not dataset.single_labelset:
                raise NotImplementedError("We don't support image weighting in the modal/amodal label case yet, but it can be added.")
            # Generate indices
            if rank in [-1, 0]:
                cw = model.class_weights.cpu().numpy() * (1 - maps) ** 2 / nc  # class weights
                iw = labels_to_image_weights(dataset.labels, nc=nc, class_weights=cw)  # image weights
                dataset.indices = random.choices(range(dataset.n), weights=iw, k=dataset.n)  # rand weighted idx
            # Broadcast if DDP
            if rank != -1:
                indices = (torch.tensor(dataset.indices) if rank == 0 else torch.zeros(dataset.n)).int()
                dist.broadcast(indices, 0)
                if rank != 0:
                    dataset.indices = indices.cpu().numpy()

        # Update mosaic border
        # b = int(random.uniform(0.25 * imgsz, 0.75 * imgsz + gs) // gs * gs)
        # dataset.mosaic_border = [b - imgsz, -b]  # height, width borders

        mloss = torch.zeros(4, device=device)  # mean losses
        if rank != -1:
            dataloader.sampler.set_epoch(epoch)
        pbar = enumerate(dataloader)
        logger.info(('\n' + '%10s' * 8) % ('Epoch', 'gpu_mem', 'box', 'obj', 'cls', 'total', 'labels', 'img_size'))
        if rank in [-1, 0]:
            pbar = tqdm(pbar, total=nb)  # progress bar
        optimizer.zero_grad()
        for i, (imgs, targets, paths, _) in pbar:  # batch -------------------------------------------------------------
            ni = i + nb * epoch  # number integrated batches (since train start)
            imgs = imgs.to(device, non_blocking=True).float() / 255.0  # uint8 to float32, 0-255 to 0.0-1.0

            """
            In the modal/amodal use case, 'targets' is a dictionary of tensors, so you should choose
            targets['modal'] or targets['amodal'] depending on your needs.
            """
            # TODO: change this logic when ready!
            if isinstance(targets, dict):
                targets = targets['amodal']

            if modal_stage_model is not None:
                with torch.no_grad():
                    img_shape = (imgs.shape[2], imgs.shape[3])
                    boxes, _ = modal_stage_model.forward(imgs)
                    pixel_map = predicted_bboxes_to_pixel_map(boxes, img_shape)
                    imgs = torch.cat([imgs, pixel_map], dim=1)


            # Warmup
            if ni <= nw:
                xi = [0, nw]  # x interp
                # model.gr = np.interp(ni, xi, [0.0, 1.0])  # iou loss ratio (obj_loss = 1.0 or iou)
                accumulate = max(1, np.interp(ni, xi, [1, nbs / total_batch_size]).round())
                for j, x in enumerate(optimizer.param_groups):
                    # bias lr falls from 0.1 to lr0, all other lrs rise from 0.0 to lr0
                    x['lr'] = np.interp(ni, xi, [hyp['warmup_bias_lr'] if j == 2 else 0.0, x['initial_lr'] * lf(epoch)])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(ni, xi, [hyp['warmup_momentum'], hyp['momentum']])

            # Multi-scale
            if opt.multi_scale:
                sz = random.randrange(imgsz * 0.5, imgsz * 1.5 + gs) // gs * gs  # size
                sf = sz / max(imgs.shape[2:])  # scale factor
                if sf != 1:
                    ns = [math.ceil(x * sf / gs) * gs for x in imgs.shape[2:]]  # new shape (stretched to gs-multiple)
                    imgs = F.interpolate(imgs, size=ns, mode='bilinear', align_corners=False)

            # Forward
            with amp.autocast(enabled=cuda):
                pred = model(imgs)  # forward
                loss, loss_items = compute_loss(pred, targets.to(device))  # loss scaled by batch_size
                if rank != -1:
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode
                if opt.quad:
                    loss *= 4.

            # Backward
            scaler.scale(loss).backward()

            # Optimize
            if ni % accumulate == 0:
                scaler.step(optimizer)  # optimizer.step
                scaler.update()
                optimizer.zero_grad()
                if ema:
                    ema.update(model)

            # Print
            if rank in [-1, 0]:
                mloss = (mloss * i + loss_items) / (i + 1)  # update mean losses
                mem = '%.3gG' % (torch.cuda.memory_reserved() / 1E9 if torch.cuda.is_available() else 0)  # (GB)
                s = ('%10s' * 2 + '%10.4g' * 6) % (
                    '%g/%g' % (epoch, epochs - 1), mem, *mloss, targets.shape[0], imgs.shape[-1])
                pbar.set_description(s)

                # Plot
                if plots and ni < 3:
                    f = save_dir / f'train_batch{ni}.jpg'  # filename
                    Thread(target=plot_images, args=(imgs, targets, paths, f), daemon=True).start()
                    # if tb_writer:
                    #     tb_writer.add_image(f, result, dataformats='HWC', global_step=epoch)
                    #     tb_writer.add_graph(torch.jit.trace(model, imgs, strict=False), [])  # add model graph
                elif plots and ni == 10 and wandb_logger.wandb:
                    wandb_logger.log({"Mosaics": [wandb_logger.wandb.Image(str(x), caption=x.name) for x in
                                                  save_dir.glob('train*.jpg') if x.exists()]})

                # SEND RESULTS TO TBX
                if ni % nb != 0 and ni % opt.tbx_report_train_every_n_batches == 1:
                    # ni % nb != 0 condition to avoid double-logging anything, ... == 1 condition to log information (almost) right away
                    for x, tag in zip(mloss[:-1], train_tags):
                        tb_writer.add_scalar(tag, x, ni)

                    # init tensorboardx 'lr' list
                    lr = [x['lr'] for x in optimizer.param_groups]  # gather learning rates
                    for x, tag in zip(lr, lr_tags):
                        tb_writer.add_scalar(tag, x, ni)

                # TODO: if we want to update val loss more frequently, do it here

            # end batch ------------------------------------------------------------------------------------------------
        # end epoch ----------------------------------------------------------------------------------------------------

        # Scheduler
        lr = [x['lr'] for x in optimizer.param_groups]  # for tensorboard
        scheduler.step()

        # DDP process 0 or single-GPU
        if rank in [-1, 0]:
            # mAP
            ema.update_attr(model, include=['yaml', 'nc', 'hyp', 'gr', 'names', 'stride', 'class_weights'])
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                wandb_logger.current_epoch = epoch + 1
                for val_loader_name in val_loaders.keys():
                    temp_results, temp_maps, temp_times = test.test(data_dict,
                                                     batch_size=batch_size * 2,
                                                     imgsz=imgsz_test,
                                                     model=ema.ema,
                                                     single_cls=opt.single_cls,
                                                     dataloader=val_loaders[val_loader_name],
                                                     save_dir=save_dir,
                                                     verbose=nc < 50 and final_epoch,
                                                     plots=plots and final_epoch,
                                                     wandb_logger=wandb_logger,
                                                     compute_loss=compute_loss,
                                                     is_coco=is_coco,
                                                     modal_stage_model=modal_stage_model)
                    if val_loader_name != MASTER_VAL_NAME:
                        # Log tbx metrics for all non-master validation sets
                        tbx_tags = ['precision', 'recall', 'mAP_0.5', 'mAP_0.5:0.95',
                                    'box_loss', 'obj_loss', 'cls_loss']
                        for x, tag in zip(list(temp_results), tbx_tags):
                            if tb_writer:
                                tb_writer.add_scalar(f"{val_loader_name}/{tag}", x, nb * (epoch + 1))
                            if wandb_logger.wandb:
                                wandb_logger.log({f"{val_loader_name}/{tag}": x})  # W&B
                    else:
                        results = temp_results
                        maps = temp_maps
                        times = temp_times

            # Log
            all_tbx_tags = ['train/box_loss', 'train/obj_loss', 'train/cls_loss',  # train loss
                            # IMPORTANT: when looking at tbx results, the metrics under 'metrics' are calculated on the MASTER VAL SET.
                            'metrics/precision', 'metrics/recall', 'metrics/mAP_0.5', 'metrics/mAP_0.5:0.95',
                            f"{MASTER_VAL_NAME}/box_loss", f"{MASTER_VAL_NAME}/obj_loss", f"{MASTER_VAL_NAME}/cls_loss",  # val loss
                            'x/lr0', 'x/lr1', 'x/lr2']  # params
            for x, tag in zip(list(mloss[:-1]) + list(results) + lr, all_tbx_tags):
                # TBX UPDATES
                if tb_writer:
                    tb_writer.add_scalar(tag, x, nb * (epoch + 1))  # tensorboard
                if wandb_logger.wandb:
                    wandb_logger.log({tag: x})  # W&B

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results + '\n')  # append metrics, val_loss
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' % (results_file, opt.bucket, opt.name))

            # Update best mAP
            fi = fitness(np.array(results).reshape(1, -1))  # weighted combination of [P, R, [email protected], [email protected]]
            if fi > best_fitness:
                best_fitness = fi
            wandb_logger.end_epoch(best_result=best_fitness == fi)

            # Save model
            if (not opt.nosave) or (final_epoch and not opt.evolve):  # if save
                ckpt = {'epoch': epoch,
                        'best_fitness': best_fitness,
                        'training_results': results_file.read_text(),
                        'model': deepcopy(model.module if is_parallel(model) else model).half(),
                        'ema': deepcopy(ema.ema).half(),
                        'updates': ema.updates,
                        'optimizer': optimizer.state_dict(),
                        'wandb_id': wandb_logger.wandb_run.id if wandb_logger.wandb else None}

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                if wandb_logger.wandb:
                    if ((epoch + 1) % opt.save_period == 0 and not final_epoch) and opt.save_period != -1:
                        wandb_logger.log_model(
                            last.parent, opt, epoch, fi, best_model=best_fitness == fi)
                del ckpt

        # end epoch ----------------------------------------------------------------------------------------------------
    # end training
    if rank in [-1, 0]:
        # Plots
        if plots:
            plot_results(save_dir=save_dir)  # save as results.png
            if wandb_logger.wandb:
                files = ['results.png', 'confusion_matrix.png', *[f'{x}_curve.png' for x in ('F1', 'PR', 'P', 'R')]]
                wandb_logger.log({"Results": [wandb_logger.wandb.Image(str(save_dir / f), caption=f) for f in files
                                              if (save_dir / f).exists()]})
        # Test best.pt
        logger.info('%g epochs completed in %.3f hours.\n' % (epoch - start_epoch + 1, (time.time() - t0) / 3600))
        if opt.data.endswith('coco.yaml') and nc == 80:  # if COCO
            for m in (last, best) if best.exists() else (last):  # speed, mAP tests
                results, _, _ = test.test(opt.data,
                                          batch_size=batch_size * 2,
                                          imgsz=imgsz_test,
                                          conf_thres=0.001,
                                          iou_thres=0.7,
                                          model=attempt_load(m, device).half(),
                                          single_cls=opt.single_cls,
                                          dataloader=val_loaders[MASTER_VAL_NAME],
                                          save_dir=save_dir,
                                          save_json=True,
                                          plots=False,
                                          is_coco=is_coco,
                                          modal_stage_model=modal_stage_model)

        # Strip optimizers
        final = best if best.exists() else last  # final model
        for f in last, best:
            if f.exists():
                strip_optimizer(f)  # strip optimizers
        if opt.bucket:
            os.system(f'gsutil cp {final} gs://{opt.bucket}/weights')  # upload
        if wandb_logger.wandb and not opt.evolve:  # Log the stripped model
            wandb_logger.wandb.log_artifact(str(final), type='model',
                                            name='run_' + wandb_logger.wandb_run.id + '_model',
                                            aliases=['last', 'best', 'stripped'])
        wandb_logger.finish_run()
    else:
        dist.destroy_process_group()
    torch.cuda.empty_cache()
    return results