def train(hyp, opt, device, tb_writer=None):
    print(f'Hyperparameters {hyp}')
    log_dir = Path(tb_writer.log_dir) if tb_writer else Path(
        opt.logdir) / 'evolve'  # logging directory
    wdir = str(log_dir / 'weights') + os.sep  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir + 'last.pt'
    best = wdir + 'best.pt'
    results_file = str(log_dir / 'results.txt')
    epochs, batch_size, total_batch_size, weights, rank, loss_name = \
        opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank, opt.loss

    if loss_name == 'ciou':
        loss_fn = compute_loss_ciou
    elif loss_name == 'giou':
        loss_fn = compute_loss_giou
    elif loss_name == 'gioupp':
        loss_fn = compute_loss_gioupp

    # TODO: Use DDP logging. Only the first process is allowed to log.
    # Save run settings
    with open(log_dir / 'hyp.yaml', 'w') as f:
        yaml.dump(hyp, f, sort_keys=False)
    with open(log_dir / 'opt.yaml', 'w') as f:
        yaml.dump(vars(opt), f, sort_keys=False)

    # Configure
    cuda = device.type != 'cpu'
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # model dict
    train_path = data_dict['train']
    test_path = data_dict['val']
    nc, names = (1, ['item']) if opt.single_cls else (int(
        data_dict['nc']), data_dict['names'])  # number classes, 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 = Darknet(opt.cfg).to(device)  # create
        state_dict = {
            k: v
            for k, v in ckpt['model'].items()
            if model.state_dict()[k].numel() == v.numel()
        }
        model.load_state_dict(state_dict, strict=False)
        print('Transferred %g/%g items from %s' %
              (len(state_dict), len(model.state_dict()), weights))  # report
    else:
        model = Darknet(opt.cfg).to(device)  # create

    # 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

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in dict(model.named_parameters()).items():
        if '.bias' in k:
            pg2.append(v)  # biases
        elif 'Conv2d.weight' in k:
            pg1.append(v)  # apply weight_decay
        else:
            pg0.append(v)  # all else

    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)
    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
    lf = lambda x: ((
        (1 + math.cos(x * math.pi / epochs)) / 2)**1.0) * 0.8 + 0.2  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # 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']

        # Results
        if ckpt.get('training_results') is not None:
            with open(results_file, 'w') as file:
                file.write(ckpt['training_results'])  # write results.txt

        # Epochs
        start_epoch = ckpt['epoch'] + 1
        if epochs < start_epoch:
            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
    gs = 32  # grid size (max stride)
    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)
        print('Using SyncBatchNorm()')

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

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

    # Trainloader
    dataloader, dataset = create_dataloader(train_path,
                                            imgsz,
                                            batch_size,
                                            gs,
                                            opt,
                                            hyp=hyp,
                                            augment=True,
                                            cache=opt.cache_images,
                                            rect=opt.rect,
                                            local_rank=rank,
                                            world_size=opt.world_size)
    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)

    # Testloader
    if rank in [-1, 0]:
        ema.updates = start_epoch * nb // accumulate  # set EMA updates ***
        # local_rank is set to -1. Because only the first process is expected to do evaluation.
        testloader = create_dataloader(test_path,
                                       imgsz_test,
                                       batch_size,
                                       gs,
                                       opt,
                                       hyp=hyp,
                                       augment=False,
                                       cache=opt.cache_images,
                                       rect=True,
                                       local_rank=-1,
                                       world_size=opt.world_size)[0]

    # Model parameters
    hyp['cls'] *= nc / 80.  # scale coco-tuned hyp['cls'] to current dataset
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device)  # attach class weights
    model.names = names

    # Class frequency
    if rank in [-1, 0]:
        labels = np.concatenate(dataset.labels, 0)
        c = torch.tensor(labels[:, 0])  # classes
        # cf = torch.bincount(c.long(), minlength=nc) + 1.
        # model._initialize_biases(cf.to(device))
        plot_labels(labels, save_dir=log_dir)
        if tb_writer:
            tb_writer.add_histogram('classes', c, 0)

        # Check anchors
        #if not opt.noautoanchor:
        #    check_anchors(dataset, model=model, thr=hyp['anchor_t'], imgsz=imgsz)

    # Start training
    t0 = time.time()
    nw = max(3 * nb,
             1e3)  # 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', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    if rank in [0, -1]:
        print('Image sizes %g train, %g test' % (imgsz, imgsz_test))
        print('Using %g dataloader workers' % dataloader.num_workers)
        print('Starting training for %g epochs...' % epochs)
    # torch.autograd.set_detect_anomaly(True)
    for epoch in range(
            start_epoch, epochs
    ):  # epoch ------------------------------------------------------------------
        model.train()

        # Update image weights (optional)
        if dataset.image_weights:
            # Generate indices
            if rank in [-1, 0]:
                w = model.class_weights.cpu().numpy() * (
                    1 - maps)**2  # class weights
                image_weights = labels_to_image_weights(dataset.labels,
                                                        nc=nc,
                                                        class_weights=w)
                dataset.indices = random.choices(
                    range(dataset.n), weights=image_weights,
                    k=dataset.n)  # rand weighted idx
            # Broadcast if DDP
            if rank != -1:
                indices = torch.zeros([dataset.n], dtype=torch.int)
                if rank == 0:
                    indices[:] = torch.from_tensor(dataset.indices,
                                                   dtype=torch.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)
        if rank in [-1, 0]:
            print(
                ('\n' + '%10s' * 8) % ('Epoch', 'gpu_mem', 'GIoU', 'obj',
                                       'cls', 'total', 'targets', 'img_size'))
            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])  # giou loss ratio (obj_loss = 1.0 or giou)
                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,
                        [0.1 if j == 2 else 0.0, x['initial_lr'] * lf(epoch)])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(ni, xi,
                                                  [0.9, 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)

            # Autocast
            with amp.autocast(enabled=cuda):
                # Forward
                pred = model(imgs)

                # Loss
                loss, loss_items = compute_loss(pred, targets.to(device),
                                                model)  # scaled by batch_size
                if rank != -1:
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode
                # if not torch.isfinite(loss):
                #     print('WARNING: non-finite loss, ending training ', loss_items)
                #     return results

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

            # Optimize
            if ni % accumulate == 0:
                scaler.step(optimizer)  # optimizer.step
                scaler.update()
                optimizer.zero_grad()
                if ema is not None:
                    ema.update(model)

            # Print
            if rank in [-1, 0]:
                if loss_items:
                    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 ni < 3:
                        f = str(log_dir /
                                ('train_batch%g.jpg' % ni))  # filename
                        result = plot_images(images=imgs,
                                             targets=targets,
                                             paths=paths,
                                             fname=f)
                        if tb_writer and result is not None:
                            tb_writer.add_image(f,
                                                result,
                                                dataformats='HWC',
                                                global_step=epoch)
                            # tb_writer.add_graph(model, imgs)  # add model to tensorboard

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

        # Scheduler
        scheduler.step()

        # DDP process 0 or single-GPU
        if rank in [-1, 0]:
            # mAP
            if ema is not None:
                ema.update_attr(model)
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                results, maps, times = test.test(
                    opt.data,
                    batch_size=batch_size,
                    imgsz=imgsz_test,
                    save_json=final_epoch
                    and opt.data.endswith(os.sep + 'coco.yaml'),
                    model=ema.ema.module
                    if hasattr(ema.ema, 'module') else ema.ema,
                    single_cls=opt.single_cls,
                    dataloader=testloader,
                    save_dir=log_dir,
                    compute_loss=loss_fn)

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Tensorboard
            if tb_writer:
                if loss_items:
                    tags = [
                        'train/giou_loss', 'train/obj_loss', 'train/cls_loss',
                        'metrics/precision', 'metrics/recall',
                        'metrics/mAP_0.5', 'metrics/mAP_0.5:0.95',
                        'val/giou_loss', 'val/obj_loss', 'val/cls_loss'
                    ]
                    for x, tag in zip(list(mloss[:-1]) + list(results), tags):
                        tb_writer.add_scalar(tag, x, epoch)
                else:
                    tags = [
                        "train/" + loss_name + "_loss", 'metrics/precision',
                        'metrics/recall', 'metrics/mAP_0.5',
                        'metrics/mAP_0.5:0.95', "val/" + loss_name + "_loss"
                    ]
                    for x, tag in zip(list(mloss) + list(results), tags):
                        tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, 'r') as f:  # create checkpoint
                    ckpt = {
                        'epoch':
                        epoch,
                        'best_fitness':
                        best_fitness,
                        'training_results':
                        f.read(),
                        'model':
                        ema.ema.module.state_dict()
                        if hasattr(ema, 'module') else ema.ema.state_dict(),
                        'optimizer':
                        None if final_epoch else optimizer.state_dict()
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if epoch >= (epochs - 5):
                    torch.save(ckpt,
                               last.replace('.pt', '_{:03d}.pt'.format(epoch)))
                if (best_fitness == fi) and not final_epoch:
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    if rank in [-1, 0]:
        # Strip optimizers
        n = ('_'
             if len(opt.name) and not opt.name.isnumeric() else '') + opt.name
        fresults, flast, fbest = 'results%s.txt' % n, wdir + 'last%s.pt' % n, wdir + 'best%s.pt' % n
        for f1, f2 in zip([wdir + 'last.pt', wdir + 'best.pt', 'results.txt'],
                          [flast, fbest, fresults]):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                ispt = f2.endswith('.pt')  # is *.pt
                strip_optimizer(f2) if ispt else None  # strip optimizer
                os.system('gsutil cp %s gs://%s/weights' % (
                    f2, opt.bucket)) if opt.bucket and ispt else None  # upload
        # Finish
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        print('%g epochs completed in %.3f hours.\n' %
              (epoch - start_epoch + 1, (time.time() - t0) / 3600))

    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results
Exemple #2
0
def train(hyp, device):
    init_seeds(1)
    cuda = device.type != 'cpu'

    # v5 Model
    weights = './weights/ckpt_model_599_800_0.07873.pt'
    model = attempt_load(weights, map_location=device)

    # load MNN Model
    model_file = './weights/20201231_exp25_599_800_forT_bs128_320x320.mnn'
    net = nn.load_module_from_file(model_file, for_training=True)
    nn.compress.train_quant(net, quant_bits=8)
    mnn_opt = MNN.optim.SGD(5e-6, 0.9, 0)
    mnn_opt.append(net.parameters)
    MNNF.set_thread_number(32)
    net.train(True)

    # Image sizes
    gs = 32  # grid size (max stride)
    imgsz = 320
    batch_size = 128  # verify imgsz are gs-multiples
    stride = [8, 16, 32]
    train_path = '/home/sysman/gate_Sample/VOCdevkit/VOC2017/ImageSets/train_5th_add.txt'
    opt = ''
    f = open('20210104_quan_train.txt', 'w')

    # Trainloader
    dataloader, dataset = create_dataloader(train_path,
                                            imgsz,
                                            batch_size,
                                            gs,
                                            opt,
                                            hyp=hyp,
                                            augment=True,
                                            cache=False,
                                            rect=False,
                                            rank=-1,
                                            world_size=1,
                                            workers=32)

    for epoch in range(
            5
    ):  # epoch ------------------------------------------------------------------
        t0 = time.time()
        total_loss = 0
        # mnn_opt.learning_rate = learning_rate_scheduler(mnn_opt.learning_rate, epoch)
        for i, (imgs, targets, paths, _) in enumerate(
                dataloader
        ):  # batch -------------------------------------------------------------
            t1 = time.time()
            imgs = imgs.to(device, non_blocking=True).float() / 255.0
            # data_image1 = imgs[0].cpu()
            # images_t3 = tf.ToPILImage()(data_image1)
            # images_t3.show()
            # Forward

            bs, c, h, w = imgs.shape

            # 20201231 by zlf
            # MNN forward

            data = MNNF.const(imgs.flatten().tolist(), [bs, 3, 320, 320],
                              MNNF.data_format.NCHW)
            predict = net.forward(data)
            predict.read()
            p1 = MNNF.Var.read(predict)
            p1 = torch.tensor(p1).cuda()
            x1, x2, x3 = torch.split(p1, [4800, 1200, 300], 1)

            x1 = x1.view(-1, 3, 109, 40, 40).permute(0, 1, 3, 4,
                                                     2).contiguous()
            x2 = x2.view(-1, 3, 109, 20, 20).permute(0, 1, 3, 4,
                                                     2).contiguous()
            x3 = x3.view(-1, 3, 109, 10, 10).permute(0, 1, 3, 4,
                                                     2).contiguous()
            x = [x1, x2, x3]

            loss1, loss_items1 = compute_loss(x, targets.to(device), model)
            total_loss += loss_items1[3].item()
            avg_total_loss = total_loss / (i + 1)
            # if i == 0:
            #     print('loss0:',loss1)
            #     print('iou loss:%.4f,obj loss:%.4f,cls loss:%.4f,total:%.4f'%(loss_items1[0].item(),loss_items1[1].item(),loss_items1[2].item(),loss_items1[3].item()))
            loss1 = np.array(loss1.cpu())
            loss1 = MNNF.const(loss1.flatten().tolist(), [1],
                               MNNF.data_format.NCHW)

            # Backward
            mnn_opt.step(loss1)
            t2 = time.time()
            line = '[%d|%d|%d]iou_loss:%.4f,obj_loss:%.4f,cls_loss:%.4f,total:%.4f,mean_total:%.4f,time:%.3f' % (
                epoch, i, len(dataloader) - 1, loss_items1[0].item(),
                loss_items1[1].item(), loss_items1[2].item(),
                loss_items1[3].item(), avg_total_loss, (t2 - t1))
            # print("[%d|%d|%d]train loss:%.5f,time:%.3f "%(epoch,i,len(dataloader)-1,loss1.read(),(t2-t1)))
            f.write(line + '\n')
            print(line)

        # save model
        file_name = './weights/%d_20201231test.mnn' % epoch
        net.train(False)
        predict = net.forward(MNNF.placeholder([1, 3, 192, 320], MNNF.NC4HW4))
        print("Save to " + file_name)
        MNNF.save([predict], file_name)
        print('Epoch:', (time.time() - t0))

        # end epoch ----------------------------------------------------------------------------------------------------
    # end training
    f.close()
Exemple #3
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(f'Hyperparameters {hyp}')
    # 获取记录训练日志的路径
    # 如果设置进化算法则不会传入tb_writer(则为None),设置一个evolve文件夹作为日志目录
    log_dir = Path(tb_writer.log_dir) if tb_writer else Path(
        opt.logdir) / 'evolve'  # logging directory
    # 设置保存权重的路径
    wdir = log_dir / 'weights'  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    # 设置保存results的路径
    results_file = str(log_dir / 'results.txt')
    # 获取轮次、批次、总批次(涉及到分布式训练)、权重、进程序号(主要用于分布式训练)
    epochs, batch_size, total_batch_size, weights, rank = \
        opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank
    # rank = -1

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

    # Configure
    cuda = (device.type != 'cpu')
    # 设置随机种子
    init_seeds(2 + rank)
    with open(opt.data) as f:  # 加载数据配置信息
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # data dict
    with torch_distributed_zero_first(
            rank):  # torch_distributed_zero_first同步所有进程
        check_dataset(
            data_dict
        )  # check_dataset检查数据集,如果没找到数据集则下载数据集(仅适用于项目中自带的yaml文件数据集)
    # 获取训练集、测试集图片路径
    train_path = data_dict['train']
    test_path = data_dict['val']
    # 获取类别数量和类别名字, 如果设置了opt.single_cls则为一类
    nc, names = (1, ['item']) if opt.single_cls else (int(
        data_dict['nc']), data_dict['names'])  # number classes, 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:  # 如果采用预训练
        # 加载模型,从google云盘中自动下载模型
        # 但通常会下载失败,建议提前下载下来放进weights目录
        with torch_distributed_zero_first(rank):
            attempt_download(weights)  # download if not found locally
        # 加载检查点
        ckpt = torch.load(weights, map_location=device)  # load checkpoint
        if hyp.get('anchors'):
            ckpt['model'].yaml['anchors'] = round(
                hyp['anchors'])  # force autoanchor
        """
                这里模型创建,可通过opt.cfg,也可通过ckpt['model'].yaml
                这里的区别在于是否是resume,resume时会将opt.cfg设为空,则按照ckpt['model'].yaml创建模型;
                这也影响着下面是否除去anchor的key(也就是不加载anchor),如果resume则不加载anchor
                主要是因为保存的模型会保存anchors,有时候用户自定义了anchor之后,再resume,则原来基于coco数据集的anchor就会覆盖自己设定的anchor,
                参考https://github.com/ultralytics/yolov5/issues/459
                所以下面设置了intersect_dicts,该函数就是忽略掉exclude
        """
        model = Model(opt.cfg or ckpt['model'].yaml, ch=3,
                      nc=nc).to(device)  # create
        exclude = ['anchor'] if opt.cfg or hyp.get('anchors') 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
        # 显示加载预训练权重的的键值对和创建模型的键值对
        # 如果设置了resume,则会少加载两个键值对(anchors,anchor_grid)
        logger.info(
            'Transferred %g/%g items from %s' %
            (len(state_dict), len(model.state_dict()), weights))  # report
    else:
        # 创建模型, ch为输入图片通道
        model = Model(opt.cfg, ch=3, nc=nc).to(device)  # create

    # Freeze
    """
        冻结模型层,设置冻结层名字即可
        具体可以查看https://github.com/ultralytics/yolov5/issues/679
        但作者不鼓励冻结层,因为他的实验当中显示冻结层不能获得更好的性能,参照:https://github.com/ultralytics/yolov5/pull/707
        并且作者为了使得优化参数分组可以正常进行,在下面将所有参数的requires_grad设为了True
        其实这里只是给一个freeze的示例
    """
    freeze = [
        '',
    ]  # parameter names to freeze (full or partial)
    if any(freeze):
        for k, v in model.named_parameters():
            # print(k,v)
            if any(x in k for x in freeze):
                print('freezing %s' % k)
                v.requires_grad = False

    # Optimizer
    """
        nbs为模拟的batch_size; 
        就比如默认的话上面设置的opt.batch_size为16,这个nbs就为64,
        也就是模型梯度累积了64/16=4(accumulate)次之后
        再更新一次模型,变相的扩大了batch_size
    """
    nbs = 64  # nominal batch size
    accumulate = max(round(nbs / total_batch_size),
                     1)  # accumulate loss before optimizing   accumulate = 4
    # 根据accumulate设置权重衰减系数
    hyp['weight_decay'] *= total_batch_size * accumulate / nbs  # scale weight_decay

    # 将模型分成三组(weight、bn, bias, 其他所有参数)优化
    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_parameters():
        # print(k)
        v.requires_grad = True
        if '.bias' in k:
            pg2.append(v)  # biases
        elif '.weight' in k and '.bn' not in k:
            pg1.append(v)  # apply weight decay
        else:
            pg0.append(v)  # all else

    # 选用优化器,并设置pg0组的优化方式
    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)
    # 设置weight、bn的优化方式
    optimizer.add_param_group({
        'params': pg1,
        'weight_decay': hyp['weight_decay']
    })  # add pg1 with weight_decay
    # 设置biases的优化方式
    optimizer.add_param_group({'params': pg2})  # add pg2 (biases)
    # 打印优化信息
    logger.info('Optimizer groups: %g .bias, %g conv.weight, %g other' %
                (len(pg2), len(pg1), len(pg0)))
    del pg0, pg1, pg2

    # 设置学习率衰减,这里为余弦退火方式进行衰减
    # 就是根据以下公式lf,epoch和超参数hyp['lrf']进行衰减
    # Scheduler https://arxiv.org/pdf/1812.01187.pdf
    # https://pytorch.org/docs/stable/_modules/torch/optim/lr_scheduler.html#OneCycleLR
    lf = lambda x: ((1 + math.cos(x * math.pi / epochs)) / 2) * (1 - hyp[
        'lrf']) + hyp['lrf']  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # Resume
    # 初始化开始训练的epoch和最好的结果
    # best_fitness是以[0.0, 0.0, 0.1, 0.9]为系数并乘以[精确度, 召回率, [email protected], [email protected]:0.95]再求和所得
    # 根据best_fitness来保存best.pt
    start_epoch, best_fitness = 0, 0.0
    if pretrained:
        # Optimizer
        # 加载优化器与 best_fitness
        if ckpt['optimizer'] is not None:
            optimizer.load_state_dict(ckpt['optimizer'])
            best_fitness = ckpt['best_fitness']

        # Results
        # 加载训练结果result.txt
        if ckpt.get('training_results') is not None:
            with open(results_file, 'w') as file:
                file.write(ckpt['training_results'])  # write results.txt

        # Epochs
        # 加载训练的轮次
        # print(ckpt['epoch'])
        start_epoch = ckpt['epoch'] + 1  # ckpt['epoch'] = -1
        """
                如果resume,则备份权重
                尽管目前resume能够近似100%成功的起作用了,参照:https://github.com/ultralytics/yolov5/pull/756
                但为了防止resume时出现其他问题,把之前的权重覆盖了,所以这里进行备份,参照:https://github.com/ultralytics/yolov5/pull/765
        """
        if opt.resume:
            assert start_epoch > 0, '%s training to %g epochs is finished, nothing to resume.' % (
                weights, epochs)
            shutil.copytree(wdir, wdir.parent /
                            f'weights_backup_epoch{start_epoch - 1}'
                            )  # save previous weights
        """
                如果新设置epochs小于加载的epoch,
                则视新设置的epochs为需要再训练的轮次数而不再是总的轮次数
        """
        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
    # 获取模型总步长和模型输入图片分辨率
    gs = int(max(model.stride))  # grid size (max stride)
    # 检查输入图片分辨率确保能够整除总步长gs
    imgsz, imgsz_test = [check_img_size(x, gs) for x in opt.img_size
                         ]  # verify imgsz are gs-multiples
    # imgsz, imgsz_test 都是640

    # DP mode
    # 分布式训练,参照:https://github.com/ultralytics/yolov5/issues/475
    # DataParallel模式,仅支持单机多卡
    # rank为进程编号, 这里应该设置为rank=-1则使用DataParallel模式
    # rank=-1且gpu数量=1时,不会进行分布式
    if cuda and rank == -1 and torch.cuda.device_count() > 1:
        model = torch.nn.DataParallel(model)  # 执行了

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

    # Exponential moving average 指数滑动平均,或指数加权平均
    # 为模型创建EMA指数滑动平均,如果GPU进程数大于1,则不创建
    ema = ModelEMA(model) if rank in [-1, 0] else None

    # DDP mode
    # 如果rank不等于-1,则使用DistributedDataParallel模式
    # local_rank为gpu编号,rank为进程,例如rank=3,local_rank=0 表示第 3 个进程内的第 1 块 GPU。
    if cuda and rank != -1:
        model = DDP(model,
                    device_ids=[opt.local_rank],
                    output_device=opt.local_rank)

    # Trainloader
    # 创建训练集dataloader
    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)
    """
        获取标签中最大的类别值,并于类别数作比较
        如果小于类别数则表示有问题
    """
    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]:
        # 更新ema模型的updates参数,保持ema的平滑性
        ema.updates = start_epoch * nb // accumulate  # set EMA updates
        # 创建测试集dataloader
        testloader = create_dataloader(test_path,
                                       imgsz_test,
                                       total_batch_size,
                                       gs,
                                       opt,
                                       hyp=hyp,
                                       augment=False,
                                       cache=opt.cache_images
                                       and not opt.notest,
                                       rect=True,
                                       rank=-1,
                                       world_size=opt.world_size,
                                       workers=opt.workers)[0]  # testloader

        if not opt.resume:
            # 将所有样本的标签拼接到一起shape为(total, 5),统计后做可视化
            labels = np.concatenate(dataset.labels, 0)
            # 获得所有样本的类别
            c = torch.tensor(labels[:, 0])  # classes
            # cf = torch.bincount(c.long(), minlength=nc) + 1.  # frequency
            # model._initialize_biases(cf.to(device))

            # 根据上面的统计对所有样本的类别,中心点xy位置,长宽wh做可视化
            plot_labels(labels, save_dir=log_dir)
            if tb_writer:
                # tb_writer.add_hparams(hyp, {})  # causes duplicate https://github.com/ultralytics/yolov5/pull/384
                tb_writer.add_histogram('classes', c, 0)
            # Anchors
            """
                    计算默认锚点anchor与数据集标签框的长宽比值
                    标签的长h宽w与anchor的长h_a宽w_a的比值, 即h/h_a, w/w_a都要在(1/hyp['anchor_t'], hyp['anchor_t'])是可以接受的
                    如果标签框满足上面条件的数量小于总数的99%,则根据k-mean算法聚类新的锚点anchor
            """
            if not opt.noautoanchor:
                check_anchors(dataset,
                              model=model,
                              thr=hyp['anchor_t'],
                              imgsz=imgsz)

    # Model parameters
    # 根据自己数据集的类别数设置分类损失的系数
    hyp['cls'] *= nc / 80.  # scale coco-tuned hyp['cls'] to current dataset
    # 设置类别数,超参数
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    """
        设置giou的值在objectness loss中做标签的系数, 使用代码如下
        tobj[b, a, gj, gi] = (1.0 - model.gr) + model.gr * giou.detach().clamp(0).type(tobj.dtype)
        这里model.gr=1,也就是说完全使用标签框与预测框的giou值来作为该预测框的objectness标签
    """
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    # 根据labels初始化图片采样权重
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device)  # attach class weights
    # 获取类别的名字
    model.names = names

    # Start training
    t0 = time.time()
    # 获取热身训练的迭代次数
    nw = max(round(hyp['warmup_epochs'] * nb),
             1e3)  # number of warmup iterations, max(3 epochs, 1k iterations)
    # nw = min(nw, (epochs - start_epoch) / 2 * nb)  # limit warmup to < 1/2 of training
    # 初始化mAP和results
    maps = np.zeros(nc)  # mAP per class
    results = (
        0, 0, 0, 0, 0, 0, 0
    )  # 'P', 'R', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'
    """
        设置学习率衰减所进行到的轮次,
        目的是打断训练后,--resume接着训练也能正常的衔接之前的训练进行学习率衰减
    """
    scheduler.last_epoch = start_epoch - 1  # do not move
    # 通过torch1.6自带的api设置混合精度训练
    scaler = amp.GradScaler(enabled=cuda)
    """
        打印训练和测试输入图片分辨率
        加载图片时调用的cpu进程数
        从哪个epoch开始训练
        """
    logger.info(
        'Image sizes %g train, %g test\nUsing %g dataloader workers\nLogging results to %s\n'
        'Starting training for %g epochs...' %
        (imgsz, imgsz_test, dataloader.num_workers, log_dir, epochs))
    for epoch in range(
            start_epoch, epochs
    ):  # epoch ------------------------------------------------------------------
        model.train()

        # Update image weights (optional)
        if opt.image_weights:
            # Generate indices
            """
                如果设置进行图片采样策略,
                则根据前面初始化的图片采样权重model.class_weights以及maps配合每张图片包含的类别数
                通过random.choices生成图片索引indices从而进行采样
            """
            if rank in [-1, 0]:
                cw = model.class_weights.cpu().numpy() * (
                    1 - maps)**2  # 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
            # 如果是DDP模式,则广播采样策略
            if rank != -1:
                indices = (torch.tensor(dataset.indices)
                           if rank == 0 else torch.zeros(dataset.n)).int()
                # 广播索引到其他group
                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

        # 初始化训练时打印的平均损失信息
        mloss = torch.zeros(4, device=device)  # mean losses
        if rank != -1:
            # DDP模式下打乱数据, ddp.sampler的随机采样数据是基于epoch+seed作为随机种子,
            # 每次epoch不同,随机种子就不同
            dataloader.sampler.set_epoch(epoch)

        pbar = enumerate(dataloader)
        logger.info(
            ('\n' + '%10s' * 8) % ('Epoch', 'gpu_mem', 'GIoU', 'obj', 'cls',
                                   'total', 'targets', 'img_size'))
        if rank in [-1, 0]:
            # tqdm 创建进度条,方便训练时 信息的展示
            pbar = tqdm(pbar, total=nb)  # progress bar

        optimizer.zero_grad()

        for i, (
                imgs, targets, paths, _
        ) in pbar:  # batch -------------------------------------------------------------
            # 计算迭代的次数iteration
            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
            """
                热身训练(前nw次迭代)
                在前nw次迭代中,根据以下方式选取accumulate和学习率
            """
            if ni <= nw:
                xi = [0, nw]  # x interp
                # model.gr = np.interp(ni, xi, [0.0, 1.0])  # giou loss ratio (obj_loss = 1.0 or giou)
                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
                    """
                        bias的学习率从0.1下降到基准学习率lr*lf(epoch),
                        其他的参数学习率从0增加到lr*lf(epoch).
                        lf为上面设置的余弦退火的衰减函数
                    """
                    x['lr'] = np.interp(ni, xi, [
                        hyp['warmup_bias_lr'] if j == 2 else 0.0,
                        x['initial_lr'] * lf(epoch)
                    ])
                    # 动量momentum也从0.9慢慢变到hyp['momentum'](default=0.937)
                    if 'momentum' in x:
                        x['momentum'] = np.interp(
                            ni, xi, [hyp['warmup_momentum'], hyp['momentum']])

            # Multi-scale
            # 设置多尺度训练,从imgsz * 0.5, imgsz * 1.5 + gs随机选取尺寸
            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
            # 混合精度
            with amp.autocast(enabled=cuda):
                pred = model(imgs)  # forward 前向传播
                # Loss
                # 计算损失,包括分类损失,objectness损失,框的回归损失
                # loss为总损失值,loss_items为一个元组,包含分类损失,objectness损失,框的回归损失和总损失
                loss, loss_items = compute_loss(
                    pred, targets.to(device),
                    model)  # loss scaled by batch_size
                if rank != -1:
                    # 平均不同gpu之间的梯度
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode

            # Backward
            # 反向传播
            scaler.scale(loss).backward()

            # Optimize
            # 模型反向传播accumulate次之后再根据累积的梯度更新一次参数
            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]:
                # 打印显存,进行的轮次,损失,target的数量和图片的size等信息
                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])
                # 进度条显示以上信息
                pbar.set_description(s)

                # Plot
                # 将前三次迭代batch的标签框在图片上画出来并保存
                if ni < 3:
                    f = str(log_dir / ('train_batch%g.jpg' % ni))  # filename
                    result = plot_images(images=imgs,
                                         targets=targets,
                                         paths=paths,
                                         fname=f)
                    if tb_writer and result is not None:
                        tb_writer.add_image(f,
                                            result,
                                            dataformats='HWC',
                                            global_step=epoch)
                        # tb_writer.add_graph(model, imgs)  # add model to tensorboard

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

        # Scheduler
        # 进行学习率衰减
        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
            if ema:
                # 更新EMA的属性
                # 添加include的属性
                ema.update_attr(
                    model,
                    include=['yaml', 'nc', 'hyp', 'gr', 'names', 'stride'])
            # 判断该epoch是否为最后一轮
            final_epoch = epoch + 1 == epochs
            # 对测试集进行测试,计算mAP等指标
            # 测试时使用的是EMA模型
            if not opt.notest or final_epoch:  # Calculate mAP
                if final_epoch:  # replot predictions
                    [
                        os.remove(x) for x in glob.glob(
                            str(log_dir / 'test_batch*_pred.jpg'))
                        if os.path.exists(x)
                    ]
                results, maps, times = test.test(opt.data,
                                                 batch_size=total_batch_size,
                                                 imgsz=imgsz_test,
                                                 model=ema.ema,
                                                 single_cls=opt.single_cls,
                                                 dataloader=testloader,
                                                 save_dir=log_dir)

            # Write
            # 将指标写入result.txt
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            # 如果设置opt.bucket, 上传results.txt到谷歌云盘
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Tensorboard
            # 添加指标,损失等信息到tensorboard显示
            if tb_writer:
                tags = [
                    'train/giou_loss',
                    'train/obj_loss',
                    'train/cls_loss',  # train loss
                    'metrics/precision',
                    'metrics/recall',
                    'metrics/mAP_0.5',
                    'metrics/mAP_0.5:0.95',
                    'val/giou_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):
                    tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            # 更新best_fitness
            fi = fitness(np.array(results).reshape(
                1, -1))  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            """
                保存模型,还保存了epoch,results,optimizer等信息,
                optimizer将不会在最后一轮完成后保存
                model保存的是EMA的模型
            """
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, 'r') as f:  # create checkpoint
                    ckpt = {
                        'epoch':
                        epoch,
                        'best_fitness':
                        best_fitness,
                        'training_results':
                        f.read(),
                        'model':
                        ema.ema,
                        'optimizer':
                        None if final_epoch else optimizer.state_dict()
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    if rank in [-1, 0]:
        # Strip optimizers
        """
            模型训练完后,strip_optimizer函数将optimizer从ckpt中去除;
            并且对模型进行model.half(), 将Float32的模型->Float16,
            可以减少模型大小,提高inference速度
        """
        n = opt.name if opt.name.isnumeric() else ''
        fresults, flast, fbest = log_dir / f'results{n}.txt', wdir / f'last{n}.pt', wdir / f'best{n}.pt'
        for f1, f2 in zip([wdir / 'last.pt', wdir / 'best.pt', results_file],
                          [flast, fbest, fresults]):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                if str(f2).endswith('.pt'):  # is *.pt
                    strip_optimizer(f2)  # strip optimizer
                    # 上传结果到谷歌云盘
                    os.system(
                        'gsutil cp %s gs://%s/weights' %
                        (f2, opt.bucket)) if opt.bucket else None  # upload
        # Finish
        # 可视化results.txt文件
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        logger.info('%g epochs completed in %.3f hours.\n' %
                    (epoch - start_epoch + 1, (time.time() - t0) / 3600))

    # 释放显存
    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results
Exemple #4
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(f'Hyperparameters {hyp}')
    log_dir = Path(tb_writer.log_dir) if tb_writer else Path(
        opt.logdir) / 'evolve'  # logging directory
    wdir = log_dir / 'weights'  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    results_file = str(log_dir / 'results.txt')
    epochs, batch_size, total_batch_size, weights, rank = \
        opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank

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

    # Configure
    cuda = device.type != 'cpu'
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # data dict
    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check
    train_path = data_dict['train']
    test_path = data_dict['val']
    nc, names = (1, ['item']) if opt.single_cls else (int(
        data_dict['nc']), data_dict['names'])  # number classes, names
    assert len(names) == nc, '%g names found for nc=%g dataset in %s' % (
        len(names), nc, opt.data)  # check

    # Model
    model = Model(opt.cfg, ch=3, nc=nc).to(device)  # create

    # Freeze
    freeze = [
        '',
    ]  # parameter names to freeze (full or partial)
    if any(freeze):
        for k, v in model.named_parameters():
            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

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_parameters():
        v.requires_grad = True
        if '.bias' in k:
            pg2.append(v)  # biases
        elif '.weight' in k and '.bn' not in k:
            pg1.append(v)  # apply weight decay
        else:
            pg0.append(v)  # all else

    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
    lf = lambda x: ((1 + math.cos(x * math.pi / epochs)) / 2) * (1 - hyp[
        'lrf']) + hyp['lrf']  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)

    # Resume
    start_epoch, best_fitness = 0, 0.0

    # Image sizes
    gs = int(max(model.stride))  # grid size (max stride)
    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()')

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

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

    # 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)
    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]:
        ema.updates = start_epoch * nb // accumulate  # set EMA updates
        testloader = create_dataloader(test_path,
                                       imgsz_test,
                                       total_batch_size,
                                       gs,
                                       opt,
                                       hyp=hyp,
                                       augment=False,
                                       cache=opt.cache_images
                                       and not opt.notest,
                                       rect=True,
                                       rank=-1,
                                       world_size=opt.world_size,
                                       workers=opt.workers)[0]  # testloader

        if not opt.resume:
            labels = np.concatenate(dataset.labels, 0)
            c = torch.tensor(labels[:, 0])  # classes
            plot_labels(labels, save_dir=log_dir)
            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 parameters
    hyp['cls'] *= nc / 80.  # scale coco-tuned hyp['cls'] to current dataset
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device)  # attach class weights
    model.names = names

    # Start training
    t0 = time.time()
    nw = max(round(hyp['warmup_epochs'] * nb),
             1e3)  # 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', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    logger.info(
        'Image sizes %g train, %g test\nUsing %g dataloader workers\nLogging results to %s\n'
        'Starting training for %g epochs...' %
        (imgsz, imgsz_test, dataloader.num_workers, log_dir, 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  # 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()

        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', 'GIoU', 'obj', 'cls',
                                   'total', 'targets', '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
                accumulate = max(
                    1,
                    np.interp(ni, xi, [1, nbs / total_batch_size]).round())
                for j, x in enumerate(optimizer.param_groups):
                    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),
                    model)  # loss scaled by batch_size
                if rank != -1:
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode

            # 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 ni < 3:
                    f = str(log_dir / ('train_batch%g.jpg' % ni))  # filename
                    result = plot_images(images=imgs,
                                         targets=targets,
                                         paths=paths,
                                         fname=f)
                    if tb_writer and result is not None:
                        tb_writer.add_image(f,
                                            result,
                                            dataformats='HWC',
                                            global_step=epoch)
                        # tb_writer.add_graph(model, imgs)  # add model to tensorboard

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

        # 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
            if ema:
                ema.update_attr(
                    model,
                    include=['yaml', 'nc', 'hyp', 'gr', 'names', 'stride'])
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                if final_epoch:  # replot predictions
                    [
                        os.remove(x) for x in glob.glob(
                            str(log_dir / 'test_batch*_pred.jpg'))
                        if os.path.exists(x)
                    ]
                results, maps, times = test.test(opt.data,
                                                 batch_size=total_batch_size,
                                                 imgsz=imgsz_test,
                                                 model=ema.ema,
                                                 single_cls=opt.single_cls,
                                                 dataloader=testloader,
                                                 save_dir=log_dir)

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Tensorboard
            if tb_writer:
                tags = [
                    'train/giou_loss',
                    'train/obj_loss',
                    'train/cls_loss',  # train loss
                    'metrics/precision',
                    'metrics/recall',
                    'metrics/mAP_0.5',
                    'metrics/mAP_0.5:0.95',
                    'val/giou_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):
                    tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, 'r') as f:  # create checkpoint
                    ckpt = {
                        'epoch':
                        epoch,
                        'best_fitness':
                        best_fitness,
                        'training_results':
                        f.read(),
                        'model':
                        ema.ema,
                        'optimizer':
                        None if final_epoch else optimizer.state_dict()
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    if rank in [-1, 0]:
        # Strip optimizers
        n = opt.name if opt.name.isnumeric() else ''
        fresults, flast, fbest = log_dir / f'results{n}.txt', wdir / f'last{n}.pt', wdir / f'best{n}.pt'
        for f1, f2 in zip([wdir / 'last.pt', wdir / 'best.pt', results_file],
                          [flast, fbest, fresults]):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                if str(f2).endswith('.pt'):  # is *.pt
                    strip_optimizer(f2)  # strip optimizer
                    os.system(
                        'gsutil cp %s gs://%s/weights' %
                        (f2, opt.bucket)) if opt.bucket else None  # upload
        # Finish
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        logger.info('%g epochs completed in %.3f hours.\n' %
                    (epoch - start_epoch + 1, (time.time() - t0) / 3600))

    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results
Exemple #5
0
def train_aux_for_LCP(cfg, backbone, neck, data_loader, weights, aux_weight,
                      hyp, device, resume, epochs):
    init_seeds()
    batch_size = data_loader.batch_size
    accumulate = 64 // batch_size

    model = Darknet(cfg).to(device)
    model_chkpt = torch.load(weights, map_location=device)
    model.load_state_dict(model_chkpt['model'], strict=True)
    del model_chkpt
    aux_util = AuxNetUtils(model, hyp, backbone, neck, strategy="LCP")
    hook_util = HookUtils()

    start_epoch = 0

    aux_model_list = []
    pg = []
    for layer in aux_util.aux_in_layer:
        aux_model = aux_util.creat_aux_model(layer)
        aux_model.to(device)
        for v in aux_model.parameters():
            pg += [v]
        aux_model_list.append(aux_model)

    optimizer = optim.SGD(pg,
                          lr=hyp['lr0'],
                          momentum=hyp['momentum'],
                          nesterov=True)
    del pg

    if resume:
        chkpt = torch.load(aux_weight, map_location=device)

        for i, layer in enumerate(aux_util.aux_in_layer):
            aux_model_list[i].load_state_dict(chkpt['aux_in{}'.format(layer)],
                                              strict=True)

        if chkpt['optimizer'] is not None:
            optimizer.load_state_dict(chkpt['optimizer'])

        start_epoch = chkpt['epoch'] + 1

    scheduler = lr_scheduler.MultiStepLR(
        optimizer, milestones=[epochs // 3, 2 * epochs // 3], gamma=0.1)
    scheduler.last_epoch = start_epoch - 1

    handles = []  # 结束训练后handle需要回收
    for name, child in model.module_list.named_children():
        if name in aux_util.aux_in_layer:
            handles.append(
                child.register_forward_hook(hook_util.hook_origin_output))

    if device.type != 'cpu' and torch.cuda.device_count() > 1:
        model = nn.parallel.DistributedDataParallel(
            model, find_unused_parameters=True)
        model.yolo_layers = model.module.yolo_layers

    nb = len(data_loader)
    model.nc = 80
    model.hyp = hyp
    model.arc = 'default'
    print('Starting training for %g epochs...' % epochs)
    for epoch in range(start_epoch, epochs):

        for aux_model in aux_model_list:
            aux_model.train()
        print(('\n' + '%10s' * 6) %
              ('Stage', 'Epoch', 'gpu_mem', 'AuxID', 'cls', 'targets'))

        # -----------------start batch-----------------
        pbar = tqdm(enumerate(data_loader), total=nb)
        model.train()
        for i, (imgs, targets, _, _) in pbar:

            if len(targets) == 0:
                continue

            ni = i + nb * epoch
            imgs = imgs.to(device).float(
            ) / 255.0  # uint8 to float32, 0 - 255 to 0.0 - 1.0
            targets = targets.to(device)

            with torch.no_grad():
                prediction = model(imgs)

            hook_util.cat_to_gpu0()
            for aux_idx, aux_model in enumerate(aux_model_list):
                pred, loc_loss = aux_model(
                    hook_util.origin_features['gpu0'][aux_idx], targets,
                    prediction)
                loss = compute_loss_for_LCP(pred, loc_loss, targets)

                loss *= batch_size / 64

                loss.backward()

                mem = torch.cuda.memory_cached(
                ) / 1E9 if torch.cuda.is_available() else 0  # (GB)
                s = ('%10s' * 3 + '%10.3g' * 3) % ('Train Aux', '%g/%g' %
                                                   (epoch, epochs - 1),
                                                   '%.3gG' % mem, aux_idx,
                                                   loss, len(targets))
                pbar.set_description(s)
            # 每个batch后要把hook_out内容清除
            hook_util.clean_hook_out()
            if ni % accumulate == 0:
                optimizer.step()
                optimizer.zero_grad()
        # -----------------end batches-----------------

        scheduler.step()
        final_epoch = epoch + 1 == epochs
        chkpt = {
            'epoch': epoch,
            'optimizer': None if final_epoch else optimizer.state_dict()
        }
        for i, layer in enumerate(aux_util.aux_in_layer):
            chkpt['aux_in{}'.format(layer)] = aux_model_list[i].state_dict()

        torch.save(chkpt, aux_weight)

        torch.save(chkpt, "../weights/LCP/aux-coco.pt")
        del chkpt

        with open("./LCP/aux_result.txt", 'a') as f:
            f.write(s + '\n')

    # 最后要把hook全部删除
    for handle in handles:
        handle.remove()
    torch.cuda.empty_cache()
def init_seeds(seed=0):
    random.seed(seed)
    np.random.seed(seed)
    torch_utils.init_seeds(seed=seed)
                        default=0,
                        help='optional test variable')
    parser.add_argument('--s', type=float, default=0.0001, help='sparity')

    parser.add_argument('--cfg',
                        type=str,
                        default='mul_sparsity/yolov3_5.cfg',
                        help='cfg file path')
    parser.add_argument('--weights-path',
                        type=str,
                        default='mul_sparsity/yolov3_5.weights',
                        help='path to store weights')
    opt = parser.parse_args()
    print(opt, end='\n\n')

    torch_utils.init_seeds()

    torch.cuda.empty_cache()
    train(
        opt.cfg,
        opt.data_config,
        img_size=opt.img_size,
        resume=opt.resume,
        epochs=opt.epochs,
        batch_size=opt.batch_size,
        weights_path=opt.weights_path,
        report=opt.report,
        multi_scale=opt.multi_scale,
        freeze_backbone=opt.freeze,
        var=opt.var,
        s=opt.s,
Exemple #8
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(f'Hyperparameters {hyp}')
    log_dir = Path(tb_writer.log_dir) if tb_writer else Path(
        opt.logdir) / 'evolve'  # logging directory
    log_dir = Path('/home/data/yolov5_pt', log_dir)
    wdir = log_dir / 'weights'  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    results_file = str(log_dir / 'results.txt')
    epochs, batch_size, total_batch_size, weights, rank = \
        opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank

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

    # Configure
    cuda = device.type != 'cpu'
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # data dict
        print(data_dict)
    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check
    train_path = data_dict['train']
    test_path = data_dict['val']
    nc, names = (1, ['item']) if opt.single_cls else (int(
        data_dict['nc']), data_dict['names'])  # number classes, 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
        if hyp.get('anchors'):
            ckpt['model'].yaml['anchors'] = round(
                hyp['anchors'])  # force autoanchor
        model = Model(opt.cfg or ckpt['model'].yaml, ch=3,
                      nc=nc).to(device)  # create
        exclude = ['anchor'] if opt.cfg or hyp.get('anchors') 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).to(device)  # create

    # load MNN Model
    model_file = './weights/20201231_exp25_599_800_forT_bs128_320x320.mnn'
    net = nn.load_module_from_file(model_file, for_training=True)
    nn.compress.train_quant(net, quant_bits=8)
    mnn_opt = MNN.optim.SGD(1e-9, 0.9, 0)
    mnn_opt.append(net.parameters)
    net.train(True)

    # Freeze
    freeze = [
        '',
    ]  # parameter names to freeze (full or partial)
    if any(freeze):
        for k, v in model.named_parameters():
            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

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_parameters():
        v.requires_grad = True
        if '.bias' in k:
            pg2.append(v)  # biases
        elif '.weight' in k and '.bn' not in k:
            pg1.append(v)  # apply weight decay
        else:
            pg0.append(v)  # all else

    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
    lf = lambda x: ((1 + math.cos(x * math.pi / epochs)) / 2) * (1 - hyp[
        'lrf']) + hyp['lrf']  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # 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']

        # Results
        if ckpt.get('training_results') is not None:
            with open(results_file, 'w') as file:
                file.write(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)
            # shutil.copytree(wdir, wdir.parent / f'weights_backup_epoch{start_epoch - 1}')  # save previous weights
        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 = int(max(model.stride))  # grid size (max stride)
    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()')

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

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

    # Trainloader
    t0 = time.time()
    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)
    t1 = time.time()
    print('dataloader is created in {}s'.format(t1 - t0))

    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]:
        ema.updates = start_epoch * nb // accumulate  # set EMA updates
        testloader = create_dataloader(test_path,
                                       imgsz_test,
                                       total_batch_size,
                                       gs,
                                       opt,
                                       hyp=hyp,
                                       augment=False,
                                       cache=opt.cache_images,
                                       rect=True,
                                       rank=-1,
                                       world_size=opt.world_size,
                                       workers=opt.workers)[0]  # testloader

        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))
            plot_labels(labels, save_dir=log_dir)
            if tb_writer:
                # tb_writer.add_hparams(hyp, {})  # causes duplicate https://github.com/ultralytics/yolov5/pull/384
                tb_writer.add_histogram('classes', c, 0)

            # Anchors
            if not opt.noautoanchor:
                check_anchors(dataset,
                              model=model,
                              thr=hyp['anchor_t'],
                              imgsz=imgsz)

    # Model parameters
    hyp['cls'] *= nc / 104.  # scale coco-tuned hyp['cls'] to current dataset
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device)  # attach class weights
    model.names = names

    # Start training
    t0 = time.time()
    nw = max(3 * nb,
             1e3)  # 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', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    logger.info(
        'Image sizes %g train, %g test\nUsing %g dataloader workers\nLogging results to %s\n'
        'Starting training for %g epochs...' %
        (imgsz, imgsz_test, dataloader.num_workers, log_dir, epochs))
    # add by zlf on 20201113
    # write down all the results
    # save_path = '/home/data/yolov5_pt/new_val_work/val_result/20201124_finetune_800/'
    # if not os.path.exists(save_path):
    #     os.makedirs(save_path)
    # count_f = open(save_path+'result_count.txt','w')
    # add by zlf on 20201113

    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  # 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', 'GIoU', 'obj', 'cls',
                                   'total', 'targets', '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])  # giou loss ratio (obj_loss = 1.0 or giou)
                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,
                        [0.1 if j == 2 else 0.0, x['initial_lr'] * lf(epoch)])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(ni, xi,
                                                  [0.9, 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):
                # data_image1 = imgs[0].cpu()
                # images_t3 = tf.ToPILImage()(data_image1)
                # images_t3.show()
                # for n,p in model.named_parameters():
                #     print(p.dtype)
                # pred = model(imgs)

                # 20201231 by zlf
                # MNN forward
                data = MNNF.const(imgs.flatten().tolist(), [128, 3, 320, 320],
                                  MNNF.data_format.NCHW)
                predict = net.forward(data)
                predict.read()
                p1 = MNNF.Var.read(predict)
                print(predict.shape)
                print(predict.size)
                print(predict.dtype)

                p1 = torch.tensor(p1).cuda()
                x1, x2, x3 = torch.split(p1, [4800, 1200, 300], 1)

                x1 = x1.view(-1, 3, 109, 40, 40).permute(0, 1, 3, 4,
                                                         2).contiguous()
                x2 = x2.view(-1, 3, 109, 20, 20).permute(0, 1, 3, 4,
                                                         2).contiguous()
                x3 = x3.view(-1, 3, 109, 10, 10).permute(0, 1, 3, 4,
                                                         2).contiguous()
                x = [x1, x2, x3]

                # by zlf 20201016 now,pred is (bs,327,6,10),
                # but complute loss needs (bs,3,6,10,109)
                # for idx in range(3):
                #     bs, _, ny, nx = pred[idx].shape
                #     pred[idx] = pred[idx].view(bs, 3, 109, ny, nx).permute(0, 1, 3, 4, 2).contiguous()
                # 20201016 by zlf

                # loss, loss_items = compute_loss(pred, targets.to(device), model)
                loss1, loss_items1 = compute_loss(x, targets.to(device), model)
                loss1 = np.array(loss1.cpu())
                loss1 = MNNF.const(loss1.flatten().tolist(), [1],
                                   MNNF.data_format.NCHW)
                # print('loss:',loss)# loss scaled by batch_size
                # if rank != -1:
                #     loss *= opt.world_size  # gradient averaged between devices in DDP mode

            # Backward
            # scaler.scale(loss).backward()
            mnn_opt.step(loss1)

            # 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/%g' % (epoch, epochs - 1,i), mem, *mloss, targets.shape[0], imgs.shape[-1])
            #     pbar.set_description(s)
            #
            #     # Plot
            #     if ni < 3:
            #         f = str(log_dir / ('train_batch%g.jpg' % ni))  # filename
            #         result = plot_images(images=imgs, targets=targets, paths=paths, fname=f)
            #         if tb_writer and result is not None:
            #             tb_writer.add_image(f, result, dataformats='HWC', global_step=epoch)
            # tb_writer.add_graph(model, imgs)  # add model to tensorboard

            # 20201016 by zlf
            # save model
            # with open(results_file, 'a') as f:
            #     f.write(s + '%10.4g' * 7 % results + '\n')
            #
            # with open(results_file, 'r') as f:  # create checkpoint
            #     ckpt = {'epoch': epoch,
            #             'best_fitness': best_fitness,
            #             'training_results': None,
            #             'model': ema.ema,
            #             'optimizer': None}

            # if epoch>120 and (i % 450 == 0) and (i != 0):
            #     torch.save(ckpt, wdir / 'ckpt_model_{}_{}_{}.pt'.format(epoch,i,round((mloss.sum()/2.).item(),5)))
            # add by zlf on 20201113 New Val Project
            # wdir_s = str(wdir)+'/'
            # modelv = ModelV(wdir_s+'ckpt_model_{}_{}_{}.pt'.format(epoch,i,round((mloss.sum()/2.).item(),5)))
            # imgs_dir = '%s_%s/'%(epoch,i)
            # if not os.path.exists(save_path+imgs_dir):
            #     os.mkdir(save_path+imgs_dir)
            # l = val(modelv,'new_val_work/val.txt',
            #         issave=False,
            #         save_path=save_path+imgs_dir,
            #         result_txt=save_path+imgs_dir+'result.txt')
            # result_txt = save_path+imgs_dir+'result.txt'
            # d1, d2, miss_detect, wrong_detect, extra_detect, total_error = check_result(result_txt)
            # line1 = 'model_epoch%s_%s: '%(epoch,i)
            # line2 = '{"total":%d,"miss":%d,"wrong":%d,"extra":%d}'%(total_error,miss_detect,wrong_detect,extra_detect)
            # print(line1+line2)
            # line = line1+line2+'\n'+str(d2)
            # count_f.write(line+'\n')

            # del ckpt
            # end batch ------------------------------------------------------------------------------------------------
        # save model
        file_name = './weights/%d_20201231test.mnn' % epoch
        net.train(False)
        predict = net.forward(MNNF.placeholder([1, 3, 192, 320], MNNF.NC4HW4))
        print("Save to " + file_name)
        MNNF.save([predict], file_name)

        # 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
            if ema:
                ema.update_attr(
                    model,
                    include=['yaml', 'nc', 'hyp', 'gr', 'names', 'stride'])
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                if final_epoch:  # replot predictions
                    [
                        os.remove(x) for x in glob.glob(
                            str(log_dir / 'test_batch*_pred.jpg'))
                        if os.path.exists(x)
                    ]
                results, maps, times = test.test(opt.data,
                                                 batch_size=total_batch_size,
                                                 imgsz=imgsz_test,
                                                 model=ema.ema,
                                                 single_cls=opt.single_cls,
                                                 dataloader=testloader,
                                                 save_dir=log_dir)

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Tensorboard
            if tb_writer:
                tags = [
                    'train/giou_loss',
                    'train/obj_loss',
                    'train/cls_loss',  # train loss
                    'metrics/precision',
                    'metrics/recall',
                    'metrics/mAP_0.5',
                    'metrics/mAP_0.5:0.95',
                    'val/giou_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):
                    tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, 'r') as f:  # create checkpoint
                    ckpt = {
                        'epoch':
                        epoch,
                        'best_fitness':
                        best_fitness,
                        'training_results':
                        None,
                        'model':
                        ema.ema,
                        'optimizer':
                        None if final_epoch else optimizer.state_dict()
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    # best = wdir / 'epoch%d_best.pt'%epoch
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    # count_f.close()

    if rank in [-1, 0]:
        # Strip optimizers
        n = opt.name if opt.name.isnumeric() else ''
        fresults, flast, fbest = log_dir / f'results{n}.txt', wdir / f'last{n}.pt', wdir / f'best{n}.pt'
        for f1, f2 in zip([wdir / 'last.pt', wdir / 'best.pt', results_file],
                          [flast, fbest, fresults]):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                if str(f2).endswith('.pt'):  # is *.pt
                    strip_optimizer(f2)  # strip optimizer
                    os.system(
                        'gsutil cp %s gs://%s/weights' %
                        (f2, opt.bucket)) if opt.bucket else None  # upload
        # Finish
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        logger.info('%g epochs completed in %.3f hours.\n' %
                    (epoch - start_epoch + 1, (time.time() - t0) / 3600))

    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results
Exemple #9
0
                        action='store_true',
                        help='use torch.optim.Adam() optimizer')
    parser.add_argument('--sync-bn',
                        action='store_true',
                        help='use SyncBatchNorm, only available in DDP mode')
    parser.add_argument('--local_rank',
                        type=int,
                        default=-1,
                        help='DDP parameter, do not modify')
    parser.add_argument('--logdir',
                        type=str,
                        default='runs/',
                        help='logging directory')
    opt = parser.parse_args()

    init_seeds(0)  # clw modify

    # Resume
    if opt.resume:
        last = get_latest_run(
        ) if opt.resume == 'get_last' else opt.resume  # resume from most recent run
        if last and not opt.weights:
            print(f'Resuming training from {last}')
        opt.weights = last if opt.resume and not opt.weights else opt.weights
    # if opt.local_rank == -1 or ("RANK" in os.environ and os.environ["RANK"] == "0"):  # clw delete
    #     check_git_status()

    opt.hyp = opt.hyp or ('data/hyp.finetune.yaml'
                          if opt.weights else 'data/hyp.scratch.yaml')
    opt.data, opt.cfg, opt.hyp = check_file(opt.data), check_file(
        opt.cfg), check_file(opt.hyp)  # check files
Exemple #10
0
def train(hyp, opt, device, tb_writer=None):
    print(f'Hyperparameters {hyp}')
    log_dir = Path(tb_writer.log_dir) if tb_writer else Path(
        opt.logdir) / 'evolve'  # logging directory
    wdir = str(log_dir / 'weights') + os.sep  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir + 'last.pt'
    best = wdir + 'best.pt'
    results_file = str(log_dir / 'results.txt')
    epochs, batch_size, total_batch_size, weights, rank = \
        opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank

    # TODO: Use DDP logging. Only the first process is allowed to log.
    # Save run settings
    with open(log_dir / 'hyp.yaml', 'w') as f:
        yaml.dump(hyp, f, sort_keys=False)
    with open(log_dir / 'opt.yaml', 'w') as f:
        yaml.dump(vars(opt), f, sort_keys=False)

    # Configure
    cuda = device.type != 'cpu'
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # model dict
    root_path = data_dict['root']
    train_path = data_dict['train']
    test_emb_path = data_dict['test_emb']
    test_path = data_dict['test']
    nc, names = (1, ['item']) if opt.single_cls else (int(
        data_dict['nc']), data_dict['names'])  # number classes, names
    assert len(names) == nc, '%g names found for nc=%g dataset in %s' % (
        len(names), nc, opt.data)  # check

    # Remove previous results
    if rank in [-1, 0]:
        for f in glob.glob('*_batch*.jpg') + glob.glob(results_file):
            os.remove(f)

    # Create model
    model = Model(opt.cfg, nc=nc).to(device)

    # Image sizes
    gs = int(max(model.stride))  # grid size (max stride)
    imgsz = imgsz_test = [check_img_size(x, gs) for x in opt.img_size
                          ]  # verify imgsz are gs-multiples

    # Optimizer
    nbs = 64  # nominal batch size
    # default DDP implementation is slow for accumulation according to: https://pytorch.org/docs/stable/notes/ddp.html
    # all-reduce operation is carried out during loss.backward().
    # Thus, there would be redundant all-reduce communications in a accumulation procedure,
    # which means, the result is still right but the training speed gets slower.
    # TODO: If acceleration is needed, there is an implementation of allreduce_post_accumulation
    # in https://github.com/NVIDIA/DeepLearningExamples/blob/master/PyTorch/LanguageModeling/BERT/run_pretraining.py
    accumulate = max(round(nbs / total_batch_size),
                     1)  # accumulate loss before optimizing
    hyp['weight_decay'] *= total_batch_size * accumulate / nbs  # scale weight_decay

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_parameters():
        if v.requires_grad:
            if '.bias' in k:
                pg2.append(v)  # biases
            elif '.weight' in k and '.bn' not in k:
                pg1.append(v)  # apply weight decay
            else:
                pg0.append(v)  # all else

    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)
    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
    lf = lambda x: ((
        (1 + math.cos(x * math.pi / epochs)) / 2)**1.0) * 0.8 + 0.2  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)

    # Load Model
    with torch_distributed_zero_first(rank):
        attempt_download(weights)
    start_epoch, best_fitness = 0, 0.0
    if weights.endswith('.pt'):  # pytorch format
        ckpt = torch.load(weights, map_location=device)  # load checkpoint

        # load model
        try:
            exclude = ['anchor']  # exclude keys
            ckpt['model'] = {
                k: v
                for k, v in ckpt['model'].float().state_dict().items()
                if k in model.state_dict() and not any(x in k for x in exclude)
                and model.state_dict()[k].shape == v.shape
            }
            model.load_state_dict(ckpt['model'], strict=False)
            print('Transferred %g/%g items from %s' %
                  (len(ckpt['model']), len(model.state_dict()), weights))
        except KeyError as e:
            s = "%s is not compatible with %s. This may be due to model differences or %s may be out of date. " \
                "Please delete or update %s and try again, or use --weights '' to train from scratch." \
                % (weights, opt.cfg, weights, weights)
            raise KeyError(s) from e

        # load optimizer
        if ckpt['optimizer'] is not None:
            optimizer.load_state_dict(ckpt['optimizer'])
            best_fitness = ckpt['best_fitness']

        # load results
        if ckpt.get('training_results') is not None:
            with open(results_file, 'w') as file:
                file.write(ckpt['training_results'])  # write results.txt

        # epochs
        start_epoch = ckpt['epoch'] + 1
        if epochs < start_epoch:
            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

    # 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)
        print('Using SyncBatchNorm()')

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

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

    # Trainloader
    dataloader, dataset = create_dataloader(root_path,
                                            train_path,
                                            imgsz,
                                            batch_size,
                                            gs,
                                            opt,
                                            hyp=hyp,
                                            augment=True,
                                            cache=opt.cache_images,
                                            rect=opt.rect,
                                            local_rank=rank,
                                            world_size=opt.world_size)
    # Testloader
    testloader = create_dataloader(root_path,
                                   test_path,
                                   imgsz_test,
                                   total_batch_size,
                                   gs,
                                   opt,
                                   hyp=hyp,
                                   augment=False,
                                   cache=opt.cache_images,
                                   rect=True,
                                   local_rank=-1,
                                   world_size=opt.world_size)[0]
    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)

    # Model parameters
    hyp['cls'] *= nc / 80.  # scale coco-tuned hyp['cls'] to current dataset
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device)  # attach class weights
    model.names = names
    # model.nID = dataset.nID

    # Class frequency
    if rank in [-1, 0]:
        labels = np.concatenate(dataset.labels, 0)
        c = torch.tensor(labels[:, 0])  # classes
        plot_labels(labels, save_dir=log_dir)
        if tb_writer:
            # tb_writer.add_hparams(hyp, {})  # causes duplicate https://github.com/ultralytics/yolov5/pull/384
            tb_writer.add_histogram('classes', c, 0)

        # Check anchors
        if not opt.noautoanchor:
            check_anchors(dataset,
                          model=model,
                          thr=hyp['anchor_t'],
                          imgsz=imgsz)

    # Start training
    t0 = time.time()
    nw = max(3 * nb,
             1e3)  # 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', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    if rank in [0, -1]:
        print('Image sizes {} train, {} test'.format(str(imgsz),
                                                     str(imgsz_test)))
        print('Using %g dataloader workers' % dataloader.num_workers)
        print('Starting training for %g epochs...' % epochs)
    # torch.autograd.set_detect_anomaly(True)
    for epoch in range(
            start_epoch, epochs
    ):  # epoch ------------------------------------------------------------------
        model.train()

        mloss = torch.zeros(5, device=device)  # mean losses
        if rank != -1:
            dataloader.sampler.set_epoch(epoch)
        pbar = enumerate(dataloader)
        if rank in [-1, 0]:
            print(('\n' + '%10s' * 8 + '%13s') %
                  ('Epoch', 'gpu_mem', 'GIoU', 'obj', 'cls', 'lid', 'total',
                   'targets', 'img_size'))
            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])  # giou loss ratio (obj_loss = 1.0 or giou)
                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,
                        [0.1 if j == 2 else 0.0, x['initial_lr'] * lf(epoch)])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(ni, xi,
                                                  [0.9, hyp['momentum']])

            # Multi-scale
            if opt.multi_scale and random.random() < 0.5:
                candidate_shapes = [[608, 1088], [480, 864], [320, 576],
                                    [512, 960], [384, 640]]
                curr_shapes = candidate_shapes[random.randint(0, 4)]
                imgs = F.interpolate(imgs,
                                     size=curr_shapes,
                                     mode='bilinear',
                                     align_corners=False)

            # Autocast
            with amp.autocast(enabled=cuda):
                # Forward
                pred_detect, pred_emb = model(imgs)

                # Loss
                loss, loss_items = compute_loss(pred_detect, pred_emb,
                                                targets.to(device),
                                                model)  # scaled by batch_size
                if rank != -1:
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode

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

            # Optimize
            if ni % accumulate == 0:
                scaler.step(optimizer)  # optimizer.step
                scaler.update()
                optimizer.zero_grad()
                if ema is not None:
                    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 +
                     "%10s") % ('%g/%g' % (epoch, epochs - 1), mem, *mloss,
                                targets.shape[0], '     [%g,%g]' %
                                (imgs.shape[-1], imgs.shape[-2]))
                pbar.set_description(s)

                # Plot
                if ni < 3:
                    f = str(log_dir / ('train_batch%g.jpg' % ni))  # filename
                    result = plot_images(images=imgs,
                                         targets=targets,
                                         paths=paths,
                                         fname=f)
                    if tb_writer and result is not None:
                        tb_writer.add_image(f,
                                            result,
                                            dataformats='HWC',
                                            global_step=epoch)
                        # tb_writer.add_graph(model, imgs)  # add model to tensorboard

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

        # Scheduler
        scheduler.step()

        # DDP process 0 or single-GPU
        if rank in [-1, 0]:
            # mAP
            if ema is not None:
                ema.update_attr(
                    model,
                    include=['yaml', 'nc', 'hyp', 'gr', 'names', 'stride'])
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                results, maps, times = test.test(
                    opt.data,
                    batch_size=total_batch_size,
                    imgsz=imgsz_test,
                    save_json=final_epoch
                    and opt.data.endswith(os.sep + 'coco.yaml'),
                    model=ema.ema.module
                    if hasattr(ema.ema, 'module') else ema.ema,
                    single_cls=opt.single_cls,
                    dataloader=testloader,
                    save_dir=log_dir,
                    emb_dim=model.module.emb_dim)

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 8 % results +
                        '\n')  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Tensorboard
            if tb_writer:
                tags = [
                    'train/giou_loss', 'train/obj_loss', 'train/cls_loss',
                    'metrics/precision', 'metrics/recall', 'metrics/mAP_0.5',
                    'metrics/mAP_0.5:0.95', 'val/giou_loss', 'val/obj_loss',
                    'val/cls_loss'
                ]
                for x, tag in zip(list(mloss[:-1]) + list(results), tags):
                    tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, 'r') as f:  # create checkpoint
                    ckpt = {
                        'epoch':
                        epoch,
                        'best_fitness':
                        best_fitness,
                        'training_results':
                        f.read(),
                        'model':
                        ema.ema.module if hasattr(ema, 'module') else ema.ema,
                        'optimizer':
                        None if final_epoch else optimizer.state_dict()
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    if rank in [-1, 0]:
        # Strip optimizers
        n = ('_'
             if len(opt.name) and not opt.name.isnumeric() else '') + opt.name
        fresults, flast, fbest = 'results%s.txt' % n, wdir + 'last%s.pt' % n, wdir + 'best%s.pt' % n
        for f1, f2 in zip([wdir + 'last.pt', wdir + 'best.pt', 'results.txt'],
                          [flast, fbest, fresults]):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                ispt = f2.endswith('.pt')  # is *.pt
                strip_optimizer(f2) if ispt else None  # strip optimizer
                os.system('gsutil cp %s gs://%s/weights' % (
                    f2, opt.bucket)) if opt.bucket and ispt else None  # upload
        # Finish
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        print('%g epochs completed in %.3f hours.\n' %
              (epoch - start_epoch + 1, (time.time() - t0) / 3600))

    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results
Exemple #11
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(f'Hyperparameters {hyp}')

    print("tb_writer.log_dir: ", tb_writer.log_dir)  #resumed的时候可以从这里恢复
    log_dir = Path(tb_writer.log_dir) if tb_writer else Path(
        opt.logdir) / 'evolve'  # logging directory
    wdir = log_dir / 'weights'  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    print("log_dir: ", log_dir)
    print("wdir: ", wdir)
    print("last: ", last)
    print("best: ", best)
    results_file = str(log_dir / 'results.txt')
    epochs, batch_size, total_batch_size, weights, rank = \
        opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank
    print("epochs: ", epochs)
    print("batch_size: ", batch_size)
    print("total_batch_size: ", total_batch_size)
    print("weights: ", weights)
    print("rank: ", rank)

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

    # Configure
    cuda = device.type != 'cpu'
    print("cuda: ", cuda)
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # data dict
    print("data_dict: ", data_dict)

    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check

    train_path = data_dict['train']
    test_path = data_dict['val']
    nc, names = (1, ['item']) if opt.single_cls else (int(
        data_dict['nc']), data_dict['names'])  # number classes, 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')
    print("pretrained: ", pretrained)

    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
        """ckpt中,['epoch'], ['best_fitness'], ['training_results'], ['model'], ['optimizer']"""
        # print("ckpt: ", ckpt)
        print(
            "ckpt: ['epoch'], ['best_fitness'], ['training_results'], ['optimizer']: ",
            ckpt['epoch'], ckpt['best_fitness'], ckpt['training_results'],
            ckpt['optimizer'])
        # print("ckpt['model']: ", ckpt['model'])
        # print("ckpt['model'].model: ", ckpt['model'].model)
        # print("ckpt['model'].state_dict(): ", ckpt['model'].state_dict())
        print("ckpt['model'].save: ", ckpt['model'].save)
        print("ckpt['model'].yaml: ", ckpt['model'].yaml)

        print("hyp.get('anchors'): ", hyp.get('anchors'))
        if hyp.get('anchors'):
            ckpt['model'].yaml['anchors'] = round(
                hyp['anchors'])  # force autoanchor

        print("opt.cfg: ", opt.cfg)
        # create, 都为真则取or前面的, 即以opt.cfg中的内容(eg:yolov5s.yaml, yolov5x.yaml...)为主,其次是ckpt['model'].yaml
        model = Model(opt.cfg or ckpt['model'].yaml, ch=3, nc=nc).to(device)
        exclude = (['anchor'] if opt.cfg or hyp.get('anchors') else []
                   )  # exclude keys, 以opt.cfg中的anchor为主,其次是hyp中的
        print("exclude: ", exclude)
        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("state_dict: ", state_dict)
        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).to(device)  # create

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

    # Optimizer
    """当模型梯度累积了(nbs/total_batch_size)次之后,再更新一次模型参数,变相的扩大了batch_size"""
    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

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_parameters():
        v.requires_grad = True
        if '.bias' in k:
            pg2.append(v)  # biases
        elif '.weight' in k and '.bn' not in k:
            pg1.append(v)  # apply weight decay
        else:
            pg0.append(v)  # all else

    #optimizer = optim.Adam(pg0, lr=hyp['lr0'], betas=(hyp['momentum'], 0.999))  # adjust beta1 to momentum
    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

    # 设置学习率衰减,这里为余弦退火方式进行衰减
    # Scheduler https://arxiv.org/pdf/1812.01187.pdf
    # https://pytorch.org/docs/stable/_modules/torch/optim/lr_scheduler.html#OneCycleLR
    lf = lambda x: ((1 + math.cos(x * math.pi / epochs)) / 2) * (1 - hyp[
        'lrf']) + hyp['lrf']  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer,
                                      lr_lambda=lf)  #每个epochs具有一个不同的学习率
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # 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']

        # Results
        if ckpt.get('training_results') is not None:
            with open(results_file, 'w') as file:
                file.write(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)
            shutil.copytree(wdir, wdir.parent /
                            f'weights_backup_epoch{start_epoch - 1}'
                            )  # save previous weights
        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 = int(max(model.stride))  # grid size (max stride)  # 获取模型总步长和模型输入图片分辨率
    imgsz, imgsz_test = [
        check_img_size(x, gs) for x in opt.img_size
    ]  # verify imgsz are gs-multiples  #检查输入图片分辨率是gs=32的整数倍
    print("imgsz: ", imgsz)
    print("imgsz_test: ", imgsz_test)

    # DP mode
    if cuda and rank == -1 and torch.cuda.device_count() > 1:
        print(
            "DP mode..............................................................................."
        )
        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()')

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

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

    # 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)
    print("dataloader: ", dataloader)
    print("dataset: ", dataset)

    mlc = np.concatenate(dataset.labels, 0)[:, 0].max()  # max label class
    assert mlc < nc, 'Label class %g exceeds nc=%g in %s. Possible class labels are 0-%g' % (
        mlc, nc, opt.data, nc - 1)

    nb = len(dataloader)  # number of batches
    print("nb: ", nb)

    # Process 0
    if rank in [-1, 0]:
        ema.updates = start_epoch * nb // accumulate  # set EMA updates
        print("ema.updates: ", ema.updates)
        testloader = create_dataloader(test_path,
                                       imgsz_test,
                                       total_batch_size,
                                       gs,
                                       opt,
                                       hyp=hyp,
                                       augment=False,
                                       cache=opt.cache_images
                                       and not opt.notest,
                                       rect=True,
                                       rank=-1,
                                       world_size=opt.world_size,
                                       workers=opt.workers)[0]  # testloader

        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))
            plot_labels(labels, save_dir=log_dir)
            if tb_writer:
                # tb_writer.add_hparams(hyp, {})  # causes duplicate https://github.com/ultralytics/yolov5/pull/384
                tb_writer.add_histogram('classes', c, 0)

            # Anchors
            if not opt.noautoanchor:
                check_anchors(dataset,
                              model=model,
                              thr=hyp['anchor_t'],
                              imgsz=imgsz)

    # Model parameters
    hyp['cls'] *= nc / 80.  # scale coco-tuned hyp['cls'] to current dataset
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device)  # attach class weights
    model.names = names
    #print("model: ", model)

    # Start training
    t0 = time.time()
    n_warmup = max(
        round(hyp['warmup_epochs'] * nb),
        1e3)  # number of warmup iterations, max(3 epochs, 1k iterations)
    # n_warmup = min(n_warmup, (epochs - start_epoch) / 2 * nb)  # limit warmup to < 1/2 of training
    print("n_warmup: ", n_warmup)

    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)  #混合精度梯度放大模块

    maps = np.zeros(nc)  # mAP per class
    results = (
        0, 0, 0, 0, 0, 0, 0
    )  # 'P', 'R', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'

    logger.info(
        'Image sizes %g train, %g test\nUsing %g dataloader workers\nLogging results to %s\n'
        'Starting training for %g epochs...' %
        (imgsz, imgsz_test, dataloader.num_workers, log_dir, 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  # 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', 'GIoU', 'obj', 'cls',
                                   'total', 'targets', '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 batch)
            imgs = imgs.to(device, non_blocking=True).float(
            ) / 255.0  # uint8 to float32, 0-255 to 0.0-1.0
            # Warmup
            if ni <= n_warmup:
                # model.gr = np.interp(ni, xi, [0.0, 1.0])  # giou loss ratio (obj_loss = 1.0 or giou)
                accumulate = max(
                    1,
                    np.interp(ni, [0, n_warmup],
                              [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, [0, n_warmup], [
                        hyp['warmup_bias_lr'] if j == 2 else 0.0,
                        x['initial_lr'] * lf(epoch)
                    ])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(
                            ni, [0, n_warmup],
                            [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):  #自动混合精度
                pred = model(imgs)  # forward
                loss, loss_items = compute_loss(
                    pred, targets.to(device),
                    model)  # loss scaled by batch_size
                if rank != -1:
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode

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

            # Optimize
            """每accumulate个batch时更新一次, 在n_warmup之内时,accumulate从1逐渐增大到4"""
            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 ni < 3:
                    f = str(log_dir / ('train_batch%g.jpg' % ni))  # filename
                    result = plot_images(images=imgs,
                                         targets=targets,
                                         paths=paths,
                                         fname=f)
                    if tb_writer and result is not None:
                        tb_writer.add_image(f,
                                            result,
                                            dataformats='HWC',
                                            global_step=epoch)
                        # tb_writer.add_graph(model, imgs)  # add model to tensorboard

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

        # 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
            if ema:
                ema.update_attr(
                    model,
                    include=['yaml', 'nc', 'hyp', 'gr', 'names', 'stride'])
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                if final_epoch:  # replot predictions
                    [
                        os.remove(x) for x in glob.glob(
                            str(log_dir / 'test_batch*_pred.jpg'))
                        if os.path.exists(x)
                    ]
                results, maps, times = evaluate.test(
                    opt.data,
                    batch_size=total_batch_size,
                    imgsz=imgsz_test,
                    model=ema.ema,
                    single_cls=opt.single_cls,
                    dataloader=testloader,
                    save_dir=log_dir)

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Tensorboard
            if tb_writer:
                tags = [
                    'train/giou_loss',
                    'train/obj_loss',
                    'train/cls_loss',  # train loss
                    'metrics/precision',
                    'metrics/recall',
                    'metrics/mAP_0.5',
                    'metrics/mAP_0.5:0.95',
                    'val/giou_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):
                    tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, 'r') as f:  # create checkpoint
                    ckpt = {
                        'epoch':
                        epoch,
                        'best_fitness':
                        best_fitness,
                        'training_results':
                        f.read(),
                        'model':
                        ema.ema,
                        'optimizer':
                        None if final_epoch else optimizer.state_dict()
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    if rank in [-1, 0]:
        # Strip optimizers
        n = opt.name if opt.name.isnumeric() else ''
        fresults, flast, fbest = log_dir / f'results{n}.txt', wdir / f'last{n}.pt', wdir / f'best{n}.pt'
        for f1, f2 in zip([wdir / 'last.pt', wdir / 'best.pt', results_file],
                          [flast, fbest, fresults]):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                if str(f2).endswith('.pt'):  # is *.pt
                    strip_optimizer(f2)  # strip optimizer
                    os.system(
                        'gsutil cp %s gs://%s/weights' %
                        (f2, opt.bucket)) if opt.bucket else None  # upload
        # Finish
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        logger.info('%g epochs completed in %.3f hours.\n' %
                    (epoch - start_epoch + 1, (time.time() - t0) / 3600))

    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results
Exemple #12
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(f'Hyperparameters {hyp}')
    log_dir = Path(tb_writer.log_dir) if tb_writer else Path(
        opt.logdir) / 'evolve'  # logging directory
    wdir = log_dir / 'weights'  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir / 'last.pt'
    best = wdir / 'best.pt'
    results_file = str(log_dir / 'results.txt')
    epochs, batch_size, total_batch_size, weights, rank = \
        opt.epochs, opt.batch_size, opt.total_batch_size, opt.weights, opt.global_rank

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

    # Configure
    cuda = device.type != 'cpu'
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # model dict
    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check
    train_path = data_dict['train']
    test_path = data_dict['val']
    nc, names = (1, ['item']) if opt.single_cls else (int(
        data_dict['nc']), data_dict['names'])  # number classes, 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
        # added by jiangrong
        if not opt.resume:
            ckpt['epoch'] = -1
        if opt.nas:
            model = NasModel(opt.cfg,
                             ch=3,
                             nc=nc,
                             nas=opt.nas,
                             nas_stage=opt.nas_stage).to(device)  # create
        else:
            model = Model(opt.cfg or ckpt['model'].yaml, ch=3,
                          nc=nc).to(device)  # create
        exclude = ['anchor'] if opt.cfg 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:
        if opt.nas:
            model = NasModel(opt.cfg,
                             ch=3,
                             nc=nc,
                             nas=opt.nas,
                             nas_stage=opt.nas_stage).to(device)  # create
            if opt.nas_stage == 3:
                # TODO, Remapping with BN Statistics on Width-level
                model.re_organize_middle_weights()
        else:
            model = Model(opt.cfg, ch=3, nc=nc).to(device)  # create

    if opt.nas and opt.nas_stage > 0:
        from models.experimental import attempt_load
        """
            P           R           [email protected]
            0.535       0.835       0.742
            python test.py \
                --weights /workspace/yolov5-v3/yolov5/runs/exp122/weights/best.pt \
                --data ./data/baiguang.yaml \
                --device 1 \
                --conf-thres 0.2
        """
        teacher_model = attempt_load(
            "/workspace/yolov5-v3/yolov5/runs/exp259/weights/best.pt",
            map_location='cuda:1')
        teacher_model.eval()
    # Freeze
    freeze = [
        '',
    ]  # parameter names to freeze (full or partial)
    if any(freeze):
        for k, v in model.named_parameters():
            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

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_parameters():
        v.requires_grad = True
        if '.bias' in k:
            pg2.append(v)  # biases
        elif '.weight' in k and '.bn' not in k:
            pg1.append(v)  # apply weight decay
        else:
            pg0.append(v)  # all else

    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
    lf = lambda x: ((
        (1 + math.cos(x * math.pi / epochs)) / 2)**1.0) * 0.8 + 0.2  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

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

        # Results
        if ckpt.get('training_results') is not None:
            with open(results_file, 'w') as file:
                file.write(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)
            shutil.copytree(wdir, wdir.parent /
                            f'weights_backup_epoch{start_epoch - 1}'
                            )  # save previous weights
        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 = int(max(model.stride))  # grid size (max stride)
    imgsz, imgsz_test = [check_img_size(x, gs) for x in opt.img_size
                         ]  # verify imgsz are gs-multiples

    # DP mode
    # TheModel = model
    if cuda and rank == -1 and torch.cuda.device_count() > 1 and not (
            opt.nas and opt.nas_stage > 0):
        # https://pytorch.org/docs/stable/generated/torch.nn.DataParallel.html
        # >>> net = torch.nn.DataParallel(model, device_ids=[0, 1, 2])
        # >>> output = net(input_var)  # input_var can be on any device, including CPU
        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()')

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

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

    # 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)
    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)

    # Testloader
    if rank in [-1, 0]:
        ema.updates = start_epoch * nb // accumulate  # set EMA updates
        testloader = create_dataloader(
            test_path,
            imgsz_test,
            total_batch_size,
            gs,
            opt,
            hyp=hyp,
            augment=False,
            cache=opt.cache_images,
            rect=True,
            rank=-1,
            world_size=opt.world_size,
            workers=opt.workers)[0]  # only runs on process 0

    # Model parameters
    hyp['cls'] *= nc / 80.  # scale coco-tuned hyp['cls'] to current dataset
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device)  # attach class weights
    model.names = names

    # Class frequency
    if rank in [-1, 0]:
        labels = np.concatenate(dataset.labels, 0)
        c = torch.tensor(labels[:, 0])  # classes
        # cf = torch.bincount(c.long(), minlength=nc) + 1.
        # model._initialize_biases(cf.to(device))
        plot_labels(labels, save_dir=log_dir)
        if tb_writer:
            # tb_writer.add_hparams(hyp, {})  # causes duplicate https://github.com/ultralytics/yolov5/pull/384
            tb_writer.add_histogram('classes', c, 0)

        # Check anchors
        if not opt.noautoanchor:
            check_anchors(dataset,
                          model=model,
                          thr=hyp['anchor_t'],
                          imgsz=imgsz)

    # Start training
    t0 = time.time()
    nw = max(3 * nb,
             1e3)  # 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', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'
    scheduler.last_epoch = start_epoch - 1  # do not move
    # scaler = amp.GradScaler(enabled=cuda)
    logger.info('Image sizes %g train, %g test' % (imgsz, imgsz_test))
    logger.info('Using %g dataloader workers' % dataloader.num_workers)
    logger.info('Starting training for %g epochs...' % epochs)
    # torch.autograd.set_detect_anomaly(True)
    plot_csum = 0
    for epoch in range(
            start_epoch, epochs
    ):  # epoch ------------------------------------------------------------------
        model.train()

        # Update image weights (optional)
        if dataset.image_weights:
            # Generate indices
            if rank in [-1, 0]:
                w = model.class_weights.cpu().numpy() * (
                    1 - maps)**2  # class weights
                image_weights = labels_to_image_weights(dataset.labels,
                                                        nc=nc,
                                                        class_weights=w)
                dataset.indices = random.choices(
                    range(dataset.n), weights=image_weights,
                    k=dataset.n)  # rand weighted idx
            # Broadcast if DDP
            if rank != -1:
                indices = torch.zeros([dataset.n], dtype=torch.int)
                if rank == 0:
                    indices[:] = torch.tensor(dataset.indices, dtype=torch.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', 'GIoU', 'obj', 'cls',
                                   'total', 'targets', '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 -------------------------------------------------------------
            # print(type(targets), targets.size()) #  [[_,classid(start from 0), x,y,w,h (0-1)]]
            # print('---> targets: ', targets)
            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])  # giou loss ratio (obj_loss = 1.0 or giou)
                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,
                        [0.1 if j == 2 else 0.0, x['initial_lr'] * lf(epoch)])
                    if 'momentum' in x:
                        x['momentum'] = np.interp(ni, xi,
                                                  [0.9, 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
            ###### jiangrong, turn off mixed precision ##########
            # with amp.autocast(enabled=cuda):
            if 1 == 1:
                pred = model(imgs)  # forward, format x(bs,3,20,20,80+1+4)
                loss, loss_items = compute_loss(
                    pred, targets.to(device),
                    model)  # loss scaled by batch_size
                if rank != -1:
                    loss *= opt.world_size  # gradient averaged between devices in DDP mode
                # z= []
                # for i in range(TheModel._modules['model'][-1].nl):
                #     bs, _, ny, nx, _ = pred[i].shape
                #     if TheModel._modules['model'][-1].grid[i].shape[2:4] != pred[i].shape[2:4]:
                #         TheModel._modules['model'][-1].grid[i] = TheModel._modules['model'][-1]._make_grid(nx, ny).to(pred[i].device)

                #     y = pred[i].sigmoid()
                #     y[..., 0:2] = (y[..., 0:2] * 2. - 0.5 + TheModel._modules['model'][-1].grid[i].to(pred[i].device)) * TheModel._modules['model'][-1].stride[i]  # xy
                #     y[..., 2:4] = (y[..., 2:4] * 2) ** 2 * TheModel._modules['model'][-1].anchor_grid[i]  # wh
                #     z.append(y.view(bs, -1, TheModel._modules['model'][-1].no))
                # inf_out = torch.cat(z, 1)
                # teacher_pred = non_max_suppression(inf_out, conf_thres=0.2, iou_thres=0.6, merge=False)
                # assert len(teacher_pred) == imgs.size()[0]
                # for i, (det, plot_img) in enumerate(zip(teacher_pred, imgs.detach().cpu().numpy())):
                #     plot_img = np.transpose(plot_img, (1,2,0))
                #     plot_img = np.uint8(plot_img * 255.0)
                #     plot_csum += 1
                #     cv2.imwrite('./tmp/{}.jpg'.format(plot_csum), plot_img)
                #     plot_img = cv2.imread('./tmp/{}.jpg'.format(plot_csum))
                #     for tgt in targets.detach().cpu().numpy():
                #         _, tgt_class_id, c_x, c_y, c_w, c_h = tgt
                #         c_x, c_y, c_w, c_h = float(c_x), float(c_y), float(c_w), float(c_h)
                #         c_x, c_y, c_w, c_h = c_x * plot_img.shape[1], c_y * plot_img.shape[0], c_w * plot_img.shape[1], c_h * plot_img.shape[0]
                #         cv2.rectangle(plot_img, (int(c_x - c_w / 2), int(c_y - c_h / 2)), (int(c_x + c_w / 2), int(c_y + c_h / 2)), (0,0,255), 2)
                #         print('===> ', int(c_x - c_w / 2), int(c_y - c_h / 2), int(c_x + c_w / 2), int(c_y + c_h / 2), tgt_class_id)
                #     if det is not None:
                #         det = det.detach().cpu().numpy()
                #         for each_b in det:
                #             pass
                #             cv2.rectangle(plot_img, (int(each_b[0]), int(each_b[1])), (int(each_b[2]), int(each_b[3])), (255,0,0), 2)
                #             print('---> ', int(each_b[0]), int(each_b[1]), int(each_b[2]), int(each_b[3]), float(each_b[4]), int(each_b[5]))
                #     cv2.imwrite('./tmp/{}.jpg'.format(plot_csum), plot_img)

            if opt.nas and opt.nas_stage > 0:
                teacher_imgs = imgs.to('cuda:1')
                with torch.no_grad():
                    inf_out, _ = teacher_model(teacher_imgs)  # forward
                    # filter by obj confidence 0.05
                    teacher_pred = non_max_suppression_teacher(
                        inf_out, conf_thres=0.05, iou_thres=0.6, merge=False
                    )  # (x1, y1, x2, y2, conf, cls) in resized image size
                    teacher_targets = teacher2targets(teacher_pred,
                                                      teacher_imgs)
                    # print('---> teacher_pred', teacher_pred)
                    # print('---> targets', targets)
                    # print('---> teacher_targets', teacher_targets)
                    # TODO: apply soft label loss
                    teacher_loss, teacher_loss_items = compute_teacher_loss(
                        pred, teacher_targets.to(device),
                        model)  # loss scaled by batch_size
                    # print("===> origin loss", loss, loss_items)
                    # print("===> teacher loss", teacher_loss, teacher_loss_items)
                    teacher_loss_scale = 2.0
                    loss += teacher_loss * teacher_loss_scale
                    loss_items += teacher_loss_items * teacher_loss_scale
                    ########## the targets and teacher predictions are matched, but they both can not be restored to the image, need TODO!! ###########
                    # assert len(teacher_pred) == imgs.size()[0]
                    # for i, (det, plot_img) in enumerate(zip(teacher_pred, imgs.detach().cpu().numpy())):
                    #     plot_img = np.transpose(plot_img, (1,2,0))
                    #     plot_img = np.uint8(plot_img * 255.0)
                    #     plot_csum += 1
                    #     cv2.imwrite('./tmp/{}.jpg'.format(plot_csum), plot_img)
                    #     plot_img = cv2.imread('./tmp/{}.jpg'.format(plot_csum))
                    #     for tgt in targets.detach().cpu().numpy():
                    #         _, tgt_class_id, c_x, c_y, c_w, c_h = tgt
                    #         c_x, c_y, c_w, c_h = float(c_x), float(c_y), float(c_w), float(c_h)
                    #         c_x, c_y, c_w, c_h = c_x * plot_img.shape[1], c_y * plot_img.shape[0], c_w * plot_img.shape[1], c_h * plot_img.shape[0]
                    #         cv2.rectangle(plot_img, (int(c_x - c_w / 2), int(c_y - c_h / 2)), (int(c_x + c_w / 2), int(c_y + c_h / 2)), (0,0,255), 2)
                    #         print('===> ', int(c_x - c_w / 2), int(c_y - c_h / 2), int(c_x + c_w / 2), int(c_y + c_h / 2), tgt_class_id)
                    #     if det is not None:
                    #         det = det.detach().cpu().numpy()
                    #         for each_b in det:
                    #             pass
                    #             cv2.rectangle(plot_img, (int(each_b[0]), int(each_b[1])), (int(each_b[2]), int(each_b[3])), (255,0,0), 2)
                    #             print('---> ', int(each_b[0]), int(each_b[1]), int(each_b[2]), int(each_b[3]), float(each_b[4]), int(each_b[5]))
                    #     cv2.imwrite('./tmp/{}.jpg'.format(plot_csum), plot_img)
            # Backward
            # scaler.scale(loss).backward()
            loss.backward()

            # Optimize
            if ni % accumulate == 0:
                # scaler.step(optimizer)  # optimizer.step
                # scaler.update()
                optimizer.step()
                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 ni < 3:
                    f = str(log_dir / ('train_batch%g.jpg' % ni))  # filename
                    result = plot_images(images=imgs,
                                         targets=targets,
                                         paths=paths,
                                         fname=f)
                    if tb_writer and result is not None:
                        tb_writer.add_image(f,
                                            result,
                                            dataformats='HWC',
                                            global_step=epoch)
                        # tb_writer.add_graph(model, imgs)  # add model to tensorboard

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

        # 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
            if ema:
                ema.update_attr(
                    model,
                    include=['yaml', 'nc', 'hyp', 'gr', 'names', 'stride'])
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                if opt.nas:
                    # only evaluate the super network
                    ema.ema.nas_stage = 0
                results, maps, times = test.test(opt.data,
                                                 batch_size=total_batch_size,
                                                 imgsz=imgsz_test,
                                                 model=ema.ema,
                                                 single_cls=opt.single_cls,
                                                 dataloader=testloader,
                                                 save_dir=log_dir)
                if opt.nas:
                    ema.ema.nas_stage = opt.nas_stage

            # Write
            with open(results_file, 'a') as f:
                f.write(s + '%10.4g' * 7 % results +
                        '\n')  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            if len(opt.name) and opt.bucket:
                os.system('gsutil cp %s gs://%s/results/results%s.txt' %
                          (results_file, opt.bucket, opt.name))

            # Tensorboard
            if tb_writer:
                tags = [
                    'train/giou_loss',
                    'train/obj_loss',
                    'train/cls_loss',  # train loss
                    'metrics/precision',
                    'metrics/recall',
                    'metrics/mAP_0.5',
                    'metrics/mAP_0.5:0.95',
                    'val/giou_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):
                    tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            fi = fitness(np.array(results).reshape(
                1, -1))  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, 'r') as f:  # create checkpoint
                    ckpt = {
                        'epoch':
                        epoch,
                        'best_fitness':
                        best_fitness,
                        'training_results':
                        f.read(),
                        'model':
                        ema.ema,
                        'optimizer':
                        None if final_epoch else optimizer.state_dict()
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    if rank in [-1, 0]:
        # Strip optimizers
        n = ('_'
             if len(opt.name) and not opt.name.isnumeric() else '') + opt.name
        fresults, flast, fbest = 'results%s.txt' % n, wdir / f'last{n}.pt', wdir / f'best{n}.pt'
        for f1, f2 in zip([wdir / 'last.pt', wdir / 'best.pt', 'results.txt'],
                          [flast, fbest, fresults]):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                if str(f2).endswith('.pt'):  # is *.pt
                    strip_optimizer(f2)  # strip optimizer
                    os.system(
                        'gsutil cp %s gs://%s/weights' %
                        (f2, opt.bucket)) if opt.bucket else None  # upload
        # Finish
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        logger.info('%g epochs completed in %.3f hours.\n' %
                    (epoch - start_epoch + 1, (time.time() - t0) / 3600))

    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results
Exemple #13
0
def train(opts_dict, args):
    train_epoch = int(opts_dict['epoch'])
    batch_size = int(opts_dict['batch_size'])
    pretrain_weight = opts_dict['pretrained']
    num_workers = int(opts_dict['workers'])
    data_dir = opts_dict['data_dir']
    crop_size = int(opts_dict['crop_size'])
    learn_rate = float(opts_dict['lr'])
    # if use_cuda:
    init_seeds()
    train_dir = opts_dict['train_dir']
    val_dir = opts_dict['val_dir']
    class_name = opts_dict['class_name']
    class_name = class_name.split(",")
    freeze_layer = opts_dict["freeze_layer"]
    checkpoint_dir = opts_dict["checkpoint"]
    resume = opts_dict["resume"]
    try:
        os.stat(checkpoint_dir)
    except:
        os.mkdir(checkpoint_dir)
    embedding_log = 5

    ###---------------------------------------------------------------###

    # 1.load data
    ## reference https://github.com/tanglang96/DataLoaders_DALI
    pip_train = HybridTrainPipe(batch_size=batch_size,
                                num_threads=num_workers,
                                device_id=args.local_rank,
                                data_dir=data_dir + '/train',
                                crop=crop_size,
                                shard_id=args.local_rank,
                                num_shards=args.world_size)
    pip_val = HybridValPipe(batch_size=batch_size,
                            num_threads=num_workers,
                            device_id=args.local_rank,
                            data_dir=data_dir + '/val',
                            crop=crop_size,
                            size=crop_size,
                            shard_id=args.local_rank,
                            num_shards=args.world_size)

    pip_train.build()
    pip_val.build()
    # train_loader = DALIDataloader(pipeline=pip_train, size=SHIP_IMAGES_NUM_TRAIN, batch_size=batch_size,
    #                               onehot_label=True)
    # val_loader = DALIDataloader(pipeline=pip_val, size=SHIP_IMAGES_NUM_VAL, batch_size=batch_size,
    #                               onehot_label=True)
    train_loader = DALIClassificationIterator(pip_train,
                                              reader_name="Reader",
                                              fill_last_batch=True)
    val_loader = DALIClassificationIterator(pip_val,
                                            reader_name="Reader",
                                            fill_last_batch=False)

    # print("[DALI] train dataloader length: %d" % len(train_loader))## len(train_loader)*batch_size = total_image //8
    # print("[DALI] val dataloader length: %d" % len(val_loader))  ## len(train_loader)*batch_size = total_image //8
    # print('[DALI] start iterate train dataloader')
    # time_start = time.time()
    # for i, data in enumerate(train_loader):  # Using it just like PyTorch dataloader
    #     images = data[0].cuda(non_blocking=True)
    #     labels = data[1].cuda(non_blocking=True)
    # time_end = time.time()
    # train_time = time_end - time_start
    # print('[DALI] iteration time: %fs [train]' % (train_time))

    ###--------------------Pytorch dataloader test------------------###
    # transform_train = trns.Compose([
    #     trns.RandomResizedCrop(crop_size, scale=(0.08, 1.25)),
    #     trns.RandomHorizontalFlip(),
    #     trns.ToTensor(),
    #     trns.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
    # ])
    # train_dst = datasets.ImageFolder(data_dir + '/train', transform_train)
    # train_loader = torch.utils.data.DataLoader(train_dst, batch_size=batch_size, shuffle=True, pin_memory=True,
    #                                            num_workers=num_workers)
    # print("[PyTorch] train dataloader length: %d" % len(train_loader))
    # print('[PyTorch] start iterate train dataloader')
    # time_start = time.time()
    # for i, data in enumerate(train_loader):
    #     images = data[0].cuda(non_blocking=True)
    #     labels = data[1].cuda(non_blocking=True)
    # time_end = time.time()
    # train_time = time_end - time_start
    # print('[PyTorch] iteration time: %fs [train]' % (train_time)

    ###---------------------------------------------------------------###

    # 2.load model

    ###vgg16
    model = models.vgg16(pretrained=False).cuda()
    model.load_state_dict(torch.load("./pretrained_weight/vgg16.pth"))

    num_features = model.classifier[6].in_features
    features = list(model.classifier.children())[:-1]  # Remove last layer
    features.extend([
        nn.Linear(num_features, 1024),
        nn.ReLU(inplace=True),
        nn.Linear(1024, 256),
        nn.ReLU(inplace=True),
        nn.Linear(256, 64),
        nn.ReLU(inplace=True),
        nn.Linear(64, len(class_name))
    ])  # Add our layer with 4 outputs
    model.classifier = nn.Sequential(*features)  # Replace the model classifier

    # model = resnest50(num_classes=1000)
    # model = model.cuda()
    #
    # if pretrain_weight:  ##if have pretrain model
    #     model.load_state_dict(torch.load(pretrain_weight))
    #
    #     num_features = model.fc.in_features
    #     features = list(model.fc.children())[:-1]  # Remove last layer
    #     features.extend([nn.Linear(num_features, 512), nn.ReLU(inplace=True),  nn.Linear(512,128), nn.ReLU(inplace=True), nn.Linear(128, len(class_name))])  # Add our layer with 4 outputs
    #     model.fc = nn.Sequential(*features)  # Replace the model classifier
    #
    # if resume:
    #     num_features = model.fc.in_features
    #     features = list(model.fc.children())[:-1]  # Remove last layer
    #     features.extend([nn.Linear(num_features, 512), nn.ReLU(inplace=True), nn.Linear(512,128), nn.ReLU(inplace=True), nn.Linear(128, len(class_name))])  # Add our layer with 4 outputs
    #     model.fc = nn.Sequential(*features)  # Replace the model classifier
    #     model.load_state_dict(torch.load(resume))

    if freeze_layer:  ##Freeze training for  layers
        ct = 0
        for name, param in model.named_parameters():
            ct += 1
            if ct < int(freeze_layer):
                param.requires_grad_(False)
            print(ct, name, param.requires_grad)

    if used_multi_gpu:
        model = parallel.convert_syncbn_model(model)
    model = model.cuda()
    # model.to(device)
    # summary(model, (3, 224, 224))## if you need summary

    ###---------------------------------------------------------------###
    # 3.set optimizer
    # optimizer = optim.Adam(model.parameters(), lr=learn_rate)
    # scheduler = optim.lr_scheduler.LambdaLR(optimizer, lr_lambda=lambda epoch: 1 / (epoch + 1))

    args.lr = args.lr * float(int(opts_dict['batch_size']) *
                              args.world_size) / 256.  ## if batch size = 256
    optimizer = optim.SGD(model.parameters(), lr=args.lr, momentum=0.9)
    scheduler_steplr = optim.lr_scheduler.StepLR(optimizer,
                                                 step_size=50,
                                                 gamma=0.1)
    scheduler_warmup = GradualWarmupScheduler(optimizer,
                                              multiplier=1,
                                              total_epoch=5,
                                              after_scheduler=scheduler_steplr)
    optimizer.zero_grad()
    optimizer.step()

    print("initial_learning_rate:", optimizer.defaults['lr'])
    ## Mixed precision training https://github.com/NVIDIA/apex
    if mixed_precision:
        model, optimizer = amp.initialize(model,
                                          optimizer,
                                          opt_level='O1',
                                          loss_scale=args.loss_scale)

    if used_multi_gpu:
        model = DDP(model, delay_allreduce=True)
        # model = DDP(model)

    criterion = CutMixCrossEntropyLoss(True)  ##cutmixed
    #
    # # 4. training
    writer = SummaryWriter()
    top1 = AverageMeter()
    top3 = AverageMeter()
    e = 0

    for epoch in range(1, train_epoch + 1):
        epoch_loss = 0.0
        model.train()
        scheduler_warmup.step(
            epoch
        )  ## pytorch-gradual-warmup-lr https://github.com/ildoonet/pytorch-gradual-warmup-lr
        # print(epoch, optimizer.param_groups[0]['lr'])

        for batch_idx, data in enumerate(train_loader):
            # n_iter = (epoch*len(train_loader))+batch_idx

            ### if want to save dataloader image
            # data_2 = data[0][1].cpu().numpy()
            # data_2 = data_2.transpose(1,2,0)
            # data_2 -= data_2.min()
            # data_2 /= data_2.max()
            # data_2 *= 255

            #
            # cv.imwrite("./data_aug_sample/{}.jpeg".format(batch_idx), data_2)

            # images = data[0].cuda(non_blocking=True)
            # labels = data[1].cuda(non_blocking=True)
            images = data[0]["data"]
            labels = data[0]["label"].squeeze().cuda().long()

            output = model(images)
            # loss = F.cross_entropy(output, labels)
            loss = criterion(output, labels)  ## cut mixed

            optimizer.zero_grad()

            if mixed_precision:
                with amp.scale_loss(loss, optimizer) as scaled_loss:
                    scaled_loss.backward()
            else:
                loss.backward()
            optimizer.step()
            epoch_loss += loss.item() * images.size(0)

            # if bath_idx % embedding_log == 0:
            #     out = torch.cat((output.data, torch.ones(len(output), 1, device=device)), 1)
            #     writer.add_embedding(out, metadata=labels.data, label_img=images.data, global_step=n_iter)
        if epoch % 10 == 0:  ## every 10 epoch caculate once accuracy
            model.eval()
            for iii, val_data in enumerate(val_loader):
                # val_images = val_data[0].cuda(async=True)
                # val_labels = val_data[1].cuda(async=True)
                val_images = data[0]["data"]
                val_labels = data[0]["label"].squeeze().cuda().long()
                with torch.no_grad():
                    val_output = model(val_images)
                acc1, acc2 = accuracy_multi_gpu(val_output.data,
                                                val_labels,
                                                topk=(1, 3))

                if used_multi_gpu:
                    acc1 = reduce_tensor(acc1)
                    acc2 = reduce_tensor(acc2)

                top1.update(to_python_float(acc1), val_images.size(0))
                top3.update(to_python_float(acc2), val_images.size(0))

                # out = torch.cat((val_output.data, torch.ones(len(val_output), 1, device=device)), 1)
                # writer.add_embedding(out, metadata=val_labels.data, label_img=val_images.data, global_step=(epoch*len(val_loader))+iii)

            if args.local_rank == 0:
                print('Top1 Acc: %.3f | Top3 Acc: %.3f ' %
                      (top1.avg, top3.avg))
            e = int(epoch)
            torch.save(model.state_dict(),
                       "{}/{}.pt".format(checkpoint_dir, e))
            val_loader.reset()

        torch.save(model.state_dict(), "{}/last.pt".format(checkpoint_dir))
        # if epoch % 25 == 0:
        #     scheduler.step()

        print("epoch:{}, loss:{:.6f}".format(epoch, epoch_loss))

        ## visualization
        writer.add_scalar('./tensorboard/acc', top1.avg, epoch)
        writer.add_scalar('./tensorboard/total_loss', epoch_loss, epoch)
        writer.add_scalar('./tensorboard/lr', optimizer.param_groups[0]['lr'],
                          epoch)
        train_loader.reset()
    writer.export_scalars_to_json("./all_scalars.json")
    writer.close()
        init_weights=opt.init_weights,
    )

    # Evolve hyperparameters (optional)
    if opt.evolve:
        best_fitness = results[2]  # use mAP for fitness

        # Write mutation results
        print_mutation(hyp, results)

        gen = 50  # generations to evolve
        for _ in range(gen):

            # Mutate hyperparameters
            old_hyp = hyp.copy()
            torch_utils.init_seeds(seed=int(time.time()))
            s = [.2, .2, .2, .2, .2, .3, .2, .2, .02, .3]
            for i, k in enumerate(hyp.keys()):
                x = (np.random.randn(1) * s[i] +
                     1)**1.1  # plt.hist(x.ravel(), 100)
                hyp[k] = hyp[k] * float(x)  # vary by about 30% 1sigma

            # Clip to limits
            keys = ['iou_t', 'momentum', 'weight_decay']
            limits = [(0, 0.90), (0.80, 0.95), (0, 0.01)]
            for k, v in zip(keys, limits):
                hyp[k] = np.clip(hyp[k], v[0], v[1])

            # Normalize loss components (sum to 1)
            keys = ['xy', 'wh', 'cls', 'conf']
            s = sum([v for k, v in hyp.items() if k in keys])
Exemple #15
0
def train(hyp, opt, device, tb_writer=None):
    logger.info(f"Hyperparameters {hyp}")
    log_dir = (
        Path(tb_writer.log_dir) if tb_writer else Path(opt.logdir) / "evolve"
    )  # logging directory
    wdir = log_dir / "weights"  # weights directory
    os.makedirs(wdir, exist_ok=True)
    last = wdir / "last.pt"
    best = wdir / "best.pt"
    results_file = str(log_dir / "results.txt")
    epochs, batch_size, total_batch_size, weights, rank = (
        opt.epochs,
        opt.batch_size,
        opt.total_batch_size,
        opt.weights,
        opt.global_rank,
    )

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

    # Configure
    cuda = device.type != "cpu"
    init_seeds(2 + rank)
    with open(opt.data) as f:
        data_dict = yaml.load(f, Loader=yaml.FullLoader)  # data dict
    with torch_distributed_zero_first(rank):
        check_dataset(data_dict)  # check

    train_path = data_dict["train"]
    test_path = train_path.replace("train", "val")
    nc, names = (
        (1, ["item"]) if opt.single_cls else (int(data_dict["nc"]), data_dict["names"])
    )  # number classes, 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
        if hyp.get("anchors"):
            ckpt["model"].yaml["anchors"] = round(hyp["anchors"])  # force autoanchor
        model = Model(opt.cfg or ckpt["model"].yaml, ch=3, nc=nc).to(device)  # create
        exclude = ["anchor"] if opt.cfg or hyp.get("anchors") 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).to(device)  # create

    # Freeze
    freeze = [
        "",
    ]  # parameter names to freeze (full or partial)
    if any(freeze):
        for k, v in model.named_parameters():
            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

    pg0, pg1, pg2 = [], [], []  # optimizer parameter groups
    for k, v in model.named_parameters():
        v.requires_grad = True
        if ".bias" in k:
            pg2.append(v)  # biases
        elif ".weight" in k and ".bn" not in k:
            pg1.append(v)  # apply weight decay
        else:
            pg0.append(v)  # all else

    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
    lf = (
        lambda x: ((1 + math.cos(x * math.pi / epochs)) / 2) * (1 - hyp["lrf"])
        + hyp["lrf"]
    )  # cosine
    scheduler = lr_scheduler.LambdaLR(optimizer, lr_lambda=lf)
    # plot_lr_scheduler(optimizer, scheduler, epochs)

    # 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"]

        # Results
        if ckpt.get("training_results") is not None:
            with open(results_file, "w") as file:
                file.write(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,
            )
            shutil.copytree(
                wdir, wdir.parent / f"weights_backup_epoch{start_epoch - 1}"
            )  # save previous weights
        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 = int(max(model.stride))  # grid size (max stride)
    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()")

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

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

    # 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,
    )
    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]:
        ema.updates = start_epoch * nb // accumulate  # set EMA updates
        testloader = create_dataloader(
            test_path,
            imgsz_test,
            total_batch_size,
            gs,
            opt,
            hyp=hyp,
            augment=False,
            cache=opt.cache_images,
            rect=True,
            rank=-1,
            world_size=opt.world_size,
            workers=opt.workers,
        )[
            0
        ]  # testloader

        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))
            plot_labels(labels, save_dir=log_dir)
            if tb_writer:
                # tb_writer.add_hparams(hyp, {})  # causes duplicate https://github.com/ultralytics/yolov5/pull/384
                tb_writer.add_histogram("classes", c, 0)

            # Anchors
            if not opt.noautoanchor:
                check_anchors(dataset, model=model, thr=hyp["anchor_t"], imgsz=imgsz)

    # Model parameters
    hyp["cls"] *= nc / 80.0  # scale coco-tuned hyp['cls'] to current dataset
    model.nc = nc  # attach number of classes to model
    model.hyp = hyp  # attach hyperparameters to model
    model.gr = 1.0  # giou loss ratio (obj_loss = 1.0 or giou)
    model.class_weights = labels_to_class_weights(dataset.labels, nc).to(
        device
    )  # attach class weights
    model.names = names

    # Start training
    t0 = time.time()
    nw = max(3 * nb, 1e3)  # 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', 'mAP', 'F1', 'val GIoU', 'val Objectness', 'val Classification'
    scheduler.last_epoch = start_epoch - 1  # do not move
    scaler = amp.GradScaler(enabled=cuda)
    logger.info(
        "Image sizes %g train, %g test\nUsing %g dataloader workers\nLogging results to %s\n"
        "Starting training for %g epochs..."
        % (imgsz, imgsz_test, dataloader.num_workers, log_dir, 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
                )  # 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", "GIoU", "obj", "cls", "total", "targets", "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])  # giou loss ratio (obj_loss = 1.0 or giou)
                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, [0.1 if j == 2 else 0.0, x["initial_lr"] * lf(epoch)]
                    )
                    if "momentum" in x:
                        x["momentum"] = np.interp(ni, xi, [0.9, 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), model
                )  # loss scaled by batch_size
                if rank != -1:
                    loss *= (
                        opt.world_size
                    )  # gradient averaged between devices in DDP mode

            # 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 ni < 3:
                    f = str(log_dir / ("train_batch%g.jpg" % ni))  # filename
                    result = plot_images(
                        images=imgs, targets=targets, paths=paths, fname=f
                    )
                    if tb_writer and result is not None:
                        tb_writer.add_image(
                            f, result, dataformats="HWC", global_step=epoch
                        )
                        # tb_writer.add_graph(model, imgs)  # add model to tensorboard

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

        # 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
            if ema:
                ema.update_attr(
                    model, include=["yaml", "nc", "hyp", "gr", "names", "stride"]
                )
            final_epoch = epoch + 1 == epochs
            if not opt.notest or final_epoch:  # Calculate mAP
                if final_epoch:  # replot predictions
                    [
                        os.remove(x)
                        for x in glob.glob(str(log_dir / "test_batch*_pred.jpg"))
                        if os.path.exists(x)
                    ]
                results, maps, times = test.test(
                    opt.data,
                    batch_size=total_batch_size,
                    imgsz=imgsz_test,
                    model=ema.ema,
                    single_cls=opt.single_cls,
                    dataloader=testloader,
                    save_dir=log_dir,
                )

            # Write
            with open(results_file, "a") as f:
                f.write(
                    s + "%10.4g" * 7 % results + "\n"
                )  # P, R, mAP, F1, test_losses=(GIoU, obj, cls)
            if len(opt.name) and opt.bucket:
                os.system(
                    "gsutil cp %s gs://%s/results/results%s.txt"
                    % (results_file, opt.bucket, opt.name)
                )

            # Tensorboard
            if tb_writer:
                tags = [
                    "train/giou_loss",
                    "train/obj_loss",
                    "train/cls_loss",  # train loss
                    "metrics/precision",
                    "metrics/recall",
                    "metrics/mAP_0.5",
                    "metrics/mAP_0.5:0.95",
                    "val/giou_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):
                    tb_writer.add_scalar(tag, x, epoch)

            # Update best mAP
            fi = fitness(
                np.array(results).reshape(1, -1)
            )  # fitness_i = weighted combination of [P, R, mAP, F1]
            if fi > best_fitness:
                best_fitness = fi

            # Save model
            save = (not opt.nosave) or (final_epoch and not opt.evolve)
            if save:
                with open(results_file, "r") as f:  # create checkpoint
                    ckpt = {
                        "epoch": epoch,
                        "best_fitness": best_fitness,
                        "training_results": f.read(),
                        "model": ema.ema,
                        "optimizer": None if final_epoch else optimizer.state_dict(),
                    }

                # Save last, best and delete
                torch.save(ckpt, last)
                if best_fitness == fi:
                    torch.save(ckpt, best)
                del ckpt
        # end epoch ----------------------------------------------------------------------------------------------------
    # end training

    if rank in [-1, 0]:
        # Strip optimizers
        n = opt.name if opt.name.isnumeric() else ""
        fresults, flast, fbest = (
            log_dir / f"results{n}.txt",
            wdir / f"last{n}.pt",
            wdir / f"best{n}.pt",
        )
        for f1, f2 in zip(
            [wdir / "last.pt", wdir / "best.pt", results_file], [flast, fbest, fresults]
        ):
            if os.path.exists(f1):
                os.rename(f1, f2)  # rename
                if str(f2).endswith(".pt"):  # is *.pt
                    strip_optimizer(f2)  # strip optimizer
                    os.system(
                        "gsutil cp %s gs://%s/weights" % (f2, opt.bucket)
                    ) if opt.bucket else None  # upload
        # Finish
        if not opt.evolve:
            plot_results(save_dir=log_dir)  # save as results.png
        logger.info(
            "%g epochs completed in %.3f hours.\n"
            % (epoch - start_epoch + 1, (time.time() - t0) / 3600)
        )

    dist.destroy_process_group() if rank not in [-1, 0] else None
    torch.cuda.empty_cache()
    return results