add high level api

mmdet/api/__init__.py

@@ -0,0 +1,8 @@
+from .env import init_dist, get_root_logger, set_random_seed
+from .train import train_detector
+from .inference import inference_detector
+
+__all__ = [
+    'init_dist', 'get_root_logger', 'set_random_seed', 'train_detector',
+    'inference_detector'
+]

mmdet/api/env.py

@@ -0,0 +1,57 @@
+import logging
+import os
+import random
+
+import numpy as np
+import torch
+import torch.distributed as dist
+import torch.multiprocessing as mp
+from mmcv.runner import get_dist_info
+
+
+def init_dist(launcher, backend='nccl', **kwargs):
+    if mp.get_start_method(allow_none=True) is None:
+        mp.set_start_method('spawn')
+    if launcher == 'pytorch':
+        _init_dist_pytorch(backend, **kwargs)
+    elif launcher == 'mpi':
+        _init_dist_mpi(backend, **kwargs)
+    elif launcher == 'slurm':
+        _init_dist_slurm(backend, **kwargs)
+    else:
+        raise ValueError('Invalid launcher type: {}'.format(launcher))
+
+
+def _init_dist_pytorch(backend, **kwargs):
+    # TODO: use local_rank instead of rank % num_gpus
+    rank = int(os.environ['RANK'])
+    num_gpus = torch.cuda.device_count()
+    torch.cuda.set_device(rank % num_gpus)
+    dist.init_process_group(backend=backend, **kwargs)
+
+
+def _init_dist_mpi(backend, **kwargs):
+    raise NotImplementedError
+
+
+def _init_dist_slurm(backend, **kwargs):
+    raise NotImplementedError
+
+
+def set_random_seed(seed):
+    random.seed(seed)
+    np.random.seed(seed)
+    torch.manual_seed(seed)
+    torch.cuda.manual_seed_all(seed)
+
+
+def get_root_logger(log_level=logging.INFO):
+    logger = logging.getLogger()
+    if not logger.hasHandlers():
+        logging.basicConfig(
+            format='%(asctime)s - %(levelname)s - %(message)s',
+            level=log_level)
+    rank, _ = get_dist_info()
+    if rank != 0:
+        logger.setLevel('ERROR')
+    return logger

mmdet/api/inference.py

@@ -0,0 +1,54 @@
+import mmcv
+import numpy as np
+import torch
+
+from mmdet.datasets import to_tensor
+from mmdet.datasets.transforms import ImageTransform
+from mmdet.core import get_classes
+
+
+def _prepare_data(img, img_transform, cfg, device):
+    ori_shape = img.shape
+    img, img_shape, pad_shape, scale_factor = img_transform(
+        img, scale=cfg.data.test.img_scale)
+    img = to_tensor(img).to(device).unsqueeze(0)
+    img_meta = [
+        dict(
+            ori_shape=ori_shape,
+            img_shape=img_shape,
+            pad_shape=pad_shape,
+            scale_factor=scale_factor,
+            flip=False)
+    ]
+    return dict(img=[img], img_meta=[img_meta])
+
+
+def inference_detector(model, imgs, cfg, device='cuda:0'):
+
+    imgs = imgs if isinstance(imgs, list) else [imgs]
+    img_transform = ImageTransform(
+        size_divisor=cfg.data.test.size_divisor, **cfg.img_norm_cfg)
+    model = model.to(device)
+    model.eval()
+    for img in imgs:
+        img = mmcv.imread(img)
+        data = _prepare_data(img, img_transform, cfg, device)
+        with torch.no_grad():
+            result = model(return_loss=False, rescale=True, **data)
+        yield result
+
+
+def show_result(img, result, dataset='coco', score_thr=0.3):
+    class_names = get_classes(dataset)
+    labels = [
+        np.full(bbox.shape[0], i, dtype=np.int32)
+        for i, bbox in enumerate(result)
+    ]
+    labels = np.concatenate(labels)
+    bboxes = np.vstack(result)
+    mmcv.imshow_det_bboxes(
+        img.copy(),
+        bboxes,
+        labels,
+        class_names=class_names,
+        score_thr=score_thr)

mmdet/api/train.py

@@ -0,0 +1,117 @@
+from __future__ import division
+
+from collections import OrderedDict
+
+import torch
+from mmcv.runner import Runner, DistSamplerSeedHook
+from mmcv.parallel import MMDataParallel, MMDistributedDataParallel
+
+from mmdet.core import (DistOptimizerHook, CocoDistEvalRecallHook,
+                        CocoDistEvalmAPHook)
+from mmdet.datasets import build_dataloader
+from mmdet.models import RPN
+from .env import get_root_logger
+
+
+def parse_losses(losses):
+    log_vars = OrderedDict()
+    for loss_name, loss_value in losses.items():
+        if isinstance(loss_value, torch.Tensor):
+            log_vars[loss_name] = loss_value.mean()
+        elif isinstance(loss_value, list):
+            log_vars[loss_name] = sum(_loss.mean() for _loss in loss_value)
+        else:
+            raise TypeError(
+                '{} is not a tensor or list of tensors'.format(loss_name))
+
+    loss = sum(_value for _key, _value in log_vars.items() if 'loss' in _key)
+
+    log_vars['loss'] = loss
+    for name in log_vars:
+        log_vars[name] = log_vars[name].item()
+
+    return loss, log_vars
+
+
+def batch_processor(model, data, train_mode):
+    losses = model(**data)
+    loss, log_vars = parse_losses(losses)
+
+    outputs = dict(
+        loss=loss, log_vars=log_vars, num_samples=len(data['img'].data))
+
+    return outputs
+
+
+def train_detector(model,
+                   dataset,
+                   cfg,
+                   distributed=False,
+                   validate=False,
+                   logger=None):
+    if logger is None:
+        logger = get_root_logger(cfg.log_level)
+
+    # start training
+    if distributed:
+        _dist_train(model, dataset, cfg, validate=validate)
+    else:
+        _non_dist_train(model, dataset, cfg, validate=validate)
+
+
+def _dist_train(model, dataset, cfg, validate=False):
+    # prepare data loaders
+    data_loaders = [
+        build_dataloader(
+            dataset,
+            cfg.data.imgs_per_gpu,
+            cfg.data.workers_per_gpu,
+            dist=True)
+    ]
+    # put model on gpus
+    model = MMDistributedDataParallel(model.cuda())
+    # build runner
+    runner = Runner(model, batch_processor, cfg.optimizer, cfg.work_dir,
+                    cfg.log_level)
+    # register hooks
+    optimizer_config = DistOptimizerHook(**cfg.optimizer_config)
+    runner.register_training_hooks(cfg.lr_config, optimizer_config,
+                                   cfg.checkpoint_config, cfg.log_config)
+    runner.register_hook(DistSamplerSeedHook())
+    # register eval hooks
+    if validate:
+        if isinstance(model.module, RPN):
+            runner.register_hook(CocoDistEvalRecallHook(cfg.data.val))
+        elif cfg.data.val.type == 'CocoDataset':
+            runner.register_hook(CocoDistEvalmAPHook(cfg.data.val))
+
+    if cfg.resume_from:
+        runner.resume(cfg.resume_from)
+    elif cfg.load_from:
+        runner.load_checkpoint(cfg.load_from)
+    runner.run(data_loaders, cfg.workflow, cfg.total_epochs)
+
+
+def _non_dist_train(model, dataset, cfg, validate=False):
+    # prepare data loaders
+    data_loaders = [
+        build_dataloader(
+            dataset,
+            cfg.data.imgs_per_gpu,
+            cfg.data.workers_per_gpu,
+            cfg.gpus,
+            dist=False)
+    ]
+    # put model on gpus
+    model = MMDataParallel(model, device_ids=range(cfg.gpus)).cuda()
+    # build runner
+    runner = Runner(model, batch_processor, cfg.optimizer, cfg.work_dir,
+                    cfg.log_level)
+    runner.register_training_hooks(cfg.lr_config, cfg.optimizer_config,
+                                   cfg.checkpoint_config, cfg.log_config)
+
+    if cfg.resume_from:
+        runner.resume(cfg.resume_from)
+    elif cfg.load_from:
+        runner.load_checkpoint(cfg.load_from)
+    runner.run(data_loaders, cfg.workflow, cfg.total_epochs)

mmdet/core/utils/__init__.py

@@ -1,7 +1,7 @@
-from .dist_utils import init_dist, allreduce_grads, DistOptimizerHook
+from .dist_utils import allreduce_grads, DistOptimizerHook
 from .misc import tensor2imgs, unmap, multi_apply
 
 __all__ = [
-    'init_dist', 'allreduce_grads', 'DistOptimizerHook', 'tensor2imgs',
-    'unmap', 'multi_apply'
+    'allreduce_grads', 'DistOptimizerHook', 'tensor2imgs', 'unmap',
+    'multi_apply'
 ]

mmdet/core/utils/dist_utils.py

@@ -1,43 +1,11 @@
-import os
 from collections import OrderedDict
 
-import torch
-import torch.multiprocessing as mp
 import torch.distributed as dist
 from torch._utils import (_flatten_dense_tensors, _unflatten_dense_tensors,
                           _take_tensors)
 from mmcv.runner import OptimizerHook
 
 
-def init_dist(launcher, backend='nccl', **kwargs):
-    if mp.get_start_method(allow_none=True) is None:
-        mp.set_start_method('spawn')
-    if launcher == 'pytorch':
-        _init_dist_pytorch(backend, **kwargs)
-    elif launcher == 'mpi':
-        _init_dist_mpi(backend, **kwargs)
-    elif launcher == 'slurm':
-        _init_dist_slurm(backend, **kwargs)
-    else:
-        raise ValueError('Invalid launcher type: {}'.format(launcher))
-
-
-def _init_dist_pytorch(backend, **kwargs):
-    # TODO: use local_rank instead of rank % num_gpus
-    rank = int(os.environ['RANK'])
-    num_gpus = torch.cuda.device_count()
-    torch.cuda.set_device(rank % num_gpus)
-    dist.init_process_group(backend=backend, **kwargs)
-
-
-def _init_dist_mpi(backend, **kwargs):
-    raise NotImplementedError
-
-
-def _init_dist_slurm(backend, **kwargs):
-    raise NotImplementedError
-
-
 def _allreduce_coalesced(tensors, world_size, bucket_size_mb=-1):
     if bucket_size_mb > 0:
         bucket_size_bytes = bucket_size_mb * 1024 * 1024

mmdet/datasets/loader/build_loader.py

@@ -15,7 +15,7 @@
 def build_dataloader(dataset,
                      imgs_per_gpu,
                      workers_per_gpu,
-                     num_gpus,
+                     num_gpus=1,
                      dist=True,
                      **kwargs):
     if dist: