--- a
+++ b/tools/deploy_test.py
@@ -0,0 +1,326 @@
+# Copyright (c) OpenMMLab. All rights reserved.
+import argparse
+import os
+import os.path as osp
+import shutil
+import warnings
+from typing import Any, Iterable
+
+import mmcv
+import numpy as np
+import torch
+from mmcv.parallel import MMDataParallel
+from mmcv.runner import get_dist_info
+from mmcv.utils import DictAction
+
+from mmseg.apis import single_gpu_test
+from mmseg.datasets import build_dataloader, build_dataset
+from mmseg.models.segmentors.base import BaseSegmentor
+from mmseg.ops import resize
+
+
+class ONNXRuntimeSegmentor(BaseSegmentor):
+
+    def __init__(self, onnx_file: str, cfg: Any, device_id: int):
+        super(ONNXRuntimeSegmentor, self).__init__()
+        import onnxruntime as ort
+
+        # get the custom op path
+        ort_custom_op_path = ''
+        try:
+            from mmcv.ops import get_onnxruntime_op_path
+            ort_custom_op_path = get_onnxruntime_op_path()
+        except (ImportError, ModuleNotFoundError):
+            warnings.warn('If input model has custom op from mmcv, \
+                you may have to build mmcv with ONNXRuntime from source.')
+        session_options = ort.SessionOptions()
+        # register custom op for onnxruntime
+        if osp.exists(ort_custom_op_path):
+            session_options.register_custom_ops_library(ort_custom_op_path)
+        sess = ort.InferenceSession(onnx_file, session_options)
+        providers = ['CPUExecutionProvider']
+        options = [{}]
+        is_cuda_available = ort.get_device() == 'GPU'
+        if is_cuda_available:
+            providers.insert(0, 'CUDAExecutionProvider')
+            options.insert(0, {'device_id': device_id})
+
+        sess.set_providers(providers, options)
+
+        self.sess = sess
+        self.device_id = device_id
+        self.io_binding = sess.io_binding()
+        self.output_names = [_.name for _ in sess.get_outputs()]
+        for name in self.output_names:
+            self.io_binding.bind_output(name)
+        self.cfg = cfg
+        self.test_mode = cfg.model.test_cfg.mode
+        self.is_cuda_available = is_cuda_available
+
+    def extract_feat(self, imgs):
+        raise NotImplementedError('This method is not implemented.')
+
+    def encode_decode(self, img, img_metas):
+        raise NotImplementedError('This method is not implemented.')
+
+    def forward_train(self, imgs, img_metas, **kwargs):
+        raise NotImplementedError('This method is not implemented.')
+
+    def simple_test(self, img: torch.Tensor, img_meta: Iterable,
+                    **kwargs) -> list:
+        if not self.is_cuda_available:
+            img = img.detach().cpu()
+        elif self.device_id >= 0:
+            img = img.cuda(self.device_id)
+        device_type = img.device.type
+        self.io_binding.bind_input(
+            name='input',
+            device_type=device_type,
+            device_id=self.device_id,
+            element_type=np.float32,
+            shape=img.shape,
+            buffer_ptr=img.data_ptr())
+        self.sess.run_with_iobinding(self.io_binding)
+        seg_pred = self.io_binding.copy_outputs_to_cpu()[0]
+        # whole might support dynamic reshape
+        ori_shape = img_meta[0]['ori_shape']
+        if not (ori_shape[0] == seg_pred.shape[-2]
+                and ori_shape[1] == seg_pred.shape[-1]):
+            seg_pred = torch.from_numpy(seg_pred).float()
+            seg_pred = resize(
+                seg_pred, size=tuple(ori_shape[:2]), mode='nearest')
+            seg_pred = seg_pred.long().detach().cpu().numpy()
+        seg_pred = seg_pred[0]
+        seg_pred = list(seg_pred)
+        return seg_pred
+
+    def aug_test(self, imgs, img_metas, **kwargs):
+        raise NotImplementedError('This method is not implemented.')
+
+
+class TensorRTSegmentor(BaseSegmentor):
+
+    def __init__(self, trt_file: str, cfg: Any, device_id: int):
+        super(TensorRTSegmentor, self).__init__()
+        from mmcv.tensorrt import TRTWraper, load_tensorrt_plugin
+        try:
+            load_tensorrt_plugin()
+        except (ImportError, ModuleNotFoundError):
+            warnings.warn('If input model has custom op from mmcv, \
+                you may have to build mmcv with TensorRT from source.')
+        model = TRTWraper(
+            trt_file, input_names=['input'], output_names=['output'])
+
+        self.model = model
+        self.device_id = device_id
+        self.cfg = cfg
+        self.test_mode = cfg.model.test_cfg.mode
+
+    def extract_feat(self, imgs):
+        raise NotImplementedError('This method is not implemented.')
+
+    def encode_decode(self, img, img_metas):
+        raise NotImplementedError('This method is not implemented.')
+
+    def forward_train(self, imgs, img_metas, **kwargs):
+        raise NotImplementedError('This method is not implemented.')
+
+    def simple_test(self, img: torch.Tensor, img_meta: Iterable,
+                    **kwargs) -> list:
+        with torch.cuda.device(self.device_id), torch.no_grad():
+            seg_pred = self.model({'input': img})['output']
+        seg_pred = seg_pred.detach().cpu().numpy()
+        # whole might support dynamic reshape
+        ori_shape = img_meta[0]['ori_shape']
+        if not (ori_shape[0] == seg_pred.shape[-2]
+                and ori_shape[1] == seg_pred.shape[-1]):
+            seg_pred = torch.from_numpy(seg_pred).float()
+            seg_pred = resize(
+                seg_pred, size=tuple(ori_shape[:2]), mode='nearest')
+            seg_pred = seg_pred.long().detach().cpu().numpy()
+        seg_pred = seg_pred[0]
+        seg_pred = list(seg_pred)
+        return seg_pred
+
+    def aug_test(self, imgs, img_metas, **kwargs):
+        raise NotImplementedError('This method is not implemented.')
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser(
+        description='mmseg backend test (and eval)')
+    parser.add_argument('config', help='test config file path')
+    parser.add_argument('model', help='Input model file')
+    parser.add_argument(
+        '--backend',
+        help='Backend of the model.',
+        choices=['onnxruntime', 'tensorrt'])
+    parser.add_argument('--out', help='output result file in pickle format')
+    parser.add_argument(
+        '--format-only',
+        action='store_true',
+        help='Format the output results without perform evaluation. It is'
+        'useful when you want to format the result to a specific format and '
+        'submit it to the test server')
+    parser.add_argument(
+        '--eval',
+        type=str,
+        nargs='+',
+        help='evaluation metrics, which depends on the dataset, e.g., "mIoU"'
+        ' for generic datasets, and "cityscapes" for Cityscapes')
+    parser.add_argument('--show', action='store_true', help='show results')
+    parser.add_argument(
+        '--show-dir', help='directory where painted images will be saved')
+    parser.add_argument(
+        '--options',
+        nargs='+',
+        action=DictAction,
+        help="--options is deprecated in favor of --cfg_options' and it will "
+        'not be supported in version v0.22.0. Override some settings in the '
+        'used config, the key-value pair in xxx=yyy format will be merged '
+        'into config file. If the value to be overwritten is a list, it '
+        'should be like key="[a,b]" or key=a,b It also allows nested '
+        'list/tuple values, e.g. key="[(a,b),(c,d)]" Note that the quotation '
+        'marks are necessary and that no white space is allowed.')
+    parser.add_argument(
+        '--cfg-options',
+        nargs='+',
+        action=DictAction,
+        help='override some settings in the used config, the key-value pair '
+        'in xxx=yyy format will be merged into config file. If the value to '
+        'be overwritten is a list, it should be like key="[a,b]" or key=a,b '
+        'It also allows nested list/tuple values, e.g. key="[(a,b),(c,d)]" '
+        'Note that the quotation marks are necessary and that no white space '
+        'is allowed.')
+    parser.add_argument(
+        '--eval-options',
+        nargs='+',
+        action=DictAction,
+        help='custom options for evaluation')
+    parser.add_argument(
+        '--opacity',
+        type=float,
+        default=0.5,
+        help='Opacity of painted segmentation map. In (0, 1] range.')
+    parser.add_argument('--local_rank', type=int, default=0)
+    args = parser.parse_args()
+    if 'LOCAL_RANK' not in os.environ:
+        os.environ['LOCAL_RANK'] = str(args.local_rank)
+
+    if args.options and args.cfg_options:
+        raise ValueError(
+            '--options and --cfg-options cannot be both '
+            'specified, --options is deprecated in favor of --cfg-options. '
+            '--options will not be supported in version v0.22.0.')
+    if args.options:
+        warnings.warn('--options is deprecated in favor of --cfg-options. '
+                      '--options will not be supported in version v0.22.0.')
+        args.cfg_options = args.options
+
+    return args
+
+
+def main():
+    args = parse_args()
+
+    assert args.out or args.eval or args.format_only or args.show \
+        or args.show_dir, \
+        ('Please specify at least one operation (save/eval/format/show the '
+         'results / save the results) with the argument "--out", "--eval"'
+         ', "--format-only", "--show" or "--show-dir"')
+
+    if args.eval and args.format_only:
+        raise ValueError('--eval and --format_only cannot be both specified')
+
+    if args.out is not None and not args.out.endswith(('.pkl', '.pickle')):
+        raise ValueError('The output file must be a pkl file.')
+
+    cfg = mmcv.Config.fromfile(args.config)
+    if args.cfg_options is not None:
+        cfg.merge_from_dict(args.cfg_options)
+    cfg.model.pretrained = None
+    cfg.data.test.test_mode = True
+
+    # init distributed env first, since logger depends on the dist info.
+    distributed = False
+
+    # build the dataloader
+    # TODO: support multiple images per gpu (only minor changes are needed)
+    dataset = build_dataset(cfg.data.test)
+    data_loader = build_dataloader(
+        dataset,
+        samples_per_gpu=1,
+        workers_per_gpu=cfg.data.workers_per_gpu,
+        dist=distributed,
+        shuffle=False)
+
+    # load onnx config and meta
+    cfg.model.train_cfg = None
+
+    if args.backend == 'onnxruntime':
+        model = ONNXRuntimeSegmentor(args.model, cfg=cfg, device_id=0)
+    elif args.backend == 'tensorrt':
+        model = TensorRTSegmentor(args.model, cfg=cfg, device_id=0)
+
+    model.CLASSES = dataset.CLASSES
+    model.PALETTE = dataset.PALETTE
+
+    # clean gpu memory when starting a new evaluation.
+    torch.cuda.empty_cache()
+    eval_kwargs = {} if args.eval_options is None else args.eval_options
+
+    # Deprecated
+    efficient_test = eval_kwargs.get('efficient_test', False)
+    if efficient_test:
+        warnings.warn(
+            '``efficient_test=True`` does not have effect in tools/test.py, '
+            'the evaluation and format results are CPU memory efficient by '
+            'default')
+
+    eval_on_format_results = (
+        args.eval is not None and 'cityscapes' in args.eval)
+    if eval_on_format_results:
+        assert len(args.eval) == 1, 'eval on format results is not ' \
+                                    'applicable for metrics other than ' \
+                                    'cityscapes'
+    if args.format_only or eval_on_format_results:
+        if 'imgfile_prefix' in eval_kwargs:
+            tmpdir = eval_kwargs['imgfile_prefix']
+        else:
+            tmpdir = '.format_cityscapes'
+            eval_kwargs.setdefault('imgfile_prefix', tmpdir)
+        mmcv.mkdir_or_exist(tmpdir)
+    else:
+        tmpdir = None
+
+    model = MMDataParallel(model, device_ids=[0])
+    results = single_gpu_test(
+        model,
+        data_loader,
+        args.show,
+        args.show_dir,
+        False,
+        args.opacity,
+        pre_eval=args.eval is not None and not eval_on_format_results,
+        format_only=args.format_only or eval_on_format_results,
+        format_args=eval_kwargs)
+
+    rank, _ = get_dist_info()
+    if rank == 0:
+        if args.out:
+            warnings.warn(
+                'The behavior of ``args.out`` has been changed since MMSeg '
+                'v0.16, the pickled outputs could be seg map as type of '
+                'np.array, pre-eval results or file paths for '
+                '``dataset.format_results()``.')
+            print(f'\nwriting results to {args.out}')
+            mmcv.dump(results, args.out)
+        if args.eval:
+            dataset.evaluate(results, args.eval, **eval_kwargs)
+        if tmpdir is not None and eval_on_format_results:
+            # remove tmp dir when cityscapes evaluation
+            shutil.rmtree(tmpdir)
+
+
+if __name__ == '__main__':
+    main()