/
loading.py
771 lines (597 loc) · 24.6 KB
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loading.py
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# Copyright (c) OpenMMLab. All rights reserved.
import warnings
from pathlib import Path
from typing import Dict, Optional, Union
import mmcv
import mmengine.fileio as fileio
import numpy as np
from mmcv.transforms import BaseTransform
from mmcv.transforms import LoadAnnotations as MMCV_LoadAnnotations
from mmcv.transforms import LoadImageFromFile
from mmseg.registry import TRANSFORMS
from mmseg.utils import datafrombytes
try:
from osgeo import gdal
except ImportError:
gdal = None
@TRANSFORMS.register_module()
class LoadAnnotations(MMCV_LoadAnnotations):
"""Load annotations for semantic segmentation provided by dataset.
The annotation format is as the following:
.. code-block:: python
{
# Filename of semantic segmentation ground truth file.
'seg_map_path': 'a/b/c'
}
After this module, the annotation has been changed to the format below:
.. code-block:: python
{
# in str
'seg_fields': List
# In uint8 type.
'gt_seg_map': np.ndarray (H, W)
}
Required Keys:
- seg_map_path (str): Path of semantic segmentation ground truth file.
Added Keys:
- seg_fields (List)
- gt_seg_map (np.uint8)
Args:
reduce_zero_label (bool, optional): Whether reduce all label value
by 1. Usually used for datasets where 0 is background label.
Defaults to None.
imdecode_backend (str): The image decoding backend type. The backend
argument for :func:``mmcv.imfrombytes``.
See :fun:``mmcv.imfrombytes`` for details.
Defaults to 'pillow'.
backend_args (dict): Arguments to instantiate a file backend.
See https://mmengine.readthedocs.io/en/latest/api/fileio.htm
for details. Defaults to None.
Notes: mmcv>=2.0.0rc4, mmengine>=0.2.0 required.
"""
def __init__(
self,
reduce_zero_label=None,
backend_args=None,
imdecode_backend='pillow',
) -> None:
super().__init__(
with_bbox=False,
with_label=False,
with_seg=True,
with_keypoints=False,
imdecode_backend=imdecode_backend,
backend_args=backend_args)
self.reduce_zero_label = reduce_zero_label
if self.reduce_zero_label is not None:
warnings.warn('`reduce_zero_label` will be deprecated, '
'if you would like to ignore the zero label, please '
'set `reduce_zero_label=True` when dataset '
'initialized')
self.imdecode_backend = imdecode_backend
def _load_seg_map(self, results: dict) -> None:
"""Private function to load semantic segmentation annotations.
Args:
results (dict): Result dict from :obj:``mmcv.BaseDataset``.
Returns:
dict: The dict contains loaded semantic segmentation annotations.
"""
img_bytes = fileio.get(
results['seg_map_path'], backend_args=self.backend_args)
gt_semantic_seg = mmcv.imfrombytes(
img_bytes, flag='unchanged',
backend=self.imdecode_backend).squeeze().astype(np.uint8)
# reduce zero_label
if self.reduce_zero_label is None:
self.reduce_zero_label = results['reduce_zero_label']
assert self.reduce_zero_label == results['reduce_zero_label'], \
'Initialize dataset with `reduce_zero_label` as ' \
f'{results["reduce_zero_label"]} but when load annotation ' \
f'the `reduce_zero_label` is {self.reduce_zero_label}'
if self.reduce_zero_label:
# avoid using underflow conversion
gt_semantic_seg[gt_semantic_seg == 0] = 255
gt_semantic_seg = gt_semantic_seg - 1
gt_semantic_seg[gt_semantic_seg == 254] = 255
# modify if custom classes
if results.get('label_map', None) is not None:
# Add deep copy to solve bug of repeatedly
# replace `gt_semantic_seg`, which is reported in
# https://github.com/open-mmlab/mmsegmentation/pull/1445/
gt_semantic_seg_copy = gt_semantic_seg.copy()
for old_id, new_id in results['label_map'].items():
gt_semantic_seg[gt_semantic_seg_copy == old_id] = new_id
results['gt_seg_map'] = gt_semantic_seg
results['seg_fields'].append('gt_seg_map')
def __repr__(self) -> str:
repr_str = self.__class__.__name__
repr_str += f'(reduce_zero_label={self.reduce_zero_label}, '
repr_str += f"imdecode_backend='{self.imdecode_backend}', "
repr_str += f'backend_args={self.backend_args})'
return repr_str
@TRANSFORMS.register_module()
class LoadImageFromNDArray(LoadImageFromFile):
"""Load an image from ``results['img']``.
Similar with :obj:`LoadImageFromFile`, but the image has been loaded as
:obj:`np.ndarray` in ``results['img']``. Can be used when loading image
from webcam.
Required Keys:
- img
Modified Keys:
- img
- img_path
- img_shape
- ori_shape
Args:
to_float32 (bool): Whether to convert the loaded image to a float32
numpy array. If set to False, the loaded image is an uint8 array.
Defaults to False.
"""
def transform(self, results: dict) -> dict:
"""Transform function to add image meta information.
Args:
results (dict): Result dict with Webcam read image in
``results['img']``.
Returns:
dict: The dict contains loaded image and meta information.
"""
img = results['img']
if self.to_float32:
img = img.astype(np.float32)
results['img_path'] = None
results['img'] = img
results['img_shape'] = img.shape[:2]
results['ori_shape'] = img.shape[:2]
return results
@TRANSFORMS.register_module()
class LoadBiomedicalImageFromFile(BaseTransform):
"""Load an biomedical mage from file.
Required Keys:
- img_path
Added Keys:
- img (np.ndarray): Biomedical image with shape (N, Z, Y, X) by default,
N is the number of modalities, and data type is float32
if set to_float32 = True, or float64 if decode_backend is 'nifti' and
to_float32 is False.
- img_shape
- ori_shape
Args:
decode_backend (str): The data decoding backend type. Options are
'numpy'and 'nifti', and there is a convention that when backend is
'nifti' the axis of data loaded is XYZ, and when backend is
'numpy', the the axis is ZYX. The data will be transposed if the
backend is 'nifti'. Defaults to 'nifti'.
to_xyz (bool): Whether transpose data from Z, Y, X to X, Y, Z.
Defaults to False.
to_float32 (bool): Whether to convert the loaded image to a float32
numpy array. If set to False, the loaded image is an float64 array.
Defaults to True.
backend_args (dict, Optional): Arguments to instantiate a file backend.
See https://mmengine.readthedocs.io/en/latest/api/fileio.htm
for details. Defaults to None.
Notes: mmcv>=2.0.0rc4, mmengine>=0.2.0 required.
"""
def __init__(self,
decode_backend: str = 'nifti',
to_xyz: bool = False,
to_float32: bool = True,
backend_args: Optional[dict] = None) -> None:
self.decode_backend = decode_backend
self.to_xyz = to_xyz
self.to_float32 = to_float32
self.backend_args = backend_args.copy() if backend_args else None
def transform(self, results: Dict) -> Dict:
"""Functions to load image.
Args:
results (dict): Result dict from :obj:``mmcv.BaseDataset``.
Returns:
dict: The dict contains loaded image and meta information.
"""
filename = results['img_path']
data_bytes = fileio.get(filename, self.backend_args)
img = datafrombytes(data_bytes, backend=self.decode_backend)
if self.to_float32:
img = img.astype(np.float32)
if len(img.shape) == 3:
img = img[None, ...]
if self.decode_backend == 'nifti':
img = img.transpose(0, 3, 2, 1)
if self.to_xyz:
img = img.transpose(0, 3, 2, 1)
results['img'] = img
results['img_shape'] = img.shape[1:]
results['ori_shape'] = img.shape[1:]
return results
def __repr__(self):
repr_str = (f'{self.__class__.__name__}('
f"decode_backend='{self.decode_backend}', "
f'to_xyz={self.to_xyz}, '
f'to_float32={self.to_float32}, '
f'backend_args={self.backend_args})')
return repr_str
@TRANSFORMS.register_module()
class LoadBiomedicalAnnotation(BaseTransform):
"""Load ``seg_map`` annotation provided by biomedical dataset.
The annotation format is as the following:
.. code-block:: python
{
'gt_seg_map': np.ndarray (X, Y, Z) or (Z, Y, X)
}
Required Keys:
- seg_map_path
Added Keys:
- gt_seg_map (np.ndarray): Biomedical seg map with shape (Z, Y, X) by
default, and data type is float32 if set to_float32 = True, or
float64 if decode_backend is 'nifti' and to_float32 is False.
Args:
decode_backend (str): The data decoding backend type. Options are
'numpy'and 'nifti', and there is a convention that when backend is
'nifti' the axis of data loaded is XYZ, and when backend is
'numpy', the the axis is ZYX. The data will be transposed if the
backend is 'nifti'. Defaults to 'nifti'.
to_xyz (bool): Whether transpose data from Z, Y, X to X, Y, Z.
Defaults to False.
to_float32 (bool): Whether to convert the loaded seg map to a float32
numpy array. If set to False, the loaded image is an float64 array.
Defaults to True.
backend_args (dict, Optional): Arguments to instantiate a file backend.
See :class:`mmengine.fileio` for details.
Defaults to None.
Notes: mmcv>=2.0.0rc4, mmengine>=0.2.0 required.
"""
def __init__(self,
decode_backend: str = 'nifti',
to_xyz: bool = False,
to_float32: bool = True,
backend_args: Optional[dict] = None) -> None:
super().__init__()
self.decode_backend = decode_backend
self.to_xyz = to_xyz
self.to_float32 = to_float32
self.backend_args = backend_args.copy() if backend_args else None
def transform(self, results: Dict) -> Dict:
"""Functions to load image.
Args:
results (dict): Result dict from :obj:``mmcv.BaseDataset``.
Returns:
dict: The dict contains loaded image and meta information.
"""
data_bytes = fileio.get(results['seg_map_path'], self.backend_args)
gt_seg_map = datafrombytes(data_bytes, backend=self.decode_backend)
if self.to_float32:
gt_seg_map = gt_seg_map.astype(np.float32)
if self.decode_backend == 'nifti':
gt_seg_map = gt_seg_map.transpose(2, 1, 0)
if self.to_xyz:
gt_seg_map = gt_seg_map.transpose(2, 1, 0)
results['gt_seg_map'] = gt_seg_map
return results
def __repr__(self):
repr_str = (f'{self.__class__.__name__}('
f"decode_backend='{self.decode_backend}', "
f'to_xyz={self.to_xyz}, '
f'to_float32={self.to_float32}, '
f'backend_args={self.backend_args})')
return repr_str
@TRANSFORMS.register_module()
class LoadBiomedicalData(BaseTransform):
"""Load an biomedical image and annotation from file.
The loading data format is as the following:
.. code-block:: python
{
'img': np.ndarray data[:-1, X, Y, Z]
'seg_map': np.ndarray data[-1, X, Y, Z]
}
Required Keys:
- img_path
Added Keys:
- img (np.ndarray): Biomedical image with shape (N, Z, Y, X) by default,
N is the number of modalities.
- gt_seg_map (np.ndarray, optional): Biomedical seg map with shape
(Z, Y, X) by default.
- img_shape
- ori_shape
Args:
with_seg (bool): Whether to parse and load the semantic segmentation
annotation. Defaults to False.
decode_backend (str): The data decoding backend type. Options are
'numpy'and 'nifti', and there is a convention that when backend is
'nifti' the axis of data loaded is XYZ, and when backend is
'numpy', the the axis is ZYX. The data will be transposed if the
backend is 'nifti'. Defaults to 'nifti'.
to_xyz (bool): Whether transpose data from Z, Y, X to X, Y, Z.
Defaults to False.
backend_args (dict, Optional): Arguments to instantiate a file backend.
See https://mmengine.readthedocs.io/en/latest/api/fileio.htm
for details. Defaults to None.
Notes: mmcv>=2.0.0rc4, mmengine>=0.2.0 required.
"""
def __init__(self,
with_seg=False,
decode_backend: str = 'numpy',
to_xyz: bool = False,
backend_args: Optional[dict] = None) -> None: # noqa
self.with_seg = with_seg
self.decode_backend = decode_backend
self.to_xyz = to_xyz
self.backend_args = backend_args.copy() if backend_args else None
def transform(self, results: Dict) -> Dict:
"""Functions to load image.
Args:
results (dict): Result dict from :obj:``mmcv.BaseDataset``.
Returns:
dict: The dict contains loaded image and meta information.
"""
data_bytes = fileio.get(results['img_path'], self.backend_args)
data = datafrombytes(data_bytes, backend=self.decode_backend)
# img is 4D data (N, X, Y, Z), N is the number of protocol
img = data[:-1, :]
if self.decode_backend == 'nifti':
img = img.transpose(0, 3, 2, 1)
if self.to_xyz:
img = img.transpose(0, 3, 2, 1)
results['img'] = img
results['img_shape'] = img.shape[1:]
results['ori_shape'] = img.shape[1:]
if self.with_seg:
gt_seg_map = data[-1, :]
if self.decode_backend == 'nifti':
gt_seg_map = gt_seg_map.transpose(2, 1, 0)
if self.to_xyz:
gt_seg_map = gt_seg_map.transpose(2, 1, 0)
results['gt_seg_map'] = gt_seg_map
return results
def __repr__(self) -> str:
repr_str = (f'{self.__class__.__name__}('
f'with_seg={self.with_seg}, '
f"decode_backend='{self.decode_backend}', "
f'to_xyz={self.to_xyz}, '
f'backend_args={self.backend_args})')
return repr_str
@TRANSFORMS.register_module()
class InferencerLoader(BaseTransform):
"""Load an image from ``results['img']``.
Similar with :obj:`LoadImageFromFile`, but the image has been loaded as
:obj:`np.ndarray` in ``results['img']``. Can be used when loading image
from webcam.
Required Keys:
- img
Modified Keys:
- img
- img_path
- img_shape
- ori_shape
Args:
to_float32 (bool): Whether to convert the loaded image to a float32
numpy array. If set to False, the loaded image is an uint8 array.
Defaults to False.
"""
def __init__(self, **kwargs) -> None:
super().__init__()
self.from_file = TRANSFORMS.build(
dict(type='LoadImageFromFile', **kwargs))
self.from_ndarray = TRANSFORMS.build(
dict(type='LoadImageFromNDArray', **kwargs))
def transform(self, single_input: Union[str, np.ndarray, dict]) -> dict:
"""Transform function to add image meta information.
Args:
results (dict): Result dict with Webcam read image in
``results['img']``.
Returns:
dict: The dict contains loaded image and meta information.
"""
if isinstance(single_input, str):
inputs = dict(img_path=single_input)
elif isinstance(single_input, np.ndarray):
inputs = dict(img=single_input)
elif isinstance(single_input, dict):
inputs = single_input
else:
raise NotImplementedError
if 'img' in inputs:
return self.from_ndarray(inputs)
return self.from_file(inputs)
@TRANSFORMS.register_module()
class LoadSingleRSImageFromFile(BaseTransform):
"""Load a Remote Sensing mage from file.
Required Keys:
- img_path
Modified Keys:
- img
- img_shape
- ori_shape
Args:
to_float32 (bool): Whether to convert the loaded image to a float32
numpy array. If set to False, the loaded image is a float64 array.
Defaults to True.
"""
def __init__(self, to_float32: bool = True):
self.to_float32 = to_float32
if gdal is None:
raise RuntimeError('gdal is not installed')
def transform(self, results: Dict) -> Dict:
"""Functions to load image.
Args:
results (dict): Result dict from :obj:``mmcv.BaseDataset``.
Returns:
dict: The dict contains loaded image and meta information.
"""
filename = results['img_path']
ds = gdal.Open(filename)
if ds is None:
raise Exception(f'Unable to open file: {filename}')
img = np.einsum('ijk->jki', ds.ReadAsArray())
if self.to_float32:
img = img.astype(np.float32)
results['img'] = img
results['img_shape'] = img.shape[:2]
results['ori_shape'] = img.shape[:2]
return results
def __repr__(self):
repr_str = (f'{self.__class__.__name__}('
f'to_float32={self.to_float32})')
return repr_str
@TRANSFORMS.register_module()
class LoadMultipleRSImageFromFile(BaseTransform):
"""Load two Remote Sensing mage from file.
Required Keys:
- img_path
- img_path2
Modified Keys:
- img
- img2
- img_shape
- ori_shape
Args:
to_float32 (bool): Whether to convert the loaded image to a float32
numpy array. If set to False, the loaded image is a float64 array.
Defaults to True.
"""
def __init__(self, to_float32: bool = True):
if gdal is None:
raise RuntimeError('gdal is not installed')
self.to_float32 = to_float32
def transform(self, results: Dict) -> Dict:
"""Functions to load image.
Args:
results (dict): Result dict from :obj:``mmcv.BaseDataset``.
Returns:
dict: The dict contains loaded image and meta information.
"""
filename = results['img_path']
filename2 = results['img_path2']
ds = gdal.Open(filename)
ds2 = gdal.Open(filename2)
if ds is None:
raise Exception(f'Unable to open file: {filename}')
if ds2 is None:
raise Exception(f'Unable to open file: {filename2}')
img = np.einsum('ijk->jki', ds.ReadAsArray())
img2 = np.einsum('ijk->jki', ds2.ReadAsArray())
if self.to_float32:
img = img.astype(np.float32)
img2 = img2.astype(np.float32)
if img.shape != img2.shape:
raise Exception(f'Image shapes do not match:'
f' {img.shape} vs {img2.shape}')
results['img'] = img
results['img2'] = img2
results['img_shape'] = img.shape[:2]
results['ori_shape'] = img.shape[:2]
return results
def __repr__(self):
repr_str = (f'{self.__class__.__name__}('
f'to_float32={self.to_float32})')
return repr_str
@TRANSFORMS.register_module()
class LoadDepthAnnotation(BaseTransform):
"""Load ``depth_map`` annotation provided by depth estimation dataset.
The annotation format is as the following:
.. code-block:: python
{
'gt_depth_map': np.ndarray [Y, X]
}
Required Keys:
- seg_depth_path
Added Keys:
- gt_depth_map (np.ndarray): Depth map with shape (Y, X) by
default, and data type is float32 if set to_float32 = True.
- depth_rescale_factor (float): The rescale factor of depth map, which
can be used to recover the original value of depth map.
Args:
decode_backend (str): The data decoding backend type. Options are
'numpy', 'nifti', and 'cv2'. Defaults to 'cv2'.
to_float32 (bool): Whether to convert the loaded depth map to a float32
numpy array. If set to False, the loaded image is an uint16 array.
Defaults to True.
depth_rescale_factor (float): Factor to rescale the depth value to
limit the range. Defaults to 1.0.
backend_args (dict, Optional): Arguments to instantiate a file backend.
See :class:`mmengine.fileio` for details.
Defaults to None.
Notes: mmcv>=2.0.0rc4, mmengine>=0.2.0 required.
"""
def __init__(self,
decode_backend: str = 'cv2',
to_float32: bool = True,
depth_rescale_factor: float = 1.0,
backend_args: Optional[dict] = None) -> None:
super().__init__()
self.decode_backend = decode_backend
self.to_float32 = to_float32
self.depth_rescale_factor = depth_rescale_factor
self.backend_args = backend_args.copy() if backend_args else None
def transform(self, results: Dict) -> Dict:
"""Functions to load depth map.
Args:
results (dict): Result dict from :obj:``mmcv.BaseDataset``.
Returns:
dict: The dict contains loaded depth map.
"""
data_bytes = fileio.get(results['depth_map_path'], self.backend_args)
gt_depth_map = datafrombytes(data_bytes, backend=self.decode_backend)
if self.to_float32:
gt_depth_map = gt_depth_map.astype(np.float32)
gt_depth_map *= self.depth_rescale_factor
results['gt_depth_map'] = gt_depth_map
results['seg_fields'].append('gt_depth_map')
results['depth_rescale_factor'] = self.depth_rescale_factor
return results
def __repr__(self):
repr_str = (f'{self.__class__.__name__}('
f"decode_backend='{self.decode_backend}', "
f'to_float32={self.to_float32}, '
f'backend_args={self.backend_args})')
return repr_str
@TRANSFORMS.register_module()
class LoadImageFromNpyFile(LoadImageFromFile):
"""Load an image from ``results['img_path']``.
Required Keys:
- img_path
Modified Keys:
- img
- img_shape
- ori_shape
Args:
to_float32 (bool): Whether to convert the loaded image to a float32
numpy array. If set to False, the loaded image is an uint8 array.
Defaults to False.
"""
def transform(self, results: dict) -> Optional[dict]:
"""Functions to load image.
Args:
results (dict): Result dict from
:class:`mmengine.dataset.BaseDataset`.
Returns:
dict: The dict contains loaded image and meta information.
"""
filename = results['img_path']
try:
if Path(filename).suffix in ['.npy', '.npz']:
img = np.load(filename)
else:
if self.file_client_args is not None:
file_client = fileio.FileClient.infer_client(
self.file_client_args, filename)
img_bytes = file_client.get(filename)
else:
img_bytes = fileio.get(
filename, backend_args=self.backend_args)
img = mmcv.imfrombytes(
img_bytes,
flag=self.color_type,
backend=self.imdecode_backend)
except Exception as e:
if self.ignore_empty:
return None
else:
raise e
# in some cases, images are not read successfully, the img would be
# `None`, refer to https://github.com/open-mmlab/mmpretrain/issues/1427
assert img is not None, f'failed to load image: {filename}'
if self.to_float32:
img = img.astype(np.float32)
results['img'] = img
results['img_shape'] = img.shape[:2]
results['ori_shape'] = img.shape[:2]
return results