File size: 8,373 Bytes
98405c9 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 | # Copyright (c) Facebook, Inc. and its affiliates.
import itertools
import json
import logging
import os
from collections import OrderedDict
import pycocotools.mask as mask_util
import torch
from detectron2.data import DatasetCatalog, MetadataCatalog
from detectron2.utils.comm import all_gather, is_main_process
from detectron2.utils.file_io import PathManager
from detectron2.evaluation.evaluator import DatasetEvaluator
from typing import Optional, Union
from PIL import Image
import scipy.io
import numpy as np
def load_semseg(filename, loader_type):
if loader_type == 'PIL':
semseg = np.array(Image.open(filename), dtype=np.int64)
elif loader_type == 'MAT':
semseg = scipy.io.loadmat(filename)['LabelMap']
return semseg
def load_image_into_numpy_array(
filename: str,
dtype: Optional[Union[np.dtype, str]] = None,
) -> np.ndarray:
with PathManager.open(filename, "rb") as f:
array = np.asarray(Image.open(f), dtype=dtype)
return array
class SemSegEvaluator(DatasetEvaluator):
"""
Evaluate semantic segmentation metrics.
"""
def __init__(
self,
dataset_name,
distributed=True,
output_dir=None,
*,
num_classes=None,
ignore_label=None,
):
"""
Args:
dataset_name (str): name of the dataset to be evaluated.
distributed (bool): if True, will collect results from all ranks for evaluation.
Otherwise, will evaluate the results in the current process.
output_dir (str): an output directory to dump results.
num_classes, ignore_label: deprecated argument
"""
self._logger = logging.getLogger(__name__)
if num_classes is not None:
self._logger.warn(
"SemSegEvaluator(num_classes) is deprecated! It should be obtained from metadata."
)
if ignore_label is not None:
self._logger.warn(
"SemSegEvaluator(ignore_label) is deprecated! It should be obtained from metadata."
)
self._dataset_name = dataset_name
self._distributed = distributed
self._output_dir = output_dir
self._cpu_device = torch.device("cpu")
self.input_file_to_gt_file = {
dataset_record["file_name"]: dataset_record["sem_seg_file_name"]
for dataset_record in DatasetCatalog.get(dataset_name)
}
meta = MetadataCatalog.get(dataset_name)
# Dict that maps contiguous training ids to COCO category ids
try:
c2d = meta.stuff_dataset_id_to_contiguous_id
self._contiguous_id_to_dataset_id = {v: k for k, v in c2d.items()}
except AttributeError:
self._contiguous_id_to_dataset_id = None
self._class_names = meta.stuff_classes
self._class_offset = meta.class_offset if hasattr(meta, 'class_offset') else 0
self._num_classes = len(meta.stuff_classes)
self._semseg_loader = meta.semseg_loader if hasattr(meta, 'semseg_loader') else 'PIL'
if num_classes is not None:
assert self._num_classes == num_classes, f"{self._num_classes} != {num_classes}"
self._ignore_label = ignore_label if ignore_label is not None else meta.ignore_label
def reset(self):
self._conf_matrix = np.zeros((self._num_classes + 1, self._num_classes + 1), dtype=np.int64)
self._predictions = []
def process(self, inputs, outputs):
"""
Args:
inputs: the inputs to a model.
It is a list of dicts. Each dict corresponds to an image and
contains keys like "height", "width", "file_name".
outputs: the outputs of a model. It is either list of semantic segmentation predictions
(Tensor [H, W]) or list of dicts with key "sem_seg" that contains semantic
segmentation prediction in the same format.
"""
for input, output in zip(inputs, outputs):
output = output["sem_seg"].argmax(dim=0).to(self._cpu_device)
pred = np.array(output, dtype=np.int64)
with PathManager.open(self.input_file_to_gt_file[input["file_name"]], "rb") as f:
gt = load_semseg(f, self._semseg_loader) - self._class_offset
if isinstance(self._ignore_label, int):
ignore_label = self._ignore_label - self._class_offset
gt[gt == self._ignore_label] = self._num_classes
elif isinstance(self._ignore_label, list):
for ignore_label in self._ignore_label:
ignore_label = ignore_label - self._class_offset
gt[gt == ignore_label] = self._num_classes
self._conf_matrix += np.bincount(
(self._num_classes + 1) * pred.reshape(-1) + gt.reshape(-1),
minlength=self._conf_matrix.size,
).reshape(self._conf_matrix.shape)
self._predictions.extend(self.encode_json_sem_seg(pred, input["file_name"]))
def evaluate(self):
"""
Evaluates standard semantic segmentation metrics (http://cocodataset.org/#stuff-eval):
* Mean intersection-over-union averaged across classes (mIoU)
* Frequency Weighted IoU (fwIoU)
* Mean pixel accuracy averaged across classes (mACC)
* Pixel Accuracy (pACC)
"""
self._distributed = False
if self._output_dir:
PathManager.mkdirs(self._output_dir)
file_path = os.path.join(self._output_dir, "sem_seg_predictions.json")
with PathManager.open(file_path, "w") as f:
f.write(json.dumps(self._predictions))
acc = np.full(self._num_classes, np.nan, dtype=np.float64)
iou = np.full(self._num_classes, np.nan, dtype=np.float64)
tp = self._conf_matrix.diagonal()[:-1].astype(np.float64)
pos_gt = np.sum(self._conf_matrix[:-1, :-1], axis=0).astype(np.float64)
class_weights = pos_gt / np.sum(pos_gt)
pos_pred = np.sum(self._conf_matrix[:-1, :-1], axis=1).astype(np.float64)
acc_valid = pos_gt > 0
acc[acc_valid] = tp[acc_valid] / pos_gt[acc_valid]
iou_valid = (pos_gt + pos_pred) > 0
union = pos_gt + pos_pred - tp
iou[acc_valid] = tp[acc_valid] / union[acc_valid]
macc = np.sum(acc[acc_valid]) / np.sum(acc_valid)
miou = np.sum(iou[acc_valid]) / np.sum(iou_valid)
fiou = np.sum(iou[acc_valid] * class_weights[acc_valid])
pacc = np.sum(tp) / np.sum(pos_gt)
res = {}
res["mIoU"] = 100 * miou
res["fwIoU"] = 100 * fiou
for i, name in enumerate(self._class_names):
res["IoU-{}".format(name)] = 100 * iou[i]
res["mACC"] = 100 * macc
res["pACC"] = 100 * pacc
for i, name in enumerate(self._class_names):
res["ACC-{}".format(name)] = 100 * acc[i]
if self._output_dir:
file_path = os.path.join(self._output_dir, "sem_seg_evaluation.pth")
with PathManager.open(file_path, "wb") as f:
torch.save(res, f)
results = OrderedDict({"sem_seg": res})
self._logger.info(results)
return results
def encode_json_sem_seg(self, sem_seg, input_file_name):
"""
Convert semantic segmentation to COCO stuff format with segments encoded as RLEs.
See http://cocodataset.org/#format-results
"""
json_list = []
for label in np.unique(sem_seg):
if self._contiguous_id_to_dataset_id is not None:
assert (
label in self._contiguous_id_to_dataset_id
), "Label {} is not in the metadata info for {}".format(label, self._dataset_name)
dataset_id = self._contiguous_id_to_dataset_id[label]
else:
dataset_id = int(label)
mask = (sem_seg == label).astype(np.uint8)
mask_rle = mask_util.encode(np.array(mask[:, :, None], order="F"))[0]
mask_rle["counts"] = mask_rle["counts"].decode("utf-8")
json_list.append(
{"file_name": input_file_name, "category_id": dataset_id, "segmentation": mask_rle}
)
return json_list
|