AkashDataScience commited on
Commit
d0c450a
·
1 Parent(s): 99e2d9c
Files changed (2) hide show
  1. utils/downloads.py +103 -0
  2. utils/metrics.py +397 -0
utils/downloads.py ADDED
@@ -0,0 +1,103 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ import logging
2
+ import os
3
+ import subprocess
4
+ import urllib
5
+ from pathlib import Path
6
+
7
+ import requests
8
+ import torch
9
+
10
+
11
+ def is_url(url, check=True):
12
+ # Check if string is URL and check if URL exists
13
+ try:
14
+ url = str(url)
15
+ result = urllib.parse.urlparse(url)
16
+ assert all([result.scheme, result.netloc]) # check if is url
17
+ return (urllib.request.urlopen(url).getcode() == 200) if check else True # check if exists online
18
+ except (AssertionError, urllib.request.HTTPError):
19
+ return False
20
+
21
+
22
+ def gsutil_getsize(url=''):
23
+ # gs://bucket/file size https://cloud.google.com/storage/docs/gsutil/commands/du
24
+ s = subprocess.check_output(f'gsutil du {url}', shell=True).decode('utf-8')
25
+ return eval(s.split(' ')[0]) if len(s) else 0 # bytes
26
+
27
+
28
+ def url_getsize(url='https://ultralytics.com/images/bus.jpg'):
29
+ # Return downloadable file size in bytes
30
+ response = requests.head(url, allow_redirects=True)
31
+ return int(response.headers.get('content-length', -1))
32
+
33
+
34
+ def safe_download(file, url, url2=None, min_bytes=1E0, error_msg=''):
35
+ # Attempts to download file from url or url2, checks and removes incomplete downloads < min_bytes
36
+ from utils.general import LOGGER
37
+
38
+ file = Path(file)
39
+ assert_msg = f"Downloaded file '{file}' does not exist or size is < min_bytes={min_bytes}"
40
+ try: # url1
41
+ LOGGER.info(f'Downloading {url} to {file}...')
42
+ torch.hub.download_url_to_file(url, str(file), progress=LOGGER.level <= logging.INFO)
43
+ assert file.exists() and file.stat().st_size > min_bytes, assert_msg # check
44
+ except Exception as e: # url2
45
+ if file.exists():
46
+ file.unlink() # remove partial downloads
47
+ LOGGER.info(f'ERROR: {e}\nRe-attempting {url2 or url} to {file}...')
48
+ os.system(f"curl -# -L '{url2 or url}' -o '{file}' --retry 3 -C -") # curl download, retry and resume on fail
49
+ finally:
50
+ if not file.exists() or file.stat().st_size < min_bytes: # check
51
+ if file.exists():
52
+ file.unlink() # remove partial downloads
53
+ LOGGER.info(f"ERROR: {assert_msg}\n{error_msg}")
54
+ LOGGER.info('')
55
+
56
+
57
+ def attempt_download(file, repo='ultralytics/yolov5', release='v7.0'):
58
+ # Attempt file download from GitHub release assets if not found locally. release = 'latest', 'v7.0', etc.
59
+ from utils.general import LOGGER
60
+
61
+ def github_assets(repository, version='latest'):
62
+ # Return GitHub repo tag (i.e. 'v7.0') and assets (i.e. ['yolov5s.pt', 'yolov5m.pt', ...])
63
+ if version != 'latest':
64
+ version = f'tags/{version}' # i.e. tags/v7.0
65
+ response = requests.get(f'https://api.github.com/repos/{repository}/releases/{version}').json() # github api
66
+ return response['tag_name'], [x['name'] for x in response['assets']] # tag, assets
67
+
68
+ file = Path(str(file).strip().replace("'", ''))
69
+ if not file.exists():
70
+ # URL specified
71
+ name = Path(urllib.parse.unquote(str(file))).name # decode '%2F' to '/' etc.
72
+ if str(file).startswith(('http:/', 'https:/')): # download
73
+ url = str(file).replace(':/', '://') # Pathlib turns :// -> :/
74
+ file = name.split('?')[0] # parse authentication https://url.com/file.txt?auth...
75
+ if Path(file).is_file():
76
+ LOGGER.info(f'Found {url} locally at {file}') # file already exists
77
+ else:
78
+ safe_download(file=file, url=url, min_bytes=1E5)
79
+ return file
80
+
81
+ # GitHub assets
82
+ assets = [f'yolov5{size}{suffix}.pt' for size in 'nsmlx' for suffix in ('', '6', '-cls', '-seg')] # default
83
+ try:
84
+ tag, assets = github_assets(repo, release)
85
+ except Exception:
86
+ try:
87
+ tag, assets = github_assets(repo) # latest release
88
+ except Exception:
89
+ try:
90
+ tag = subprocess.check_output('git tag', shell=True, stderr=subprocess.STDOUT).decode().split()[-1]
91
+ except Exception:
92
+ tag = release
93
+
94
+ file.parent.mkdir(parents=True, exist_ok=True) # make parent dir (if required)
95
+ if name in assets:
96
+ url3 = 'https://drive.google.com/drive/folders/1EFQTEUeXWSFww0luse2jB9M1QNZQGwNl' # backup gdrive mirror
97
+ safe_download(
98
+ file,
99
+ url=f'https://github.com/{repo}/releases/download/{tag}/{name}',
100
+ min_bytes=1E5,
101
+ error_msg=f'{file} missing, try downloading from https://github.com/{repo}/releases/{tag} or {url3}')
102
+
103
+ return str(file)
utils/metrics.py ADDED
@@ -0,0 +1,397 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ import math
2
+ import warnings
3
+ from pathlib import Path
4
+
5
+ import matplotlib.pyplot as plt
6
+ import numpy as np
7
+ import torch
8
+
9
+ from utils import TryExcept, threaded
10
+
11
+
12
+ def fitness(x):
13
+ # Model fitness as a weighted combination of metrics
14
+ w = [0.0, 0.0, 0.1, 0.9] # weights for [P, R, [email protected], [email protected]:0.95]
15
+ return (x[:, :4] * w).sum(1)
16
+
17
+
18
+ def smooth(y, f=0.05):
19
+ # Box filter of fraction f
20
+ nf = round(len(y) * f * 2) // 2 + 1 # number of filter elements (must be odd)
21
+ p = np.ones(nf // 2) # ones padding
22
+ yp = np.concatenate((p * y[0], y, p * y[-1]), 0) # y padded
23
+ return np.convolve(yp, np.ones(nf) / nf, mode='valid') # y-smoothed
24
+
25
+
26
+ def ap_per_class(tp, conf, pred_cls, target_cls, plot=False, save_dir='.', names=(), eps=1e-16, prefix=""):
27
+ """ Compute the average precision, given the recall and precision curves.
28
+ Source: https://github.com/rafaelpadilla/Object-Detection-Metrics.
29
+ # Arguments
30
+ tp: True positives (nparray, nx1 or nx10).
31
+ conf: Objectness value from 0-1 (nparray).
32
+ pred_cls: Predicted object classes (nparray).
33
+ target_cls: True object classes (nparray).
34
+ plot: Plot precision-recall curve at [email protected]
35
+ save_dir: Plot save directory
36
+ # Returns
37
+ The average precision as computed in py-faster-rcnn.
38
+ """
39
+
40
+ # Sort by objectness
41
+ i = np.argsort(-conf)
42
+ tp, conf, pred_cls = tp[i], conf[i], pred_cls[i]
43
+
44
+ # Find unique classes
45
+ unique_classes, nt = np.unique(target_cls, return_counts=True)
46
+ nc = unique_classes.shape[0] # number of classes, number of detections
47
+
48
+ # Create Precision-Recall curve and compute AP for each class
49
+ px, py = np.linspace(0, 1, 1000), [] # for plotting
50
+ ap, p, r = np.zeros((nc, tp.shape[1])), np.zeros((nc, 1000)), np.zeros((nc, 1000))
51
+ for ci, c in enumerate(unique_classes):
52
+ i = pred_cls == c
53
+ n_l = nt[ci] # number of labels
54
+ n_p = i.sum() # number of predictions
55
+ if n_p == 0 or n_l == 0:
56
+ continue
57
+
58
+ # Accumulate FPs and TPs
59
+ fpc = (1 - tp[i]).cumsum(0)
60
+ tpc = tp[i].cumsum(0)
61
+
62
+ # Recall
63
+ recall = tpc / (n_l + eps) # recall curve
64
+ r[ci] = np.interp(-px, -conf[i], recall[:, 0], left=0) # negative x, xp because xp decreases
65
+
66
+ # Precision
67
+ precision = tpc / (tpc + fpc) # precision curve
68
+ p[ci] = np.interp(-px, -conf[i], precision[:, 0], left=1) # p at pr_score
69
+
70
+ # AP from recall-precision curve
71
+ for j in range(tp.shape[1]):
72
+ ap[ci, j], mpre, mrec = compute_ap(recall[:, j], precision[:, j])
73
+ if plot and j == 0:
74
+ py.append(np.interp(px, mrec, mpre)) # precision at [email protected]
75
+
76
+ # Compute F1 (harmonic mean of precision and recall)
77
+ f1 = 2 * p * r / (p + r + eps)
78
+ names = [v for k, v in names.items() if k in unique_classes] # list: only classes that have data
79
+ names = dict(enumerate(names)) # to dict
80
+ if plot:
81
+ plot_pr_curve(px, py, ap, Path(save_dir) / f'{prefix}PR_curve.png', names)
82
+ plot_mc_curve(px, f1, Path(save_dir) / f'{prefix}F1_curve.png', names, ylabel='F1')
83
+ plot_mc_curve(px, p, Path(save_dir) / f'{prefix}P_curve.png', names, ylabel='Precision')
84
+ plot_mc_curve(px, r, Path(save_dir) / f'{prefix}R_curve.png', names, ylabel='Recall')
85
+
86
+ i = smooth(f1.mean(0), 0.1).argmax() # max F1 index
87
+ p, r, f1 = p[:, i], r[:, i], f1[:, i]
88
+ tp = (r * nt).round() # true positives
89
+ fp = (tp / (p + eps) - tp).round() # false positives
90
+ return tp, fp, p, r, f1, ap, unique_classes.astype(int)
91
+
92
+
93
+ def compute_ap(recall, precision):
94
+ """ Compute the average precision, given the recall and precision curves
95
+ # Arguments
96
+ recall: The recall curve (list)
97
+ precision: The precision curve (list)
98
+ # Returns
99
+ Average precision, precision curve, recall curve
100
+ """
101
+
102
+ # Append sentinel values to beginning and end
103
+ mrec = np.concatenate(([0.0], recall, [1.0]))
104
+ mpre = np.concatenate(([1.0], precision, [0.0]))
105
+
106
+ # Compute the precision envelope
107
+ mpre = np.flip(np.maximum.accumulate(np.flip(mpre)))
108
+
109
+ # Integrate area under curve
110
+ method = 'interp' # methods: 'continuous', 'interp'
111
+ if method == 'interp':
112
+ x = np.linspace(0, 1, 101) # 101-point interp (COCO)
113
+ ap = np.trapz(np.interp(x, mrec, mpre), x) # integrate
114
+ else: # 'continuous'
115
+ i = np.where(mrec[1:] != mrec[:-1])[0] # points where x axis (recall) changes
116
+ ap = np.sum((mrec[i + 1] - mrec[i]) * mpre[i + 1]) # area under curve
117
+
118
+ return ap, mpre, mrec
119
+
120
+
121
+ class ConfusionMatrix:
122
+ # Updated version of https://github.com/kaanakan/object_detection_confusion_matrix
123
+ def __init__(self, nc, conf=0.25, iou_thres=0.45):
124
+ self.matrix = np.zeros((nc + 1, nc + 1))
125
+ self.nc = nc # number of classes
126
+ self.conf = conf
127
+ self.iou_thres = iou_thres
128
+
129
+ def process_batch(self, detections, labels):
130
+ """
131
+ Return intersection-over-union (Jaccard index) of boxes.
132
+ Both sets of boxes are expected to be in (x1, y1, x2, y2) format.
133
+ Arguments:
134
+ detections (Array[N, 6]), x1, y1, x2, y2, conf, class
135
+ labels (Array[M, 5]), class, x1, y1, x2, y2
136
+ Returns:
137
+ None, updates confusion matrix accordingly
138
+ """
139
+ if detections is None:
140
+ gt_classes = labels.int()
141
+ for gc in gt_classes:
142
+ self.matrix[self.nc, gc] += 1 # background FN
143
+ return
144
+
145
+ detections = detections[detections[:, 4] > self.conf]
146
+ gt_classes = labels[:, 0].int()
147
+ detection_classes = detections[:, 5].int()
148
+ iou = box_iou(labels[:, 1:], detections[:, :4])
149
+
150
+ x = torch.where(iou > self.iou_thres)
151
+ if x[0].shape[0]:
152
+ matches = torch.cat((torch.stack(x, 1), iou[x[0], x[1]][:, None]), 1).cpu().numpy()
153
+ if x[0].shape[0] > 1:
154
+ matches = matches[matches[:, 2].argsort()[::-1]]
155
+ matches = matches[np.unique(matches[:, 1], return_index=True)[1]]
156
+ matches = matches[matches[:, 2].argsort()[::-1]]
157
+ matches = matches[np.unique(matches[:, 0], return_index=True)[1]]
158
+ else:
159
+ matches = np.zeros((0, 3))
160
+
161
+ n = matches.shape[0] > 0
162
+ m0, m1, _ = matches.transpose().astype(int)
163
+ for i, gc in enumerate(gt_classes):
164
+ j = m0 == i
165
+ if n and sum(j) == 1:
166
+ self.matrix[detection_classes[m1[j]], gc] += 1 # correct
167
+ else:
168
+ self.matrix[self.nc, gc] += 1 # true background
169
+
170
+ if n:
171
+ for i, dc in enumerate(detection_classes):
172
+ if not any(m1 == i):
173
+ self.matrix[dc, self.nc] += 1 # predicted background
174
+
175
+ def matrix(self):
176
+ return self.matrix
177
+
178
+ def tp_fp(self):
179
+ tp = self.matrix.diagonal() # true positives
180
+ fp = self.matrix.sum(1) - tp # false positives
181
+ # fn = self.matrix.sum(0) - tp # false negatives (missed detections)
182
+ return tp[:-1], fp[:-1] # remove background class
183
+
184
+ @TryExcept('WARNING ⚠️ ConfusionMatrix plot failure')
185
+ def plot(self, normalize=True, save_dir='', names=()):
186
+ import seaborn as sn
187
+
188
+ array = self.matrix / ((self.matrix.sum(0).reshape(1, -1) + 1E-9) if normalize else 1) # normalize columns
189
+ array[array < 0.005] = np.nan # don't annotate (would appear as 0.00)
190
+
191
+ fig, ax = plt.subplots(1, 1, figsize=(12, 9), tight_layout=True)
192
+ nc, nn = self.nc, len(names) # number of classes, names
193
+ sn.set(font_scale=1.0 if nc < 50 else 0.8) # for label size
194
+ labels = (0 < nn < 99) and (nn == nc) # apply names to ticklabels
195
+ ticklabels = (names + ['background']) if labels else "auto"
196
+ with warnings.catch_warnings():
197
+ warnings.simplefilter('ignore') # suppress empty matrix RuntimeWarning: All-NaN slice encountered
198
+ sn.heatmap(array,
199
+ ax=ax,
200
+ annot=nc < 30,
201
+ annot_kws={
202
+ "size": 8},
203
+ cmap='Blues',
204
+ fmt='.2f',
205
+ square=True,
206
+ vmin=0.0,
207
+ xticklabels=ticklabels,
208
+ yticklabels=ticklabels).set_facecolor((1, 1, 1))
209
+ ax.set_ylabel('True')
210
+ ax.set_ylabel('Predicted')
211
+ ax.set_title('Confusion Matrix')
212
+ fig.savefig(Path(save_dir) / 'confusion_matrix.png', dpi=250)
213
+ plt.close(fig)
214
+
215
+ def print(self):
216
+ for i in range(self.nc + 1):
217
+ print(' '.join(map(str, self.matrix[i])))
218
+
219
+
220
+ class WIoU_Scale:
221
+ ''' monotonous: {
222
+ None: origin v1
223
+ True: monotonic FM v2
224
+ False: non-monotonic FM v3
225
+ }
226
+ momentum: The momentum of running mean'''
227
+
228
+ iou_mean = 1.
229
+ monotonous = False
230
+ _momentum = 1 - 0.5 ** (1 / 7000)
231
+ _is_train = True
232
+
233
+ def __init__(self, iou):
234
+ self.iou = iou
235
+ self._update(self)
236
+
237
+ @classmethod
238
+ def _update(cls, self):
239
+ if cls._is_train: cls.iou_mean = (1 - cls._momentum) * cls.iou_mean + \
240
+ cls._momentum * self.iou.detach().mean().item()
241
+
242
+ @classmethod
243
+ def _scaled_loss(cls, self, gamma=1.9, delta=3):
244
+ if isinstance(self.monotonous, bool):
245
+ if self.monotonous:
246
+ return (self.iou.detach() / self.iou_mean).sqrt()
247
+ else:
248
+ beta = self.iou.detach() / self.iou_mean
249
+ alpha = delta * torch.pow(gamma, beta - delta)
250
+ return beta / alpha
251
+ return 1
252
+
253
+
254
+ def bbox_iou(box1, box2, xywh=True, GIoU=False, DIoU=False, CIoU=False, MDPIoU=False, feat_h=640, feat_w=640, eps=1e-7):
255
+ # Returns Intersection over Union (IoU) of box1(1,4) to box2(n,4)
256
+
257
+ # Get the coordinates of bounding boxes
258
+ if xywh: # transform from xywh to xyxy
259
+ (x1, y1, w1, h1), (x2, y2, w2, h2) = box1.chunk(4, -1), box2.chunk(4, -1)
260
+ w1_, h1_, w2_, h2_ = w1 / 2, h1 / 2, w2 / 2, h2 / 2
261
+ b1_x1, b1_x2, b1_y1, b1_y2 = x1 - w1_, x1 + w1_, y1 - h1_, y1 + h1_
262
+ b2_x1, b2_x2, b2_y1, b2_y2 = x2 - w2_, x2 + w2_, y2 - h2_, y2 + h2_
263
+ else: # x1, y1, x2, y2 = box1
264
+ b1_x1, b1_y1, b1_x2, b1_y2 = box1.chunk(4, -1)
265
+ b2_x1, b2_y1, b2_x2, b2_y2 = box2.chunk(4, -1)
266
+ w1, h1 = b1_x2 - b1_x1, b1_y2 - b1_y1 + eps
267
+ w2, h2 = b2_x2 - b2_x1, b2_y2 - b2_y1 + eps
268
+
269
+ # Intersection area
270
+ inter = (torch.min(b1_x2, b2_x2) - torch.max(b1_x1, b2_x1)).clamp(0) * \
271
+ (torch.min(b1_y2, b2_y2) - torch.max(b1_y1, b2_y1)).clamp(0)
272
+
273
+ # Union Area
274
+ union = w1 * h1 + w2 * h2 - inter + eps
275
+
276
+ # IoU
277
+ iou = inter / union
278
+ if CIoU or DIoU or GIoU:
279
+ cw = torch.max(b1_x2, b2_x2) - torch.min(b1_x1, b2_x1) # convex (smallest enclosing box) width
280
+ ch = torch.max(b1_y2, b2_y2) - torch.min(b1_y1, b2_y1) # convex height
281
+ if CIoU or DIoU: # Distance or Complete IoU https://arxiv.org/abs/1911.08287v1
282
+ c2 = cw ** 2 + ch ** 2 + eps # convex diagonal squared
283
+ rho2 = ((b2_x1 + b2_x2 - b1_x1 - b1_x2) ** 2 + (b2_y1 + b2_y2 - b1_y1 - b1_y2) ** 2) / 4 # center dist ** 2
284
+ if CIoU: # https://github.com/Zzh-tju/DIoU-SSD-pytorch/blob/master/utils/box/box_utils.py#L47
285
+ v = (4 / math.pi ** 2) * torch.pow(torch.atan(w2 / h2) - torch.atan(w1 / h1), 2)
286
+ with torch.no_grad():
287
+ alpha = v / (v - iou + (1 + eps))
288
+ return iou - (rho2 / c2 + v * alpha) # CIoU
289
+ return iou - rho2 / c2 # DIoU
290
+ c_area = cw * ch + eps # convex area
291
+ return iou - (c_area - union) / c_area # GIoU https://arxiv.org/pdf/1902.09630.pdf
292
+ elif MDPIoU:
293
+ d1 = (b2_x1 - b1_x1) ** 2 + (b2_y1 - b1_y1) ** 2
294
+ d2 = (b2_x2 - b1_x2) ** 2 + (b2_y2 - b1_y2) ** 2
295
+ mpdiou_hw_pow = feat_h ** 2 + feat_w ** 2
296
+ return iou - d1 / mpdiou_hw_pow - d2 / mpdiou_hw_pow # MPDIoU
297
+ return iou # IoU
298
+
299
+
300
+ def box_iou(box1, box2, eps=1e-7):
301
+ # https://github.com/pytorch/vision/blob/master/torchvision/ops/boxes.py
302
+ """
303
+ Return intersection-over-union (Jaccard index) of boxes.
304
+ Both sets of boxes are expected to be in (x1, y1, x2, y2) format.
305
+ Arguments:
306
+ box1 (Tensor[N, 4])
307
+ box2 (Tensor[M, 4])
308
+ Returns:
309
+ iou (Tensor[N, M]): the NxM matrix containing the pairwise
310
+ IoU values for every element in boxes1 and boxes2
311
+ """
312
+
313
+ # inter(N,M) = (rb(N,M,2) - lt(N,M,2)).clamp(0).prod(2)
314
+ (a1, a2), (b1, b2) = box1.unsqueeze(1).chunk(2, 2), box2.unsqueeze(0).chunk(2, 2)
315
+ inter = (torch.min(a2, b2) - torch.max(a1, b1)).clamp(0).prod(2)
316
+
317
+ # IoU = inter / (area1 + area2 - inter)
318
+ return inter / ((a2 - a1).prod(2) + (b2 - b1).prod(2) - inter + eps)
319
+
320
+
321
+ def bbox_ioa(box1, box2, eps=1e-7):
322
+ """Returns the intersection over box2 area given box1, box2. Boxes are x1y1x2y2
323
+ box1: np.array of shape(nx4)
324
+ box2: np.array of shape(mx4)
325
+ returns: np.array of shape(nxm)
326
+ """
327
+
328
+ # Get the coordinates of bounding boxes
329
+ b1_x1, b1_y1, b1_x2, b1_y2 = box1.T
330
+ b2_x1, b2_y1, b2_x2, b2_y2 = box2.T
331
+
332
+ # Intersection area
333
+ inter_area = (np.minimum(b1_x2[:, None], b2_x2) - np.maximum(b1_x1[:, None], b2_x1)).clip(0) * \
334
+ (np.minimum(b1_y2[:, None], b2_y2) - np.maximum(b1_y1[:, None], b2_y1)).clip(0)
335
+
336
+ # box2 area
337
+ box2_area = (b2_x2 - b2_x1) * (b2_y2 - b2_y1) + eps
338
+
339
+ # Intersection over box2 area
340
+ return inter_area / box2_area
341
+
342
+
343
+ def wh_iou(wh1, wh2, eps=1e-7):
344
+ # Returns the nxm IoU matrix. wh1 is nx2, wh2 is mx2
345
+ wh1 = wh1[:, None] # [N,1,2]
346
+ wh2 = wh2[None] # [1,M,2]
347
+ inter = torch.min(wh1, wh2).prod(2) # [N,M]
348
+ return inter / (wh1.prod(2) + wh2.prod(2) - inter + eps) # iou = inter / (area1 + area2 - inter)
349
+
350
+
351
+ # Plots ----------------------------------------------------------------------------------------------------------------
352
+
353
+
354
+ @threaded
355
+ def plot_pr_curve(px, py, ap, save_dir=Path('pr_curve.png'), names=()):
356
+ # Precision-recall curve
357
+ fig, ax = plt.subplots(1, 1, figsize=(9, 6), tight_layout=True)
358
+ py = np.stack(py, axis=1)
359
+
360
+ if 0 < len(names) < 21: # display per-class legend if < 21 classes
361
+ for i, y in enumerate(py.T):
362
+ ax.plot(px, y, linewidth=1, label=f'{names[i]} {ap[i, 0]:.3f}') # plot(recall, precision)
363
+ else:
364
+ ax.plot(px, py, linewidth=1, color='grey') # plot(recall, precision)
365
+
366
+ ax.plot(px, py.mean(1), linewidth=3, color='blue', label='all classes %.3f [email protected]' % ap[:, 0].mean())
367
+ ax.set_xlabel('Recall')
368
+ ax.set_ylabel('Precision')
369
+ ax.set_xlim(0, 1)
370
+ ax.set_ylim(0, 1)
371
+ ax.legend(bbox_to_anchor=(1.04, 1), loc="upper left")
372
+ ax.set_title('Precision-Recall Curve')
373
+ fig.savefig(save_dir, dpi=250)
374
+ plt.close(fig)
375
+
376
+
377
+ @threaded
378
+ def plot_mc_curve(px, py, save_dir=Path('mc_curve.png'), names=(), xlabel='Confidence', ylabel='Metric'):
379
+ # Metric-confidence curve
380
+ fig, ax = plt.subplots(1, 1, figsize=(9, 6), tight_layout=True)
381
+
382
+ if 0 < len(names) < 21: # display per-class legend if < 21 classes
383
+ for i, y in enumerate(py):
384
+ ax.plot(px, y, linewidth=1, label=f'{names[i]}') # plot(confidence, metric)
385
+ else:
386
+ ax.plot(px, py.T, linewidth=1, color='grey') # plot(confidence, metric)
387
+
388
+ y = smooth(py.mean(0), 0.05)
389
+ ax.plot(px, y, linewidth=3, color='blue', label=f'all classes {y.max():.2f} at {px[y.argmax()]:.3f}')
390
+ ax.set_xlabel(xlabel)
391
+ ax.set_ylabel(ylabel)
392
+ ax.set_xlim(0, 1)
393
+ ax.set_ylim(0, 1)
394
+ ax.legend(bbox_to_anchor=(1.04, 1), loc="upper left")
395
+ ax.set_title(f'{ylabel}-Confidence Curve')
396
+ fig.savefig(save_dir, dpi=250)
397
+ plt.close(fig)