# Ultralytics YOLO 🚀, AGPL-3.0 license
"""Model validation metrics."""
import math
import warnings
from pathlib import Path
import matplotlib.pyplot as plt
import numpy as np
import torch
from ultralytics.utils import LOGGER, SimpleClass, TryExcept, plt_settings
OKS_SIGMA = np.array([.26, .25, .25, .35, .35, .79, .79, .72, .72, .62, .62, 1.07, 1.07, .87, .87, .89, .89]) / 10.0
def bbox_ioa(box1, box2, iou=False, eps=1e-7):
"""
Calculate the intersection over box2 area given box1 and box2. Boxes are in x1y1x2y2 format.
Args:
box1 (np.array): A numpy array of shape (n, 4) representing n bounding boxes.
box2 (np.array): A numpy array of shape (m, 4) representing m bounding boxes.
iou (bool): Calculate the standard iou if True else return inter_area/box2_area.
eps (float, optional): A small value to avoid division by zero. Defaults to 1e-7.
Returns:
(np.array): A numpy array of shape (n, m) representing the intersection over box2 area.
"""
# Get the coordinates of bounding boxes
b1_x1, b1_y1, b1_x2, b1_y2 = box1.T
b2_x1, b2_y1, b2_x2, b2_y2 = box2.T
# Intersection area
inter_area = (np.minimum(b1_x2[:, None], b2_x2) - np.maximum(b1_x1[:, None], b2_x1)).clip(0) * \
(np.minimum(b1_y2[:, None], b2_y2) - np.maximum(b1_y1[:, None], b2_y1)).clip(0)
# Box2 area
area = (b2_x2 - b2_x1) * (b2_y2 - b2_y1)
if iou:
box1_area = (b1_x2 - b1_x1) * (b1_y2 - b1_y1)
area = area + box1_area[:, None] - inter_area
# Intersection over box2 area
return inter_area / (area + eps)
def box_iou(box1, box2, eps=1e-7):
"""
Calculate intersection-over-union (IoU) of boxes. Both sets of boxes are expected to be in (x1, y1, x2, y2) format.
Based on https://github.com/pytorch/vision/blob/master/torchvision/ops/boxes.py
Args:
box1 (torch.Tensor): A tensor of shape (N, 4) representing N bounding boxes.
box2 (torch.Tensor): A tensor of shape (M, 4) representing M bounding boxes.
eps (float, optional): A small value to avoid division by zero. Defaults to 1e-7.
Returns:
(torch.Tensor): An NxM tensor containing the pairwise IoU values for every element in box1 and box2.
"""
# inter(N,M) = (rb(N,M,2) - lt(N,M,2)).clamp(0).prod(2)
(a1, a2), (b1, b2) = box1.unsqueeze(1).chunk(2, 2), box2.unsqueeze(0).chunk(2, 2)
inter = (torch.min(a2, b2) - torch.max(a1, b1)).clamp_(0).prod(2)
# IoU = inter / (area1 + area2 - inter)
return inter / ((a2 - a1).prod(2) + (b2 - b1).prod(2) - inter + eps)
def bbox_iou(box1, box2, xywh=True, GIoU=False, DIoU=False, CIoU=False, eps=1e-7):
"""
Calculate Intersection over Union (IoU) of box1(1, 4) to box2(n, 4).
Args:
box1 (torch.Tensor): A tensor representing a single bounding box with shape (1, 4).
box2 (torch.Tensor): A tensor representing n bounding boxes with shape (n, 4).
xywh (bool, optional): If True, input boxes are in (x, y, w, h) format. If False, input boxes are in
(x1, y1, x2, y2) format. Defaults to True.
GIoU (bool, optional): If True, calculate Generalized IoU. Defaults to False.
DIoU (bool, optional): If True, calculate Distance IoU. Defaults to False.
CIoU (bool, optional): If True, calculate Complete IoU. Defaults to False.
eps (float, optional): A small value to avoid division by zero. Defaults to 1e-7.
Returns:
(torch.Tensor): IoU, GIoU, DIoU, or CIoU values depending on the specified flags.
"""
# Get the coordinates of bounding boxes
if xywh: # transform from xywh to xyxy
(x1, y1, w1, h1), (x2, y2, w2, h2) = box1.chunk(4, -1), box2.chunk(4, -1)
w1_, h1_, w2_, h2_ = w1 / 2, h1 / 2, w2 / 2, h2 / 2
b1_x1, b1_x2, b1_y1, b1_y2 = x1 - w1_, x1 + w1_, y1 - h1_, y1 + h1_
b2_x1, b2_x2, b2_y1, b2_y2 = x2 - w2_, x2 + w2_, y2 - h2_, y2 + h2_
else: # x1, y1, x2, y2 = box1
b1_x1, b1_y1, b1_x2, b1_y2 = box1.chunk(4, -1)
b2_x1, b2_y1, b2_x2, b2_y2 = box2.chunk(4, -1)
w1, h1 = b1_x2 - b1_x1, b1_y2 - b1_y1 + eps
w2, h2 = b2_x2 - b2_x1, b2_y2 - b2_y1 + eps
# Intersection area
inter = (b1_x2.minimum(b2_x2) - b1_x1.maximum(b2_x1)).clamp_(0) * \
(b1_y2.minimum(b2_y2) - b1_y1.maximum(b2_y1)).clamp_(0)
# Union Area
union = w1 * h1 + w2 * h2 - inter + eps
# IoU
iou = inter / union
if CIoU or DIoU or GIoU:
cw = b1_x2.maximum(b2_x2) - b1_x1.minimum(b2_x1) # convex (smallest enclosing box) width
ch = b1_y2.maximum(b2_y2) - b1_y1.minimum(b2_y1) # convex height
if CIoU or DIoU: # Distance or Complete IoU https://arxiv.org/abs/1911.08287v1
c2 = cw ** 2 + ch ** 2 + eps # convex diagonal squared
rho2 = ((b2_x1 + b2_x2 - b1_x1 - b1_x2) ** 2 + (b2_y1 + b2_y2 - b1_y1 - b1_y2) ** 2) / 4 # center dist ** 2
if CIoU: # https://github.com/Zzh-tju/DIoU-SSD-pytorch/blob/master/utils/box/box_utils.py#L47
v = (4 / math.pi ** 2) * (torch.atan(w2 / h2) - torch.atan(w1 / h1)).pow(2)
with torch.no_grad():
alpha = v / (v - iou + (1 + eps))
return iou - (rho2 / c2 + v * alpha) # CIoU
return iou - rho2 / c2 # DIoU
c_area = cw * ch + eps # convex area
return iou - (c_area - union) / c_area # GIoU https://arxiv.org/pdf/1902.09630.pdf
return iou # IoU
def mask_iou(mask1, mask2, eps=1e-7):
"""
Calculate masks IoU.
Args:
mask1 (torch.Tensor): A tensor of shape (N, n) where N is the number of ground truth objects and n is the
product of image width and height.
mask2 (torch.Tensor): A tensor of shape (M, n) where M is the number of predicted objects and n is the
product of image width and height.
eps (float, optional): A small value to avoid division by zero. Defaults to 1e-7.
Returns:
(torch.Tensor): A tensor of shape (N, M) representing masks IoU.
"""
intersection = torch.matmul(mask1, mask2.T).clamp_(0)
union = (mask1.sum(1)[:, None] + mask2.sum(1)[None]) - intersection # (area1 + area2) - intersection
return intersection / (union + eps)
def kpt_iou(kpt1, kpt2, area, sigma, eps=1e-7):
"""
Calculate Object Keypoint Similarity (OKS).
Args:
kpt1 (torch.Tensor): A tensor of shape (N, 17, 3) representing ground truth keypoints.
kpt2 (torch.Tensor): A tensor of shape (M, 17, 3) representing predicted keypoints.
area (torch.Tensor): A tensor of shape (N,) representing areas from ground truth.
sigma (list): A list containing 17 values representing keypoint scales.
eps (float, optional): A small value to avoid division by zero. Defaults to 1e-7.
Returns:
(torch.Tensor): A tensor of shape (N, M) representing keypoint similarities.
"""
d = (kpt1[:, None, :, 0] - kpt2[..., 0]) ** 2 + (kpt1[:, None, :, 1] - kpt2[..., 1]) ** 2 # (N, M, 17)
sigma = torch.tensor(sigma, device=kpt1.device, dtype=kpt1.dtype) # (17, )
kpt_mask = kpt1[..., 2] != 0 # (N, 17)
e = d / (2 * sigma) ** 2 / (area[:, None, None] + eps) / 2 # from cocoeval
# e = d / ((area[None, :, None] + eps) * sigma) ** 2 / 2 # from formula
return (torch.exp(-e) * kpt_mask[:, None]).sum(-1) / (kpt_mask.sum(-1)[:, None] + eps)
def smooth_BCE(eps=0.1):
"""
Computes smoothed positive and negative Binary Cross-Entropy targets.
This function calculates positive and negative label smoothing BCE targets based on a given epsilon value.
For implementation details, refer to https://github.com/ultralytics/yolov3/issues/238#issuecomment-598028441.
Args:
eps (float, optional): The epsilon value for label smoothing. Defaults to 0.1.
Returns:
(tuple): A tuple containing the positive and negative label smoothing BCE targets.
"""
return 1.0 - 0.5 * eps, 0.5 * eps
class ConfusionMatrix:
"""
A class for calculating and updating a confusion matrix for object detection and classification tasks.
Attributes:
task (str): The type of task, either 'detect' or 'classify'.
matrix (np.array): The confusion matrix, with dimensions depending on the task.
nc (int): The number of classes.
conf (float): The confidence threshold for detections.
iou_thres (float): The Intersection over Union threshold.
"""
def __init__(self, nc, conf=0.25, iou_thres=0.45, task='detect'):
"""Initialize attributes for the YOLO model."""
self.task = task
self.matrix = np.zeros((nc + 1, nc + 1)) if self.task == 'detect' else np.zeros((nc, nc))
self.nc = nc # number of classes
self.conf = 0.25 if conf in (None, 0.001) else conf # apply 0.25 if default val conf is passed
self.iou_thres = iou_thres
def process_cls_preds(self, preds, targets):
"""
Update confusion matrix for classification task.
Args:
preds (Array[N, min(nc,5)]): Predicted class labels.
targets (Array[N, 1]): Ground truth class labels.
"""
preds, targets = torch.cat(preds)[:, 0], torch.cat(targets)
for p, t in zip(preds.cpu().numpy(), targets.cpu().numpy()):
self.matrix[p][t] += 1
def process_batch(self, detections, labels):
"""
Update confusion matrix for object detection task.
Args:
detections (Array[N, 6]): Detected bounding boxes and their associated information.
Each row should contain (x1, y1, x2, y2, conf, class).
labels (Array[M, 5]): Ground truth bounding boxes and their associated class labels.
Each row should contain (class, x1, y1, x2, y2).
"""
if labels.size(0) == 0: # Check if labels is empty
if detections is not None:
detections = detections[detections[:, 4] > self.conf]
detection_classes = detections[:, 5].int()
for dc in detection_classes:
self.matrix[dc, self.nc] += 1 # false positives
return
if detections is None:
gt_classes = labels.int()
for gc in gt_classes:
self.matrix[self.nc, gc] += 1 # background FN
return
detections = detections[detections[:, 4] > self.conf]
gt_classes = labels[:, 0].int()
detection_classes = detections[:, 5].int()
iou = box_iou(labels[:, 1:], detections[:, :4])
x = torch.where(iou > self.iou_thres)
if x[0].shape[0]:
matches = torch.cat((torch.stack(x, 1), iou[x[0], x[1]][:, None]), 1).cpu().numpy()
if x[0].shape[0] > 1:
matches = matches[matches[:, 2].argsort()[::-1]]
matches = matches[np.unique(matches[:, 1], return_index=True)[1]]
matches = matches[matches[:, 2].argsort()[::-1]]
matches = matches[np.unique(matches[:, 0], return_index=True)[1]]
else:
matches = np.zeros((0, 3))
n = matches.shape[0] > 0
m0, m1, _ = matches.transpose().astype(int)
for i, gc in enumerate(gt_classes):
j = m0 == i
if n and sum(j) == 1:
self.matrix[detection_classes[m1[j]], gc] += 1 # correct
else:
self.matrix[self.nc, gc] += 1 # true background
if n:
for i, dc in enumerate(detection_classes):
if not any(m1 == i):
self.matrix[dc, self.nc] += 1 # predicted background
def matrix(self):
"""Returns the confusion matrix."""
return self.matrix
def tp_fp(self):
"""Returns true positives and false positives."""
tp = self.matrix.diagonal() # true positives
fp = self.matrix.sum(1) - tp # false positives
# fn = self.matrix.sum(0) - tp # false negatives (missed detections)
return (tp[:-1], fp[:-1]) if self.task == 'detect' else (tp, fp) # remove background class if task=detect
@TryExcept('WARNING ⚠️ ConfusionMatrix plot failure')
@plt_settings()
def plot(self, normalize=True, save_dir='', names=(), on_plot=None):
"""
Plot the confusion matrix using seaborn and save it to a file.
Args:
normalize (bool): Whether to normalize the confusion matrix.
save_dir (str): Directory where the plot will be saved.
names (tuple): Names of classes, used as labels on the plot.
on_plot (func): An optional callback to pass plots path and data when they are rendered.
"""
import seaborn as sn
array = self.matrix / ((self.matrix.sum(0).reshape(1, -1) + 1E-9) if normalize else 1) # normalize columns
array[array < 0.005] = np.nan # don't annotate (would appear as 0.00)
fig, ax = plt.subplots(1, 1, figsize=(12, 9), tight_layout=True)
nc, nn = self.nc, len(names) # number of classes, names
sn.set(font_scale=1.0 if nc < 50 else 0.8) # for label size
labels = (0 < nn < 99) and (nn == nc) # apply names to ticklabels
ticklabels = (list(names) + ['background']) if labels else 'auto'
with warnings.catch_warnings():
warnings.simplefilter('ignore') # suppress empty matrix RuntimeWarning: All-NaN slice encountered
sn.heatmap(array,
ax=ax,
annot=nc < 30,
annot_kws={
'size': 8},
cmap='Blues',
fmt='.2f' if normalize else '.0f',
square=True,
vmin=0.0,
xticklabels=ticklabels,
yticklabels=ticklabels).set_facecolor((1, 1, 1))
title = 'Confusion Matrix' + ' Normalized' * normalize
ax.set_xlabel('True')
ax.set_ylabel('Predicted')
ax.set_title(title)
plot_fname = Path(save_dir) / f'{title.lower().replace(" ", "_")}.png'
fig.savefig(plot_fname, dpi=250)
plt.close(fig)
if on_plot:
on_plot(plot_fname)
def print(self):
"""Print the confusion matrix to the console."""
for i in range(self.nc + 1):
LOGGER.info(' '.join(map(str, self.matrix[i])))
def smooth(y, f=0.05):
"""Box filter of fraction f."""
nf = round(len(y) * f * 2) // 2 + 1 # number of filter elements (must be odd)
p = np.ones(nf // 2) # ones padding
yp = np.concatenate((p * y[0], y, p * y[-1]), 0) # y padded
return np.convolve(yp, np.ones(nf) / nf, mode='valid') # y-smoothed
@plt_settings()
def plot_pr_curve(px, py, ap, save_dir=Path('pr_curve.png'), names=(), on_plot=None):
"""Plots a precision-recall curve."""
fig, ax = plt.subplots(1, 1, figsize=(9, 6), tight_layout=True)
py = np.stack(py, axis=1)
if 0 < len(names) < 21: # display per-class legend if < 21 classes
for i, y in enumerate(py.T):
ax.plot(px, y, linewidth=1, label=f'{names[i]} {ap[i, 0]:.3f}') # plot(recall, precision)
else:
ax.plot(px, py, linewidth=1, color='grey') # plot(recall, precision)
ax.plot(px, py.mean(1), linewidth=3, color='blue', label='all classes %.3f mAP@0.5' % ap[:, 0].mean())
ax.set_xlabel('Recall')
ax.set_ylabel('Precision')
ax.set_xlim(0, 1)
ax.set_ylim(0, 1)
ax.legend(bbox_to_anchor=(1.04, 1), loc='upper left')
ax.set_title('Precision-Recall Curve')
fig.savefig(save_dir, dpi=250)
plt.close(fig)
if on_plot:
on_plot(save_dir)
@plt_settings()
def plot_mc_curve(px, py, save_dir=Path('mc_curve.png'), names=(), xlabel='Confidence', ylabel='Metric', on_plot=None):
"""Plots a metric-confidence curve."""
fig, ax = plt.subplots(1, 1, figsize=(9, 6), tight_layout=True)
if 0 < len(names) < 21: # display per-class legend if < 21 classes
for i, y in enumerate(py):
ax.plot(px, y, linewidth=1, label=f'{names[i]}') # plot(confidence, metric)
else:
ax.plot(px, py.T, linewidth=1, color='grey') # plot(confidence, metric)
y = smooth(py.mean(0), 0.05)
ax.plot(px, y, linewidth=3, color='blue', label=f'all classes {y.max():.2f} at {px[y.argmax()]:.3f}')
ax.set_xlabel(xlabel)
ax.set_ylabel(ylabel)
ax.set_xlim(0, 1)
ax.set_ylim(0, 1)
ax.legend(bbox_to_anchor=(1.04, 1), loc='upper left')
ax.set_title(f'{ylabel}-Confidence Curve')
fig.savefig(save_dir, dpi=250)
plt.close(fig)
if on_plot:
on_plot(save_dir)
def compute_ap(recall, precision):
"""
Compute the average precision (AP) given the recall and precision curves.
Args:
recall (list): The recall curve.
precision (list): The precision curve.
Returns:
(float): Average precision.
(np.ndarray): Precision envelope curve.
(np.ndarray): Modified recall curve with sentinel values added at the beginning and end.
"""
# Append sentinel values to beginning and end
mrec = np.concatenate(([0.0], recall, [1.0]))
mpre = np.concatenate(([1.0], precision, [0.0]))
# Compute the precision envelope
mpre = np.flip(np.maximum.accumulate(np.flip(mpre)))
# Integrate area under curve
method = 'interp' # methods: 'continuous', 'interp'
if method == 'interp':
x = np.linspace(0, 1, 101) # 101-point interp (COCO)
ap = np.trapz(np.interp(x, mrec, mpre), x) # integrate
else: # 'continuous'
i = np.where(mrec[1:] != mrec[:-1])[0] # points where x-axis (recall) changes
ap = np.sum((mrec[i + 1] - mrec[i]) * mpre[i + 1]) # area under curve
return ap, mpre, mrec
def ap_per_class(tp,
conf,
pred_cls,
target_cls,
plot=False,
on_plot=None,
save_dir=Path(),
names=(),
eps=1e-16,
prefix=''):
"""
Computes the average precision per class for object detection evaluation.
Args:
tp (np.ndarray): Binary array indicating whether the detection is correct (True) or not (False).
conf (np.ndarray): Array of confidence scores of the detections.
pred_cls (np.ndarray): Array of predicted classes of the detections.
target_cls (np.ndarray): Array of true classes of the detections.
plot (bool, optional): Whether to plot PR curves or not. Defaults to False.
on_plot (func, optional): A callback to pass plots path and data when they are rendered. Defaults to None.
save_dir (Path, optional): Directory to save the PR curves. Defaults to an empty path.
names (tuple, optional): Tuple of class names to plot PR curves. Defaults to an empty tuple.
eps (float, optional): A small value to avoid division by zero. Defaults to 1e-16.
prefix (str, optional): A prefix string for saving the plot files. Defaults to an empty string.
Returns:
(tuple): A tuple of six arrays and one array of unique classes, where:
tp (np.ndarray): True positive counts at threshold given by max F1 metric for each class.Shape: (nc,).
fp (np.ndarray): False positive counts at threshold given by max F1 metric for each class. Shape: (nc,).
p (np.ndarray): Precision values at threshold given by max F1 metric for each class. Shape: (nc,).
r (np.ndarray): Recall values at threshold given by max F1 metric for each class. Shape: (nc,).
f1 (np.ndarray): F1-score values at threshold given by max F1 metric for each class. Shape: (nc,).
ap (np.ndarray): Average precision for each class at different IoU thresholds. Shape: (nc, 10).
unique_classes (np.ndarray): An array of unique classes that have data. Shape: (nc,).
p_curve (np.ndarray): Precision curves for each class. Shape: (nc, 1000).
r_curve (np.ndarray): Recall curves for each class. Shape: (nc, 1000).
f1_curve (np.ndarray): F1-score curves for each class. Shape: (nc, 1000).
x (np.ndarray): X-axis values for the curves. Shape: (1000,).
prec_values: Precision values at mAP@0.5 for each class. Shape: (nc, 1000).
"""
# Sort by objectness
i = np.argsort(-conf)
tp, conf, pred_cls = tp[i], conf[i], pred_cls[i]
# Find unique classes
unique_classes, nt = np.unique(target_cls, return_counts=True)
nc = unique_classes.shape[0] # number of classes, number of detections
# Create Precision-Recall curve and compute AP for each class
x, prec_values = np.linspace(0, 1, 1000), []
# Average precision, precision and recall curves
ap, p_curve, r_curve = np.zeros((nc, tp.shape[1])), np.zeros((nc, 1000)), np.zeros((nc, 1000))
for ci, c in enumerate(unique_classes):
i = pred_cls == c
n_l = nt[ci] # number of labels
n_p = i.sum() # number of predictions
if n_p == 0 or n_l == 0:
continue
# Accumulate FPs and TPs
fpc = (1 - tp[i]).cumsum(0)
tpc = tp[i].cumsum(0)
# Recall
recall = tpc / (n_l + eps) # recall curve
r_curve[ci] = np.interp(-x, -conf[i], recall[:, 0], left=0) # negative x, xp because xp decreases
# Precision
precision = tpc / (tpc + fpc) # precision curve
p_curve[ci] = np.interp(-x, -conf[i], precision[:, 0], left=1) # p at pr_score
# AP from recall-precision curve
for j in range(tp.shape[1]):
ap[ci, j], mpre, mrec = compute_ap(recall[:, j], precision[:, j])
if plot and j == 0:
prec_values.append(np.interp(x, mrec, mpre)) # precision at mAP@0.5
prec_values = np.array(prec_values) # (nc, 1000)
# Compute F1 (harmonic mean of precision and recall)
f1_curve = 2 * p_curve * r_curve / (p_curve + r_curve + eps)
names = [v for k, v in names.items() if k in unique_classes] # list: only classes that have data
names = dict(enumerate(names)) # to dict
if plot:
plot_pr_curve(x, prec_values, ap, save_dir / f'{prefix}PR_curve.png', names, on_plot=on_plot)
plot_mc_curve(x, f1_curve, save_dir / f'{prefix}F1_curve.png', names, ylabel='F1', on_plot=on_plot)
plot_mc_curve(x, p_curve, save_dir / f'{prefix}P_curve.png', names, ylabel='Precision', on_plot=on_plot)
plot_mc_curve(x, r_curve, save_dir / f'{prefix}R_curve.png', names, ylabel='Recall', on_plot=on_plot)
i = smooth(f1_curve.mean(0), 0.1).argmax() # max F1 index
p, r, f1 = p_curve[:, i], r_curve[:, i], f1_curve[:, i] # max-F1 precision, recall, F1 values
tp = (r * nt).round() # true positives
fp = (tp / (p + eps) - tp).round() # false positives
return tp, fp, p, r, f1, ap, unique_classes.astype(int), p_curve, r_curve, f1_curve, x, prec_values
class Metric(SimpleClass):
"""
Class for computing evaluation metrics for YOLOv8 model.
Attributes:
p (list): Precision for each class. Shape: (nc,).
r (list): Recall for each class. Shape: (nc,).
f1 (list): F1 score for each class. Shape: (nc,).
all_ap (list): AP scores for all classes and all IoU thresholds. Shape: (nc, 10).
ap_class_index (list): Index of class for each AP score. Shape: (nc,).
nc (int): Number of classes.
Methods:
ap50(): AP at IoU threshold of 0.5 for all classes. Returns: List of AP scores. Shape: (nc,) or [].
ap(): AP at IoU thresholds from 0.5 to 0.95 for all classes. Returns: List of AP scores. Shape: (nc,) or [].
mp(): Mean precision of all classes. Returns: Float.
mr(): Mean recall of all classes. Returns: Float.
map50(): Mean AP at IoU threshold of 0.5 for all classes. Returns: Float.
map75(): Mean AP at IoU threshold of 0.75 for all classes. Returns: Float.
map(): Mean AP at IoU thresholds from 0.5 to 0.95 for all classes. Returns: Float.
mean_results(): Mean of results, returns mp, mr, map50, map.
class_result(i): Class-aware result, returns p[i], r[i], ap50[i], ap[i].
maps(): mAP of each class. Returns: Array of mAP scores, shape: (nc,).
fitness(): Model fitness as a weighted combination of metrics. Returns: Float.
update(results): Update metric attributes with new evaluation results.
"""
def __init__(self) -> None:
"""Initializes a Metric instance for computing evaluation metrics for the YOLOv8 model."""
self.p = [] # (nc, )
self.r = [] # (nc, )
self.f1 = [] # (nc, )
self.all_ap = [] # (nc, 10)
self.ap_class_index = [] # (nc, )
self.nc = 0
@property
def ap50(self):
"""
Returns the Average Precision (AP) at an IoU threshold of 0.5 for all classes.
Returns:
(np.ndarray, list): Array of shape (nc,) with AP50 values per class, or an empty list if not available.
"""
return self.all_ap[:, 0] if len(self.all_ap) else []
@property
def ap(self):
"""
Returns the Average Precision (AP) at an IoU threshold of 0.5-0.95 for all classes.
Returns:
(np.ndarray, list): Array of shape (nc,) with AP50-95 values per class, or an empty list if not available.
"""
return self.all_ap.mean(1) if len(self.all_ap) else []
@property
def mp(self):
"""
Returns the Mean Precision of all classes.
Returns:
(float): The mean precision of all classes.
"""
return self.p.mean() if len(self.p) else 0.0
@property
def mr(self):
"""
Returns the Mean Recall of all classes.
Returns:
(float): The mean recall of all classes.
"""
return self.r.mean() if len(self.r) else 0.0
@property
def map50(self):
"""
Returns the mean Average Precision (mAP) at an IoU threshold of 0.5.
Returns:
(float): The mAP50 at an IoU threshold of 0.5.
"""
return self.all_ap[:, 0].mean() if len(self.all_ap) else 0.0
@property
def map75(self):
"""
Returns the mean Average Precision (mAP) at an IoU threshold of 0.75.
Returns:
(float): The mAP50 at an IoU threshold of 0.75.
"""
return self.all_ap[:, 5].mean() if len(self.all_ap) else 0.0
@property
def map(self):
"""
Returns the mean Average Precision (mAP) over IoU thresholds of 0.5 - 0.95 in steps of 0.05.
Returns:
(float): The mAP over IoU thresholds of 0.5 - 0.95 in steps of 0.05.
"""
return self.all_ap.mean() if len(self.all_ap) else 0.0
def mean_results(self):
"""Mean of results, return mp, mr, map50, map."""
return [self.mp, self.mr, self.map50, self.map]
def class_result(self, i):
"""Class-aware result, return p[i], r[i], ap50[i], ap[i]."""
return self.p[i], self.r[i], self.ap50[i], self.ap[i]
@property
def maps(self):
"""MAP of each class."""
maps = np.zeros(self.nc) + self.map
for i, c in enumerate(self.ap_class_index):
maps[c] = self.ap[i]
return maps
def fitness(self):
"""Model fitness as a weighted combination of metrics."""
w = [0.0, 0.0, 0.1, 0.9] # weights for [P, R, mAP@0.5, mAP@0.5:0.95]
return (np.array(self.mean_results()) * w).sum()
def update(self, results):
"""
Updates the evaluation metrics of the model with a new set of results.
Args:
results (tuple): A tuple containing the following evaluation metrics:
- p (list): Precision for each class. Shape: (nc,).
- r (list): Recall for each class. Shape: (nc,).
- f1 (list): F1 score for each class. Shape: (nc,).
- all_ap (list): AP scores for all classes and all IoU thresholds. Shape: (nc, 10).
- ap_class_index (list): Index of class for each AP score. Shape: (nc,).
Side Effects:
Updates the class attributes `self.p`, `self.r`, `self.f1`, `self.all_ap`, and `self.ap_class_index` based
on the values provided in the `results` tuple.
"""
(self.p, self.r, self.f1, self.all_ap, self.ap_class_index, self.p_curve, self.r_curve, self.f1_curve, self.px,
self.prec_values) = results
@property
def curves(self):
"""Returns a list of curves for accessing specific metrics curves."""
return []
@property
def curves_results(self):
"""Returns a list of curves for accessing specific metrics curves."""
return [[self.px, self.prec_values, 'Recall', 'Precision'], [self.px, self.f1_curve, 'Confidence', 'F1'],
[self.px, self.p_curve, 'Confidence', 'Precision'], [self.px, self.r_curve, 'Confidence', 'Recall']]
class DetMetrics(SimpleClass):
"""
This class is a utility class for computing detection metrics such as precision, recall, and mean average precision
(mAP) of an object detection model.
Args:
save_dir (Path): A path to the directory where the output plots will be saved. Defaults to current directory.
plot (bool): A flag that indicates whether to plot precision-recall curves for each class. Defaults to False.
on_plot (func): An optional callback to pass plots path and data when they are rendered. Defaults to None.
names (tuple of str): A tuple of strings that represents the names of the classes. Defaults to an empty tuple.
Attributes:
save_dir (Path): A path to the directory where the output plots will be saved.
plot (bool): A flag that indicates whether to plot the precision-recall curves for each class.
on_plot (func): An optional callback to pass plots path and data when they are rendered.
names (tuple of str): A tuple of strings that represents the names of the classes.
box (Metric): An instance of the Metric class for storing the results of the detection metrics.
speed (dict): A dictionary for storing the execution time of different parts of the detection process.
Methods:
process(tp, conf, pred_cls, target_cls): Updates the metric results with the latest batch of predictions.
keys: Returns a list of keys for accessing the computed detection metrics.
mean_results: Returns a list of mean values for the computed detection metrics.
class_result(i): Returns a list of values for the computed detection metrics for a specific class.
maps: Returns a dictionary of mean average precision (mAP) values for different IoU thresholds.
fitness: Computes the fitness score based on the computed detection metrics.
ap_class_index: Returns a list of class indices sorted by their average precision (AP) values.
results_dict: Returns a dictionary that maps detection metric keys to their computed values.
curves: TODO
curves_results: TODO
"""
def __init__(self, save_dir=Path('.'), plot=False, on_plot=None, names=()) -> None:
"""Initialize a DetMetrics instance with a save directory, plot flag, callback function, and class names."""
self.save_dir = save_dir
self.plot = plot
self.on_plot = on_plot
self.names = names
self.box = Metric()
self.speed = {'preprocess': 0.0, 'inference': 0.0, 'loss': 0.0, 'postprocess': 0.0}
self.task = 'detect'
def process(self, tp, conf, pred_cls, target_cls):
"""Process predicted results for object detection and update metrics."""
results = ap_per_class(tp,
conf,
pred_cls,
target_cls,
plot=self.plot,
save_dir=self.save_dir,
names=self.names,
on_plot=self.on_plot)[2:]
self.box.nc = len(self.names)
self.box.update(results)
@property
def keys(self):
"""Returns a list of keys for accessing specific metrics."""
return ['metrics/precision(B)', 'metrics/recall(B)', 'metrics/mAP50(B)', 'metrics/mAP50-95(B)']
def mean_results(self):
"""Calculate mean of detected objects & return precision, recall, mAP50, and mAP50-95."""
return self.box.mean_results()
def class_result(self, i):
"""Return the result of evaluating the performance of an object detection model on a specific class."""
return self.box.class_result(i)
@property
def maps(self):
"""Returns mean Average Precision (mAP) scores per class."""
return self.box.maps
@property
def fitness(self):
"""Returns the fitness of box object."""
return self.box.fitness()
@property
def ap_class_index(self):
"""Returns the average precision index per class."""
return self.box.ap_class_index
@property
def results_dict(self):
"""Returns dictionary of computed performance metrics and statistics."""
return dict(zip(self.keys + ['fitness'], self.mean_results() + [self.fitness]))
@property
def curves(self):
"""Returns a list of curves for accessing specific metrics curves."""
return ['Precision-Recall(B)', 'F1-Confidence(B)', 'Precision-Confidence(B)', 'Recall-Confidence(B)']
@property
def curves_results(self):
"""Returns dictionary of computed performance metrics and statistics."""
return self.box.curves_results
class SegmentMetrics(SimpleClass):
"""
Calculates and aggregates detection and segmentation metrics over a given set of classes.
Args:
save_dir (Path): Path to the directory where the output plots should be saved. Default is the current directory.
plot (bool): Whether to save the detection and segmentation plots. Default is False.
on_plot (func): An optional callback to pass plots path and data when they are rendered. Defaults to None.
names (list): List of class names. Default is an empty list.
Attributes:
save_dir (Path): Path to the directory where the output plots should be saved.
plot (bool): Whether to save the detection and segmentation plots.
on_plot (func): An optional callback to pass plots path and data when they are rendered.
names (list): List of class names.
box (Metric): An instance of the Metric class to calculate box detection metrics.
seg (Metric): An instance of the Metric class to calculate mask segmentation metrics.
speed (dict): Dictionary to store the time taken in different phases of inference.
Methods:
process(tp_m, tp_b, conf, pred_cls, target_cls): Processes metrics over the given set of predictions.
mean_results(): Returns the mean of the detection and segmentation metrics over all the classes.
class_result(i): Returns the detection and segmentation metrics of class `i`.
maps: Returns the mean Average Precision (mAP) scores for IoU thresholds ranging from 0.50 to 0.95.
fitness: Returns the fitness scores, which are a single weighted combination of metrics.
ap_class_index: Returns the list of indices of classes used to compute Average Precision (AP).
results_dict: Returns the dictionary containing all the detection and segmentation metrics and fitness score.
"""
def __init__(self, save_dir=Path('.'), plot=False, on_plot=None, names=()) -> None:
"""Initialize a SegmentMetrics instance with a save directory, plot flag, callback function, and class names."""
self.save_dir = save_dir
self.plot = plot
self.on_plot = on_plot
self.names = names
self.box = Metric()
self.seg = Metric()
self.speed = {'preprocess': 0.0, 'inference': 0.0, 'loss': 0.0, 'postprocess': 0.0}
self.task = 'segment'
def process(self, tp_b, tp_m, conf, pred_cls, target_cls):
"""
Processes the detection and segmentation metrics over the given set of predictions.
Args:
tp_b (list): List of True Positive boxes.
tp_m (list): List of True Positive masks.
conf (list): List of confidence scores.
pred_cls (list): List of predicted classes.
target_cls (list): List of target classes.
"""
results_mask = ap_per_class(tp_m,
conf,
pred_cls,
target_cls,
plot=self.plot,
on_plot=self.on_plot,
save_dir=self.save_dir,
names=self.names,
prefix='Mask')[2:]
self.seg.nc = len(self.names)
self.seg.update(results_mask)
results_box = ap_per_class(tp_b,
conf,
pred_cls,
target_cls,
plot=self.plot,
on_plot=self.on_plot,
save_dir=self.save_dir,
names=self.names,
prefix='Box')[2:]
self.box.nc = len(self.names)
self.box.update(results_box)
@property
def keys(self):
"""Returns a list of keys for accessing metrics."""
return [
'metrics/precision(B)', 'metrics/recall(B)', 'metrics/mAP50(B)', 'metrics/mAP50-95(B)',
'metrics/precision(M)', 'metrics/recall(M)', 'metrics/mAP50(M)', 'metrics/mAP50-95(M)']
def mean_results(self):
"""Return the mean metrics for bounding box and segmentation results."""
return self.box.mean_results() + self.seg.mean_results()
def class_result(self, i):
"""Returns classification results for a specified class index."""
return self.box.class_result(i) + self.seg.class_result(i)
@property
def maps(self):
"""Returns mAP scores for object detection and semantic segmentation models."""
return self.box.maps + self.seg.maps
@property
def fitness(self):
"""Get the fitness score for both segmentation and bounding box models."""
return self.seg.fitness() + self.box.fitness()
@property
def ap_class_index(self):
"""Boxes and masks have the same ap_class_index."""
return self.box.ap_class_index
@property
def results_dict(self):
"""Returns results of object detection model for evaluation."""
return dict(zip(self.keys + ['fitness'], self.mean_results() + [self.fitness]))
@property
def curves(self):
"""Returns a list of curves for accessing specific metrics curves."""
return [
'Precision-Recall(B)', 'F1-Confidence(B)', 'Precision-Confidence(B)', 'Recall-Confidence(B)',
'Precision-Recall(M)', 'F1-Confidence(M)', 'Precision-Confidence(M)', 'Recall-Confidence(M)']
@property
def curves_results(self):
"""Returns dictionary of computed performance metrics and statistics."""
return self.box.curves_results + self.seg.curves_results
class PoseMetrics(SegmentMetrics):
"""
Calculates and aggregates detection and pose metrics over a given set of classes.
Args:
save_dir (Path): Path to the directory where the output plots should be saved. Default is the current directory.
plot (bool): Whether to save the detection and segmentation plots. Default is False.
on_plot (func): An optional callback to pass plots path and data when they are rendered. Defaults to None.
names (list): List of class names. Default is an empty list.
Attributes:
save_dir (Path): Path to the directory where the output plots should be saved.
plot (bool): Whether to save the detection and segmentation plots.
on_plot (func): An optional callback to pass plots path and data when they are rendered.
names (list): List of class names.
box (Metric): An instance of the Metric class to calculate box detection metrics.
pose (Metric): An instance of the Metric class to calculate mask segmentation metrics.
speed (dict): Dictionary to store the time taken in different phases of inference.
Methods:
process(tp_m, tp_b, conf, pred_cls, target_cls): Processes metrics over the given set of predictions.
mean_results(): Returns the mean of the detection and segmentation metrics over all the classes.
class_result(i): Returns the detection and segmentation metrics of class `i`.
maps: Returns the mean Average Precision (mAP) scores for IoU thresholds ranging from 0.50 to 0.95.
fitness: Returns the fitness scores, which are a single weighted combination of metrics.
ap_class_index: Returns the list of indices of classes used to compute Average Precision (AP).
results_dict: Returns the dictionary containing all the detection and segmentation metrics and fitness score.
"""
def __init__(self, save_dir=Path('.'), plot=False, on_plot=None, names=()) -> None:
"""Initialize the PoseMetrics class with directory path, class names, and plotting options."""
super().__init__(save_dir, plot, names)
self.save_dir = save_dir
self.plot = plot
self.on_plot = on_plot
self.names = names
self.box = Metric()
self.pose = Metric()
self.speed = {'preprocess': 0.0, 'inference': 0.0, 'loss': 0.0, 'postprocess': 0.0}
self.task = 'pose'
def process(self, tp_b, tp_p, conf, pred_cls, target_cls):
"""
Processes the detection and pose metrics over the given set of predictions.
Args:
tp_b (list): List of True Positive boxes.
tp_p (list): List of True Positive keypoints.
conf (list): List of confidence scores.
pred_cls (list): List of predicted classes.
target_cls (list): List of target classes.
"""
results_pose = ap_per_class(tp_p,
conf,
pred_cls,
target_cls,
plot=self.plot,
on_plot=self.on_plot,
save_dir=self.save_dir,
names=self.names,
prefix='Pose')[2:]
self.pose.nc = len(self.names)
self.pose.update(results_pose)
results_box = ap_per_class(tp_b,
conf,
pred_cls,
target_cls,
plot=self.plot,
on_plot=self.on_plot,
save_dir=self.save_dir,
names=self.names,
prefix='Box')[2:]
self.box.nc = len(self.names)
self.box.update(results_box)
@property
def keys(self):
"""Returns list of evaluation metric keys."""
return [
'metrics/precision(B)', 'metrics/recall(B)', 'metrics/mAP50(B)', 'metrics/mAP50-95(B)',
'metrics/precision(P)', 'metrics/recall(P)', 'metrics/mAP50(P)', 'metrics/mAP50-95(P)']
def mean_results(self):
"""Return the mean results of box and pose."""
return self.box.mean_results() + self.pose.mean_results()
def class_result(self, i):
"""Return the class-wise detection results for a specific class i."""
return self.box.class_result(i) + self.pose.class_result(i)
@property
def maps(self):
"""Returns the mean average precision (mAP) per class for both box and pose detections."""
return self.box.maps + self.pose.maps
@property
def fitness(self):
"""Computes classification metrics and speed using the `targets` and `pred` inputs."""
return self.pose.fitness() + self.box.fitness()
@property
def curves(self):
"""Returns a list of curves for accessing specific metrics curves."""
return [
'Precision-Recall(B)', 'F1-Confidence(B)', 'Precision-Confidence(B)', 'Recall-Confidence(B)',
'Precision-Recall(P)', 'F1-Confidence(P)', 'Precision-Confidence(P)', 'Recall-Confidence(P)']
@property
def curves_results(self):
"""Returns dictionary of computed performance metrics and statistics."""
return self.box.curves_results + self.pose.curves_results
class ClassifyMetrics(SimpleClass):
"""
Class for computing classification metrics including top-1 and top-5 accuracy.
Attributes:
top1 (float): The top-1 accuracy.
top5 (float): The top-5 accuracy.
speed (Dict[str, float]): A dictionary containing the time taken for each step in the pipeline.
Properties:
fitness (float): The fitness of the model, which is equal to top-5 accuracy.
results_dict (Dict[str, Union[float, str]]): A dictionary containing the classification metrics and fitness.
keys (List[str]): A list of keys for the results_dict.
Methods:
process(targets, pred): Processes the targets and predictions to compute classification metrics.
"""
def __init__(self) -> None:
"""Initialize a ClassifyMetrics instance."""
self.top1 = 0
self.top5 = 0
self.speed = {'preprocess': 0.0, 'inference': 0.0, 'loss': 0.0, 'postprocess': 0.0}
self.task = 'classify'
def process(self, targets, pred):
"""Target classes and predicted classes."""
pred, targets = torch.cat(pred), torch.cat(targets)
correct = (targets[:, None] == pred).float()
acc = torch.stack((correct[:, 0], correct.max(1).values), dim=1) # (top1, top5) accuracy
self.top1, self.top5 = acc.mean(0).tolist()
@property
def fitness(self):
"""Returns mean of top-1 and top-5 accuracies as fitness score."""
return (self.top1 + self.top5) / 2
@property
def results_dict(self):
"""Returns a dictionary with model's performance metrics and fitness score."""
return dict(zip(self.keys + ['fitness'], [self.top1, self.top5, self.fitness]))
@property
def keys(self):
"""Returns a list of keys for the results_dict property."""
return ['metrics/accuracy_top1', 'metrics/accuracy_top5']
@property
def curves(self):
"""Returns a list of curves for accessing specific metrics curves."""
return []
@property
def curves_results(self):
"""Returns a list of curves for accessing specific metrics curves."""
return []