diff --git a/supervision/metrics/detection.py b/supervision/metrics/detection.py index de1ffe47..39bead32 100644 --- a/supervision/metrics/detection.py +++ b/supervision/metrics/detection.py @@ -464,9 +464,6 @@ class ConfusionMatrix: return fig -import torch - - @dataclass(frozen=True) class MeanAveragePrecision: map: float @@ -572,7 +569,7 @@ class MeanAveragePrecision: stats = [np.concatenate(x, 0) for x in zip(*stats)] if len(stats) and stats[0].any(): - tp, fp, p, r, f1, ap, ap_class = ap_per_class(*stats, names=classes) + tp, fp, p, r, f1, ap, ap_class = MeanAveragePrecision.ap_per_class(*stats, names=classes) ap50, ap = ap[:, 0], ap.mean(1) # AP@0.5, AP@0.5:0.95 mp, mr, map50, map = p.mean(), r.mean(), ap50.mean(), ap.mean() @@ -633,82 +630,84 @@ class MeanAveragePrecision: matches = matches[np.unique(matches[:, 0], return_index=True)[1]] return matches + @staticmethod + def compute_ap(recall, precision): + """Compute the average precision, given the recall and precision curves + # Arguments + recall: The recall curve (list) + precision: The precision curve (list) + # Returns + Average precision, precision curve, recall curve + """ + # Append sentinel values to beginning and end + mrec = np.concatenate(([0.0], recall, [1.0])) + mpre = np.concatenate(([1.0], precision, [0.0])) -def ap_per_class(tp, conf, pred_cls, target_cls, eps=1e-16): - i = np.argsort(-conf) - tp, conf, pred_cls = tp[i], conf[i], pred_cls[i] + # Compute the precision envelope + mpre = np.flip(np.maximum.accumulate(np.flip(mpre))) - unique_classes, nt = np.unique(target_cls, return_counts=True) - nc = unique_classes.shape[0] # number of classes, number of detections + # 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 - px, py = np.linspace(0, 1, 1000), [] # for plotting - ap, p, r = 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 + return ap, mpre, mrec - # Accumulate FPs and TPs - fpc = (1 - tp[i]).cumsum(0) - tpc = tp[i].cumsum(0) + @staticmethod + def ap_per_class(tp, conf, pred_cls, target_cls, eps=1e-16): + i = np.argsort(-conf) + tp, conf, pred_cls = tp[i], conf[i], pred_cls[i] - # Recall - recall = tpc / (n_l + eps) # recall curve - r[ci] = np.interp( - -px, -conf[i], recall[:, 0], left=0 - ) # negative x, xp because xp decreases + unique_classes, nt = np.unique(target_cls, return_counts=True) + nc = unique_classes.shape[0] # number of classes, number of detections - # Precision - precision = tpc / (tpc + fpc) # precision curve - p[ci] = np.interp(-px, -conf[i], precision[:, 0], left=1) # p at pr_score + px, py = np.linspace(0, 1, 1000), [] # for plotting + ap, p, r = 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 - # AP from recall-precision curve - for j in range(tp.shape[1]): - ap[ci, j], mpre, mrec = compute_ap(recall[:, j], precision[:, j]) + # Accumulate FPs and TPs + fpc = (1 - tp[i]).cumsum(0) + tpc = tp[i].cumsum(0) - # Compute F1 (harmonic mean of precision and recall) - f1 = 2 * p * r / (p + r + eps) + # Recall + recall = tpc / (n_l + eps) # recall curve + r[ci] = np.interp( + -px, -conf[i], recall[:, 0], left=0 + ) # negative x, xp because xp decreases - i = smooth(f1.mean(0), 0.1).argmax() # max F1 index - p, r, f1 = p[:, i], r[:, i], f1[:, i] - 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) + # Precision + precision = tpc / (tpc + fpc) # precision curve + p[ci] = np.interp(-px, -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 = MeanAveragePrecision.compute_ap(recall[:, j], precision[:, j]) + + # Compute F1 (harmonic mean of precision and recall) + f1 = 2 * p * r / (p + r + eps) + + i = MeanAveragePrecision.smooth(f1.mean(0), 0.1).argmax() # max F1 index + p, r, f1 = p[:, i], r[:, i], f1[:, i] + 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) + + @staticmethod + 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 -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 - -def compute_ap(recall, precision): - """Compute the average precision, given the recall and precision curves - # Arguments - recall: The recall curve (list) - precision: The precision curve (list) - # Returns - Average precision, precision curve, recall curve - """ - - # 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