图像分割指标python代码

好的，以下是常用的图像分割指标的 Python 代码实现：

1. Mean Intersection over Union (mIoU)

import numpy as np

def mean_iou(y_true, y_pred):
    num_classes = y_pred.shape[-1]
    iou = []
    for class_id in range(num_classes):
        y_true_class = y_true[..., class_id]
        y_pred_class = y_pred[..., class_id]
        intersection = np.logical_and(y_true_class, y_pred_class).sum()
        union = np.logical_or(y_true_class, y_pred_class).sum()
        if union == 0:
            iou.append(0)
        else:
            iou.append(intersection / union)
    return np.mean(iou)

2. Dice coefficient

def dice_coef(y_true, y_pred, smooth=1):
    intersection = np.sum(y_true * y_pred)
    return (2. * intersection + smooth) / (np.sum(y_true) + np.sum(y_pred) + smooth)

3. F1 score

def f1_score(y_true, y_pred):
    tp = np.sum(y_true * y_pred)
    fp = np.sum((1 - y_true) * y_pred)
    fn = np.sum(y_true * (1 - y_pred))
    precision = tp / (tp + fp)
    recall = tp / (tp + fn)
    return 2 * ((precision * recall) / (precision + recall))