opencv鼠标选择roi区域

您好！要使用OpenCV选择ROI区域，可以使用鼠标回调函数和OpenCV提供的ROI选择函数。下面是一个基本的示例代码：

import cv2

# 创建鼠标回调函数
def select_roi(event, x, y, flags, param):
    global roi, roi_selected, start_x, start_y, end_x, end_y
    
    if event == cv2.EVENT_LBUTTONDOWN:
        roi_selected = False
        start_x, start_y = x, y
        
    elif event == cv2.EVENT_MOUSEMOVE:
        if flags == cv2.EVENT_FLAG_LBUTTON:
            img_copy = img.copy()
            cv2.rectangle(img_copy, (start_x, start_y), (x, y), (0, 255, 0), 2)
            cv2.imshow("image", img_copy)
            
    elif event == cv2.EVENT_LBUTTONUP:
        end_x, end_y = x, y
        roi = img[start_y:end_y, start_x:end_x]
        roi_selected = True
        cv2.destroyAllWindows()

# 读取图像
img = cv2.imread("image.jpg")

# 创建窗口并绑定鼠标回调函数
cv2.namedWindow("image")
cv2.setMouseCallback("image", select_roi)

# 显示图像并等待选择ROI
while True:
    cv2.imshow("image", img)
    key = cv2.waitKey(1) & 0xFF
    if roi_selected:
        break

# 显示选择的ROI
cv2.imshow("ROI", roi)
cv2.waitKey(0)
cv2.destroyAllWindows()

该代码可以打开一张图像，然后通过鼠标拖拽选择ROI区域，并显示选择的ROI。您可以根据需要修改代码以适应您的应用场景。