Python 如何裁剪帧上的多个感兴趣区域矩形

我正在处理视频输入，其中视频被分为帧。现在我必须在我感兴趣的区域的文本上画一个矩形。所以，我需要在csv文件中存储我在框架上绘制的所有矩形的所有坐标点。我需要从每一帧裁剪出所有的矩形。 我正在发送用python编写的程序。扩展到这一点，我希望每个帧都选择所有矩形

    self.capture = cv2.VideoCapture('ch3_train/Video_2_1_2.mp4')

    # Bounding box reference points and boolean if we are extracting coordinates
    self.image_coordinates = []
    self.extract = False
    self.selected_ROI = False

    self.update()

def update(self):
    while True:

        if self.capture.isOpened():

            # Read frame
            (self.status, self.frame) = self.capture.read()
            for i in range(len(self.frame)):
                cv2.imshow('image', self.frame)
            key = cv2.waitKey(2)



            # Crop image
            if key == ord('c'):
                self.clone = self.frame.copy()
                cv2.namedWindow('image')
                cv2.setMouseCallback('image', self.extract_coordinates)
                while True:
                    key = cv2.waitKey(2)
                    cv2.imshow('image', self.clone)

                    # Crop and display cropped image
                    if key == ord('c'):
                        self.crop_ROI()
                        self.show_cropped_ROI()

                    # Resume video
                    if key == ord('r'):
                        break
            # Close program with keyboard 'q'
            if key == ord('q'):

                cv2.destroyAllWindows()
                self.capture.release()
                exit(1)
        else:
           sys.exit()

         #pass

def extract_coordinates(self, event, x, y, flags, parameters):
    # Record starting (x,y) coordinates on left mouse button click
    if event == cv2.EVENT_LBUTTONDOWN:
        self.image_coordinates = [(x,y)]
        self.extract = True

    # Record ending (x,y) coordintes on left mouse bottom release
    elif event == cv2.EVENT_LBUTTONUP:
        self.image_coordinates.append((x,y))
        self.extract = False

        self.selected_ROI = True



         #   (x1,y1,x2,y2)=[int(v) for v in f ]
        # Draw rectangle around ROI
        cv2.rectangle(self.clone, self.image_coordinates[0], self.image_coordinates[1], (0,255,0), 2)
        '''
        while  self.selected_ROI:
            x1 = self.image_coordinates[0][0]
            y1 = self.image_coordinates[0][1]
            x2 = self.image_coordinates[1][0]
            y2 = self.image_coordinates[1][1]

            with open ('train_annotations_bbox.csv',mode='w') as bboxfile:
                bboxwriter=csv.writer(bboxfile,delimiter=',', quotechar='"', quoting=csv.QUOTE_MINIMAL)
                bboxwriter.writerow(['Xmin','Xmax','Ymin','Ymax'])#[self.image_coordinators[1],self.image_coordinators[0]])
                bboxwriter.writerow([x1*0.001,y1*0.001,x2*0.001,y2*0.001])
        '''
        #for i in event:
         #   cv2.imwrite("frame%d"+i+".jpg",self.clone)
    # Clear drawing boxes on right mouse button click
    elif event == cv2.EVENT_RBUTTONDOWN:
        self.clone = self.frame.copy()
        self.selected_ROI = False

def crop_ROI(self):
    if self.selected_ROI:


        self.cropped_image = self.frame.copy()

        x1 = self.image_coordinates[0][0]
        y1 = self.image_coordinates[0][1]
        x2 = self.image_coordinates[1][0]
        y2 = self.image_coordinates[1][1]

        self.cropped_image = self.cropped_image[y1:y2, x1:x2]


        print('Cropped image: {} {}'.format(self.image_coordinates[0], self.image_coordinates[1]))
        #fromCenter=False
        #ROIs=cv2.selectROIs('Select ROIs',self.selected_ROI,fromCenter)
        #for i, ctr in enumerate(self.selected_ROI):
         #   cv2.imshow('roi'+str(i),self.cropped_image)

    else:
        print('Select ROI to crop before cropping')

def show_cropped_ROI(self):
    cv2.imshow('cropped image', self.cropped_image)

我希望输出是在矩形上循环以将其坐标点存储在csv文件中。但实际输出仅存储csv文件中选定的最后一个矩形