OPENCV摄像机边界被视为对象，仅在跨路径时检测到对象

Question

我试图用相机检测对象。但是，只有外边界变成绿色，并且一旦将物体切开外边框，就会检测到它们。

https://i.sstatic.net/9tiqg.jpg 当它切开轮廓时，但不会检测到矩形。

如您所知，只有边界是绿色的，一旦对象将边框切割成一个物体。如果我要在屏幕中间放置其他东西，而这些东西不触及大纲边界，则不被视为对象。

我的代码：

import math
import numpy as np
import cv2 as cv
from threading import *

class robotVision(Thread):

    def run(self):
        self.cap = cv.VideoCapture(0)
        if not self.cap.isOpened():
            print("Cannot open camera")
            exit()
        while True:
            # Capture frame-by-frame
            self.ret, self.frame = self.cap.read()

            if not self.ret:
                print("Can't receive frame (stream end?). Exiting ...")
                break

            self.detectCookie()

            self.imshow()

            if cv.waitKey(1) == ord('q'):
                self.releaseStream()
                break

    def detectCookie(self):
        # turn scene gray and put a threshold on noise
        self.gray = cv.cvtColor(self.frame, cv.COLOR_BGR2GRAY)
        self.blur = cv.GaussianBlur(self.gray,(39, 39), 0)
        _, self.thresh = cv.threshold(self.blur, 75, 255, 0, cv.THRESH_BINARY)
        self.dilated = cv.dilate(self.thresh, (7, 7), iterations = 3)
        self.findContours()

        for cnt in self.contours:
            area = cv.contourArea(cnt)
            perimeter = cv.arcLength(cnt, True)

            if (perimeter != 0 and area != 0):
                #the rounding -> how round it is
                formFactor = 4 * math.pi * area / perimeter**2

            if (area > 100):
                self.drawContours(cnt)

    def releaseStream(self):
        # When everything done, release the capture
        self.cap.release()
        cv.destroyAllWindows()

    def imshow(self):
        cv.imshow("Gray capture (First cycle)", self.gray)
        cv.imshow("Blur capture (Second cycle)", self.blur)
        cv.imshow("Thresh capture (Third cycle)", self.thresh)
        cv.imshow("Dilated capture (Fourth cycle)", self.dilated)
        cv.imshow("Video capture (Final result)", self.frame)

    def findContours(self):
        self.contours, self.hierarchy = cv.findContours(self.dilated, cv.RETR_EXTERNAL, cv.CHAIN_APPROX_NONE)

    def drawContours(self, target = "default"):
        if (target == "default"):
            cv.drawContours(self.frame, self.contours, -1, (0,255,0), 3)
        elif (isinstance(target, list)):
            cv.drawContours(self.frame, target, -1, (0,255,0), 3)
        else:
            cv.drawContours(self.frame, [target], -1, (0,255,0), 3)

我的问题：

我如何删除外线并检测对象而无需对象切开外线以被视为对象。