import numpy as np
import cv2
font= cv2.FONT_HERSHEY_SIMPLEX
lower_red=np.array([0,127,128])#紅色閾值下界
higher_red=np.array([10,255,255])#紅色閾值上界
lower_green=np.array([35,110,106])#綠色閾值下界
higher_green=np.array([77,255,255])#綠色閾值上界
cap=cv2.VideoCapture(0)#打開(kāi)電腦內(nèi)置攝像頭
if(cap.isOpened()):
 while(True):
  ret,frame=cap.read()#按幀讀取，這是讀取一幀
  img_hsv=cv2.cvtColor(frame,cv2.COLOR_BGR2HSV)
  mask_red=cv2.inRange(img_hsv,lower_red,higher_red)#可以認(rèn)為是過(guò)濾出紅色部分，獲得紅色的掩膜
  mask_green=cv2.inRange(img_hsv,lower_green,higher_green)#獲得綠色部分掩膜
  mask_green = cv2.medianBlur(mask_green, 7) # 中值濾波
  mask_red = cv2.medianBlur(mask_red, 7) # 中值濾波
  mask=cv2.bitwise_or(mask_green,mask_red)#三部分掩膜進(jìn)行按位或運(yùn)算
  image1,cnts1,hierarchy1=cv2.findContours(mask_red,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)#輪廓檢測(cè)
  image3,cnts3,hierarchy3=cv2.findContours(mask_green,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)

  for cnt in cnts1:
   (x,y,w,h)=cv2.boundingRect(cnt)#該函數(shù)返回矩陣四個(gè)點(diǎn)
   cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 0, 255), 2)#將檢測(cè)到的顏色框起來(lái)
   cv2.putText(frame,'red',(x,y-5),font,0.7,(0,0,255),2)

  for cnt in cnts3:
   (x, y, w, h) = cv2.boundingRect(cnt) # 該函數(shù)返回矩陣四個(gè)點(diǎn)
   cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2) # 將檢測(cè)到的顏色框起來(lái)
   cv2.putText(frame, 'green', (x, y - 5), font, 0.7, (0,255,0), 2)
  cv2.imshow('frame',frame)
  k=cv2.waitKey(20)&0xFF
  if k ==27:
   break

cv2.waitKey(0)
cv2.destroyAllWindows()