1. My codes are below for the control using OpenCV to identify a particular colo

Question

1. My codes are below for the control using OpenCV to identify a particular color:

2. The code in italics and close to the bottom with the asterisk is what I need help with. I want the color detected to control a pair of thrusters with the while and else statement. It detects the red color but does not do anything. If it does not detect a color it does nothing too.

#thresh = cv2.inRange(hsv,np.array((0, 200, 200)), np.array((20, 255, 255)))
  
lower = np.array([4,10,120],dtype="uint8")
  
upper = np.array([90,100,255], dtype="uint8")
  
thresh = cv2.inRange(blur, lower, upper)
thresh2 = thresh.copy()
  
# find contours in the threshold image
image, contours,hierarchy = cv2.findContours(thresh,cv2.RETR_LIST,cv2.CHAIN_APPROX_SIMPLE)
  
# finding contour with maximum area and store it as best_cnt
max_area = 0
best_cnt = 1
for cnt in contours:
area = cv2.contourArea(cnt)
if area > max_area:
max_area = area
best_cnt = cnt
  
# finding centroids of best_cnt and draw a circle there
M = cv2.moments(best_cnt)
cx,cy = int(M['m10']/M['m00']), int(M['m01']/M['m00'])
#if best_cnt>1:
cv2.circle(blur,(cx,cy),10,(100,100,255),-1)
cv2.putText(blur, "Red Detected", (cx - 20, cy - 20),
cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255, 255, 255), 2)
# show the frame
cv2.imshow("Frame", blur)
#cv2.imshow('thresh',thresh2)
key = cv2.waitKey(1) & 0xFF

# clear the stream in preparation for the next frame
rawCapture.truncate(0)
  
*while (thresh = cv2.inRange(blur, lower, upper)):
Thrusters_control.forward()
else:
Thrusters_control.turn_right()*
  
  
# if the `q` key was pressed, break from the loop
if key == ord("q"):
break

Explanation / Answer

camera = PiCamera()

camera.resolution = (640, 480)

camera.framerate = 50

camera.hflip = True

rawCapture = PiRGBArray(camera, size=(640, 480))

time.sleep(0.1)

        image = frame.array

        blur = cv2.blur(image, (3,3))

        lower = np.array([76,31,4],dtype="uint8")

                upper = np.array([210,90,70], dtype="uint8")

        thresh = cv2.inRange(blur, lower, upper)

        thresh2 = thresh.copy()

        image, contours,hierarchy = cv2.findContours(thresh,cv2.RETR_LIST,cv2.CHAIN_APPROX_SIMPLE)

        max_area = 0

        best_cnt = 1

        for cnt in contours:

                area = cv2.contourArea(cnt)

                if area > max_area:

                        max_area = area

                        best_cnt = cnt

        M = cv2.moments(best_cnt)

        cx,cy = int(M['m10']/M['m00']), int(M['m01']/M['m00'])

        cv2.circle(blur,(cx,cy),10,(0,0,255),-1)

        cv2.imshow("Frame", blur)

        key = cv2.waitKey(1) & 0xFF

        rawCapture.truncate(0)

        if key == ord("q"):

            break

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