I'；我正在学习关于[python+；opencv+；mediapipe]手动跟踪的教程，发现以下错误： cv2.error:OpenCV（4.5.1）C:\Users\appveyor\AppData\Local\Temp\1\p

I'；我正在学习关于[python+；opencv+；mediapipe]手动跟踪的教程，发现以下错误： cv2.error:OpenCV（4.5.1）C:\Users\appveyor\AppData\Local\Temp\1\pip-req-build-wvn_it83\OpenCV\modules\imgproc\src\color.cpp:182:错误：（-215:断言失败）_函数“cv:：cvtColor”中的src.empty（）

import mediapipe as mp
import time
 
cap = cv2.VideoCapture(1)
 
mpHands = mp.solutions.hands
hands = mpHands.Hands()
mpDraw = mp.solutions.drawing_utils
 
pTime = 0
cTime = 0
 
while True:
    success, img = cap.read()
    imgRGB = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
    results = hands.process(imgRGB)
    # print(results.multi_hand_landmarks)
 
    if results.multi_hand_landmarks:
        for handLms in results.multi_hand_landmarks:
            for id, lm in enumerate(handLms.landmark):
                # print(id, lm)
                h, w, c = img.shape
                cx, cy = int(lm.x * w), int(lm.y * h)
                print(id, cx, cy)
                # if id == 4:
                cv2.circle(img, (cx, cy), 15, (255, 0, 255), cv2.FILLED)
 
            mpDraw.draw_landmarks(img, handLms, mpHands.HAND_CONNECTIONS)
 
    cTime = time.time()
    fps = 1 / (cTime - pTime)
    pTime = cTime
 
    cv2.putText(img, str(int(fps)), (10, 70), cv2.FONT_HERSHEY_PLAIN, 3,
                (255, 0, 255), 3)
 
    cv2.imshow("Image", img)
    cv2.waitKey(1)