我的 picamera 通常工作正常，但是當(dāng)按照上面的帖子操作時(shí)，我的 picamera 無法工作。這是我的源代碼：from imutils.video import VideoStreamimport argparseimport imutilsimport timeimport cv2import osap = argparse.ArgumentParser()ap.add_argument("-c", "--cascade", required=True,? ? help = "path to where the face cascade resides")ap.add_argument("-o", "--output", required=True,? ? help="path to output directory")args = vars(ap.parse_args())detector = cv2.CascadeClassifier(args["cascade"])print("[INFO] starting video stream...")#vs = VideoStream(src=0).start()?vs = VideoStream(usePiCamera=True).start()time.sleep(2.0)total = 0while True:? ? frame = vs.read()? ? orig = frame.copy()? ? frame = imutils.resize(frame, width=400)? ? rects = detector.detectMultiScale(? ? ? ? cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY), scaleFactor=1.1,?? ? ? ? minNeighbors=5, minSize=(30, 30))? ? for (x, y, w, h) in rects:? ? ? ? cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2)? ? cv2.imshow("Frame", frame)? ? key = cv2.waitKey(1) & 0xFF?? ? if key == ord("k"):? ? ? ? p = os.path.sep.join([args["output"], "{}.png".format(? ? ? ? ? ? str(total).zfill(5))])? ? ? ? cv2.imwrite(p, orig)? ? ? ? total += 1? ? elif key == ord("q"):? ? ? ? breakprint("[INFO] {} face images stored".format(total))print("[INFO] cleaning up...")cv2.destroyAllWindows()vs.stop()當(dāng)我運(yùn)行這段代碼時(shí)，[INFO] starting video stream...出現(xiàn)但攝像頭未出現(xiàn)在 Raspberry Pi 上；而且，當(dāng)我面對(duì)鏡頭時(shí)，[INFO] {} face images stored?[INFO] cleaning up...出現(xiàn)。