python調用攝像頭拍照並保存

import cv2
import os
#引入庫
 
print("=============================================")
print("=  熱鍵(請在攝像頭的窗口使用)：             =")
print("=  z: 更改存儲目錄                          =")
print("=  x: 拍攝圖片                              =")
print("=  q: 退出                                  =")
print("=============================================")
#提醒用戶操作字典
 
class_name = input("請輸入存儲目錄（python安裝目錄下才行，如：d:\python\py_image)：")
while os.path.exists(class_name):
    class_name = input("目錄已存在！請輸入存儲目錄：")
os.mkdir(class_name)
#存儲
 
index = 1
cap = cv2.VideoCapture(0 + cv2.CAP_DSHOW)
width = 640
height = 480
w = 360
cap.set(cv2.CAP_PROP_FRAME_WIDTH, width)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT, height)
crop_w_start = (width-w)//2
crop_h_start = (height-w)//2
print(width, height)
#設置特定值
 
while True:
    ret, frame = cap.read()
   
    frame = frame[crop_h_start:crop_h_start+w, crop_w_start:crop_w_start+w]
    #沒理解？
 
    frame = cv2.flip(frame,1,dst=None)
    #鏡像顯示
    cv2.imshow("capture", frame)
    #顯示
 
    input = cv2.waitKey(1) & 0xFF
    if input == ord('z'):
        class_name = input("請輸入存儲目錄：")
        while os.path.exists(class_name):
            class_name = input("目錄已存在！請輸入存儲目錄：")
        os.mkdir(class_name)
    #存儲
 
    elif input == ord('x'):
        cv2.imwrite("%s/%d.jpeg" % (class_name, index),
                    cv2.resize(frame, (224, 224), interpolation=cv2.INTER_AREA))
        print("%s: %d 張圖片" % (class_name, index))
        index += 1
    #？
    if input == ord('q'):
        break
    #退出
        
cap.release()
cv2.destroyAllWindows()
    #關閉窗口