import numpy as np
import cv2

def color_space(image):
 """色彩空間轉(zhuǎn)換"""
 hsv = cv2.cvtColor(image, cv2.COLOR_BGR2HSV)
 hls = cv2.cvtColor(image, cv2.COLOR_BGR2HLS)
 ycrcb = cv2.cvtColor(image, cv2.COLOR_BGR2YCrCb)
 yuv = cv2.cvtColor(image, cv2.COLOR_BGR2YUV)
 h1 = np.hstack((hsv, hls))
 h2 = np.hstack((ycrcb, yuv))
 stack = np.vstack((h1, h2))
 return stack

# 讀取圖片
img = cv2.imread("beautiful_girl.jpg")
# 不同色彩空間
stack = color_space(img)
# 圖片展示
cv2.imshow("stack", stack)
cv2.waitKey(0)
cv2.destroyAllWindows()

import numpy as np
import cv2

def video_capture():
 """讀取視頻"""
 
 # 從攝像頭獲取視頻
 capture = cv2.VideoCapture(0)
 
 # 循環(huán)
 while (True):
  # 讀取一幀
  ret, frame = capture.read()
  # 如果讀取幀, 返回值為False, break
  if ret == False:
break
  # 設(shè)置顏色閾值
  lower = np.array([0, 0, 0])
  upper = np.array([100, 100, 255])
  mask = cv2.inRange(frame, lowerb=lower, upperb=upper)
  
  # 展示
  cv2.imshow("video", frame)
  cv2.imshow("mask", mask)
  # 按下q鍵退出
  if cv2.waitKey(20) & 0xFF == ord("q"):
break

if __name__ == "__main__":
 video_capture()