如何知道opencv python是否检测到颜色

Question

如下所示，图像中会检测到蓝色，并弹出新图像。而不是我想知道是否检测到颜色而不是显示图像。像这样的东西，

if blueColor in image:
    print "blue color detected"

文档中的原始代码。

import cv2
import numpy as np

cap = cv2.VideoCapture(0)
while(1):

    # Take each frame
    _, frame = cap.read()

    # Convert BGR to HSV
    hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)

    # define range of blue color in HSV
    lower_blue = np.array([110,50,50])
    upper_blue = np.array([130,255,255])

    # Threshold the HSV image to get only blue colors
    mask = cv2.inRange(hsv, lower_blue, upper_blue)

    # Bitwise-AND mask and original image
    res = cv2.bitwise_and(frame,frame, mask= mask)

    cv2.imshow('frame',frame)
    cv2.imshow('mask',mask)
    cv2.imshow('res',res)
    k = cv2.waitKey(5) & 0xFF
    if k == 27:
        break

cv2.destroyAllWindows（）