OpenCV：src 不是一个数值元组

Question

我写了一个用Python做颜色检测的程序。但是在'Erode'这一行总是出错。以下是我程序的一部分。谢谢。

# Convert the image to a Numpy array since most cv2 functions
# require Numpy arrays.
frame = np.array(frame, dtype=np.uint8)

threshold = 0.05
#blur the image
frame=cv2.blur(frame, (5,5))
#Convert from BGR to HSV
hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)
#split into 3
h, s, v= cv2.split(hsv)
#red color
s = cv2.threshold(h, 15, 1, cv2.THRESH_BINARY_INV)#1-15,x>15 y=0
h = cv2.threshold(h, 245, 1, cv2.THRESH_BINARY)#245-255 x>245 y=1
h = h + s
kernel = cv2.getStructuringElement(cv2.MORPH_RECT,(3, 3)) 
h = cv2.erode(h, kernel)
v = cv2.sumElems(h)

Answer 1

试试这个：

_,h = cv2.threshold(h, 245, 1, cv2.THRESH_BINARY) #245-255 x>245 y=1
_,s = cv2.threshold(h, 15, 1, cv2.THRESH_BINARY_INV) #1-15,x>15 y=0

cv2.threshold 会返回两个值： http://docs.opencv.org/modules/imgproc/doc/miscellaneous_transformations.html#cv2.threshold

cv2.threshold(src, thresh, maxval, type[, dst]) → retval, dst

你漏掉了第二个值 dst，如果在表达式中不写这个，你只会得到 retval 这个值，而这个值并不是一张图片。