python - exceptions.TypeError : src is not a numpy array, 既不是标量

Question

import cv2
import numpy as np

def imageMoments(img):
    #Single channel(8 bit or floating point 2D array)  
    read_original = cv2.imread(img)

    ret,thresh = cv2.threshold(img, 127, 255, 0)
    contours, hierarchy = cv2.findContours(thresh, cv2.RETR_LIST, cv2.CHAIN_APPROX_NONE)
    cnt = contours[0]

    M = cv2.moments(cnt)
    print M

    cx = int(M[’m10’]/M[’m00’])
    cy = int(M[’m01’]/M[’m00’])
    return

我得到了错误

src is not a numpy array, neither a scalar

Answer 1

cv2.threshold 需要一个灰度图像 作为参数，而不是表示文件名的字符串。因此，替换:

read_original = cv2.imread(img)
ret,thresh = cv2.threshold(img, 127, 255, 0)

与:

read_original = cv2.imread(img)
imgray = cv2.cvtColor(read_original,cv2.COLOR_BGR2GRAY)
ret,thresh = cv2.threshold(imgray, 127, 255, 0)

在原始代码中，字符串 img 作为参数传递给 threshold。在修改后的代码中，threshold 的参数改为灰度图像 imgray。