Python + OpenCV 名称未定义

Question

我将 Open CV 中的源代码示例用于 Python 文档，如下所示：

import numpy as np
import cv2
import glob

# termination criteria in this, 30 max number of iterations, 0.001 minimum accuracy
# CV_TERMCRIT_ITER or CV_TERMCRIT_EPS, tells the algorithm that we want to terminate either after some number of iterations or when the convergence metric reaches some small value (respectively).
# The next two arguments set the values at which one, the other, or both of these criteria should terminate the algorithm.
criteria = (cv2.TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER, 30, 0.001)

# prepare object points, like (0,0,0), (1,0,0), (2,0,0), ..., (6,5,0)
objp = np.zeros((6*9,3), np.float32)
objp[:,:2] = np.mgrid[0:9,0:6].T.reshape(-1,2)

# Arrays to store object points and image points from all the images.
objpoints = [] # 3d point in real world space
imgpoints = [] # 2d points in image plane.

images = glob.glob('*.jpg')

# fname= 'C:\Users\Bender\Desktop\fotospayloads\'

for fname in images:
    img = cv2.imread(fname)
    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

    # Find the chess board corners
    ret, corners = cv2.findChessboardCorners(gray, (9,6), None)

    # If found, add object points, image points (after refining them)
    if ret == True:
        objpoints.append(objp)

        corners2 = cv2.cornerSubPix(gray, corners, (11,11), (-1,-1), criteria)
        imgpoints.append(corners2)

        # Draw and display the corners
        img = cv2.drawChessboardCorners(img, (9,6), corners2, ret)
        cv2.imshow('img', img)
        cv2.waitKey(500)

cv2.destroyAllWindows()

rms, mtx, dist, rvecs, tvecs = cv2.calibrateCamera(objpoints, imgpoints, gray.shape[::-1], None, None)

不幸的是，当我运行源代码时，出现以下错误： "NameError: name 'gray' is not defined"（第 50 行）。

非常感谢任何帮助。

谢谢

以撒

Answer 1

您的脚本所在的文件夹中没有图像，这就是为什么 glob.glob('.jpg') 没有 return 任何文件并且没有创建灰色对象的原因。

Python + OpenCV 名称未定义

Python + OpenCV name not defined

python

opencv

nameerror