Python AttributeError: 'NoneType' 对象没有属性 'shape'
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AttributeError: 'NoneType' object has no attribute 'shape'
提问by AK47
import numpy as np
import cv2
from matplotlib import pyplot as plt
img = cv2.imread('AB.jpg')
mask = np.zeros(img.shape[:2] , np.uint8)
bgdModel = np.zeros((1,65), np.float64)
fgdModel = np.zeros((1,65), np.float64)
rect = (300 , 120 , 470 , 350)
#this modifies mask
cv2.grabCut(img,mask,rect,bgdModel, fgdModel , 5 , cv2.GC_INIT_WITH_RECT)
#If mask==2 or mask==1 , mask2 get 0, otherwise it gets 1 as 'uint8' type
mask2 = np.where((mask==2) | (mask==0),0,1).astype('uint8')
#adding additional dimension for rgb to the mask, by default it gets 1
#multiply with input image to get the segmented image
img_cut = img*mask2[: , : , np.newaxis]
plt.subplot(211),plt.imshow(img)
plt.title('Input Image') , plt.xticks([]),plt.yticks([])
plt.subplot(212),plt.imshow(img_cut)
plt.title('Grab cut'), plt.xticks([]),plt.yticks([])
plt.show()
on compiling I get this error :
编译时出现此错误：
python img.py AB.jpg
Traceback (most recent call last):
File "img.py", line 6, in <module>
mask = np.zeros(img.shape[:2] , np.uint8)
AttributeError: 'NoneType' object has no attribute 'shape'
回答by Emanuele Cipolla
First of all
首先
python img.py AB.jpg
will not work as you expect (load AB.jpg from the current directory). The file to load is hardcoded in line 6 of the provided example: to work as intended, it should be something like this:
不会按预期工作（从当前目录加载 AB.jpg）。要加载的文件在提供的示例的第 6 行中进行了硬编码：要按预期工作，它应该是这样的：
import sys
img = cv2.imread(sys.argv[1])
The error is returned because AB.jpg does not exist in the directory img.py is being run from (the current working directory), and there is no verification for a missing file before trying to read it.
返回错误是因为在运行 img.py 的目录（当前工作目录）中不存在 AB.jpg，并且在尝试读取之前没有验证丢失的文件。
回答by I.Newton
Answering, because the community brought it back. Adding my two objects (cents).
回答，因为社区把它带回来了。添加我的两个对象（美分）。
The only reason you see that error is because you are trying to get information or perform operations on an object that doesn't exist in the first place. To check, try printing the object. Like, adding -
您看到该错误的唯一原因是您试图获取信息或对最初不存在的对象执行操作。要检查，请尝试打印对象。喜欢，添加 -
print img # such as this case
print contours # if you are working with contours and cant draw one
print frame # if you are working with videos and it doesn't show
gives you a None. That means you haven't read it properly. Either the image name you gave does not exist or the path to it is wrong. If you find such an error here's the quick things to do-
给你一个 None。这意味着你没有正确阅读它。您提供的图像名称不存在或路径错误。如果你发现这样的错误这里是快速的事情做 -
- Check the path or bring your image to the working directory
- Check the name you gave is right (including the extension- .jpg, .png etc)
- Put the entire code in a if statement with the object and the code to proceed if true
- Will add more if suggested in the comments.
- 检查路径或将您的图像带到工作目录
- 检查您提供的名称是否正确（包括扩展名 - .jpg、.png 等）
- 将整个代码与对象和代码放在 if 语句中，如果为真则继续
- 如果在评论中提出建议，将添加更多。
