python摄像头采集视频图像时出现cvtcolor错误,（-215：断言失败）函数'cv :: cvtColor'中的！_src.empty（）...

I am trying to recognize text from an image to then have the text outputted;

however, this error spits out:

Traceback (most recent call last):

File "C:/Users/Benji's Beast/AppData/Local/Programs/Python/Python37-32/imageDet.py", line 41, in

print(get_string(src_path + "cont.jpg") )

File "C:/Users/Benji's Beast/AppData/Local/Programs/Python/Python37-32/imageDet.py", line 15, in get_string

img = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

cv2.error: OpenCV(3.4.4) C:\projects\opencv-python\opencv\modules\imgproc\src\color.cpp:181: error: (-215:Assertion failed) !_src.empty() in function 'cv::cvtColor'

The image resolution is 1371x51.

I have tried changing the "/" on src_path to "\" but that didn't work.

Any ideas?

Here is my code:

import cv2

import numpy as np

import pytesseract

from PIL import Image

from pytesseract import image_to_string

# Path of working folder on Disk

src_path = "C:/Users/Benji's Beast/Desktop/image.PNG"

def get_string(img_path):

# Read image with opencv

img = cv2.imread(img_path)

# Convert to gray

img = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

# Apply dilation and erosion to remove some noise

kernel = np.ones((1, 1), np.uint8)

img = cv2.dilate(img, kernel, iterations=1)

img = cv2.erode(img, kernel, iterations=1)

# Write image after removed noise

cv2.imwrite(src_path + "removed_noise.png", img)

# Apply threshold to get image with only black and white

#img = cv2.adaptiveThreshold(img, 255, cv2.ADAPTIVE_THRESH_GAUSSIAN_C, cv2.THRESH_BINARY, 31, 2)

# Write the image after apply opencv to do some ...

cv2.imwrite(src_path + "thres.png", img)

# Recognize text with tesseract for python

result = pytesseract.image_to_string(Image.open(src_path + "thres.png"))

# Remove template file

#os.remove(temp)

return result

print('--- Start recognize text from image ---')

print(get_string(src_path + "cont.jpg") )

print("------ Done -------")

I have no idea how to fix this,

thanks.

解决方案

This means you are passing a Uninitialized variable to

> cv2.cvtColor()

After this statement:

# Read image with opencv

img = cv2.imread(img_path)

Can you try to print the img variable before passing to cv2.cvtColor() function

> print(img) or print(img.shape)

to make sure function call to read the image is successful