错误代码：OpenCV（4.0.0）C：\项目\opencv-python\opencv\模块\图像处理\源代码\颜色. cpp：181：错误：（-215：Assert失败）!_src. empty（）在函数"cv：：cvtColor"中
参考代码：
http://blog.tramvm.com/2017/05/recognize-text-from-image-with-python.html
这是python代码用于从图像中提取文本
当我试图运行代码时，我得到了上述错误
代码：

import cv2
import numpy as np
import pytesseract
from PIL import Image

# Path of working folder on Disk
src_path = "C:\\Users\\preetha\\PycharmProjects\\OCR"

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 + "1.png"))

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

我也尝试将路径目录更改为"/"或""，但仍然没有任何结果...请提供任何解决方案？