pytesseract.image_to_string（）总是会产生一个错误

Question

I am doing a project to solve captcha using python.I am using pytesseract module for that.This script works well it also creates new image file by modifying it but always creates an error while interpretation of line text = pytesseract.image_to_string(Image.open(filename)) to extract text from new temporary created image file.I'm using the following script temporary image created for extraction of text

# import the necessary packages
from PIL import Image
import pytesseract
import argparse
import cv2
import os

# construct the argument parse and parse the arguments
ap = argparse.ArgumentParser()
ap.add_argument("-i", "--image", required=True,
help="path to input image to be OCR'd")
ap.add_argument("-p", "--preprocess", type=str, default="thresh",
help="type of preprocessing to be done")
args = vars(ap.parse_args())

# load the example image and convert it to grayscale
image = cv2.imread(args["image"])
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

# check to see if we should apply thresholding to preprocess the
# image
if args["preprocess"] == "thresh":
    gray = cv2.threshold(gray, 0, 255,
    cv2.THRESH_BINARY | cv2.THRESH_OTSU)[1]

# make a check to see if median blurring should be done to remove
# noise
elif args["preprocess"] == "blur":
    gray = cv2.medianBlur(gray, 3)

# write the grayscale image to disk as a temporary file so we can
# apply OCR to it
filename = "{}.png".format(os.getpid())
cv2.imwrite(filename, gray)

# load the image as a PIL/Pillow image, apply OCR, and then delete
# the temporary file
text = pytesseract.image_to_string(Image.open(filename))
os.remove(filename)
print(text)

# show the output images
cv2.imshow("Image", image)
cv2.imshow("Output", gray)
cv2.waitKey(0)

 C:\\Users\\LENOVO\\Desktop\\ocr>python test.py -i image.jpg Traceback (most recent call last): File "test.py", line 44, in <module> text = pytesseract.image_to_string(Image.open(filename)) File "C:\\Python27\\lib\\site-packages\\pytesseract\\pytesseract.py", line 193, in image_to_string return run_and_get_output(image, 'txt', lang, config, nice) File "C:\\Python27\\lib\\site-packages\\pytesseract\\pytesseract.py", line 140, in run_and_get_output run_tesseract(**kwargs) File "C:\\Python27\\lib\\site-packages\\pytesseract\\pytesseract.py", line 111, in run_tesseract proc = subprocess.Popen(command, stderr=subprocess.PIPE) File "C:\\Python27\\lib\\subprocess.py", line 390, in __init__ errread, errwrite) File "C:\\Python27\\lib\\subprocess.py", line 640, in _execute_child startupinfo) WindowsError: [Error 2] The system cannot find the file specified 

This my problem and did lot of search in google but i can't find a proper solution for that. Thank you

Answer 1

Are you sure you installed the Tesseract software? I was getting the exact same error you were, but once I installed Google Tesseract OCR from this link your exact script worked just fine for me and produced an output. I tried for a while to solve the answer just in Python, but I didn't realize that this Python library is really just a wrapper.

You can read the documentation for the Python library, or go to the tesseract GitHub page for more information.

Prerequisites:

• Python-tesseract requires python 2.5+ or python 3.x
• You will need the Python Imaging Library (PIL) (or the Pillow fork). Under Debian/Ubuntu, this is the package python-imaging or python3-imaging.
• Install Google Tesseract OCR https://github.com/tesseract-ocr/tesseract