What to do when Python crawler encounters CAPTCHA
This article introduces the knowledge about "Python crawler encounters Captcha how to solve it." In the actual case operation process, many people will encounter such difficulties. Next, let Xiaobian lead you to learn how to deal with these situations! I hope you can read carefully and learn something!
I. Preface
The registration page of China Zhiwang uses this Captcha. The page is as follows:
II. Preparatory work
1 goal
Taking the Captcha of Zhiwang as an example, OCR (Optical Character Recognition) technology is used to identify the graphic Captcha.
2 Installing tesseract
2.2 Download tesseract-ocr-setup-3.05.01.exe
2.3 installation considerations
Check the Additional language data (download) option to recognize multiple languages.
3 Install tesserocr
pip install tesserocr pillow
After Tesseract-OCR is installed, copy the tesseract-OCR folder from D:\Program Files (x86)\Tesseract-OCR to the following directory
E:\WebSpider\venv\Scripts
4Get Captcha
Save the Captcha graphic locally and name it code.jpg
Three battles.
1 actual combat
1.1 code
import tesserocrfrom PIL import Image image = Image.open('code.jpg')result = tesserocr.image_to_text(image)print(result) image = Image.open('code1.jpg')result = tesserocr.image_to_text(image)print(result) image = Image.open('code2.jpg')result = tesserocr.image_to_text(image)print(result)
1.2 effect
E:\WebSpider\venv\Scripts\python.exe E:/WebSpider/8_1.pyDTKDJR42PFRT
1.3 description
code.jpg is DTKT
code1.jpg is JR42
code2.jpg is PFRT
Comparing the results with actual pictures, the accuracy rate is still relatively high.
2 Combat 2
2.1 code
import tesserocr print(tesserocr.file_to_text('code.jpg'))print(tesserocr.file_to_text('code1.jpg'))print(tesserocr.file_to_text('code2.jpg'))
2.2 effect
E:\WebSpider\venv\Scripts\python.exe E:/WebSpider/8_1.pyDTKD.ll? 42FFKT
2.3 description
code.jpg is DTKT
code1.jpg is JR42
code2.jpg is PFRT
Comparing the results with actual pictures, the accuracy rate is not very high.
3 Combat 3
3.1 code
import tesserocrfrom PIL import Image image = Image.open('code2.jpg') image = image.convert('L')threshold = 127table = []for i in range(256): if i < threshold: table.append(0) else: table.append(1) image = image.point(table, '1')image.show() result = tesserocr.image_to_text(image)print(result)
3.2 effect
E:\WebSpider\venv\Scripts\python.exe E:/WebSpider/8_1.pyPFRT"Python crawler encountered Captcha how to solve" content introduced here, thank you for reading. If you want to know more about industry-related knowledge, you can pay attention to the website. Xiaobian will output more high-quality practical articles for everyone!
